Water Journal March 1986

Overseas with the Australian Water Industry BURMA - CHINA - INDONESIA MALAYSIA - TANZANIA - THAILAND Registered by Australia Post-publication no. VBP 1394

water

ISSN 0310- 0367

Official Journal AUSTRALIAN WATER AND WASTEWATER ASSOCIATION

Vol. 13, No. 1, March 1986 FEDERAL PRESIDENT R. Ll oyd, G.H. & D., GPO Box 668, Brisbane 4001 .

FEDERAL SECRETARY F. J . Carter,

CONTENTS Viewpoint-George Tarjan Austrade .... ... ...... .... ............ . . . .. . .. .. .... ... . .

5

Association News, Views and Comments ........ . ......... ..... . .

6

IA WPRC News ........................ . ..................... .

9

Book Reviews .. . . ............. . ........ .............. ... . ... .

9

Australia's Overseas Aid Program in Water Supply and Sanitation -R. F. Goldfinch ........................ .... ............ .

11

Water Supply for the Singida Region, Tanzania -Snowy Mountains Engineering Corporation

12

Water Engineering in Asia-Problems and Solutions -F. R. Bishop . ..... . ........ .. ... ... ....... . ............ .

16

Overseas Projects Corporation of Victoria . . . .... .. . . ........... . .

21

Index-Water Volume 12, 1985 ........... .. ... ..... .... .. ...... .

21

Combined Sewer Implementation Project-Shanghai -D. C. Hanrahan and M. F. Oddie ..................... .. ... .

24

Box A232 P.O. Sydney Sth., 200 1.

FEDERAL TREASURER J . D. Molloy, Cl- M.M.B.W. 625 Lt. Collins St. , Melbourne, 3000.

BRANCH SECRETARIES Canberra, A.C.T. Dr. L. A. Nagy, 8 Belconnen Way, Page, A.C.T. 2614.

(062 54 1222)

New South Wales C. Davi s, G.H. & D. PIL, P.O. Box 39, Railway Square 2000 (02 690 7070)

Vi c toria J . Park, Water Training Centre, P.O. Box 409, Werribee, 3030. (741 5844)

Queensland D. Mackay, P.O. Box 412, We st End 410 1. (07 44 3766)

South Australia A. Glatz, State Water Labo ratori es, E. & W.S. Private Mail Bag , Salisbury, 5108. (259 0319)

Western Australia Dr B. Kavanagh, Water Au t h. of W.A., PO Box 100, Leederville 6007 (09) 420 2452

Tasmania G. Nolan , G.P.O. Box 78A Hobart , 7001 . (002 28 0234)

Flow Measurement and Analysis in the Chang Jiang .,.

-T. Beer .... ... ................................... . ... . .

29

Wastewater Disposal in Three Regional Cities in Thailand -R. H. Edwards and M. J. Hazell ... . ................... . .. . .

32

Village Water Supplies in Burma -H.F. Eggington . . .. . . ............................... .. . .

39

Historical Malacca-Sewerage and Urban Drainage Strategies for the Future -J. A. Crockett, T. J. Fricke, J. B. Murray and R. H. Smith

44

People and Appointments ..................................... .

48

Conferences-Courses-Events of Interest .................... . .

49

Northern Territory M. Lu kin , P.O. Box 37283 Winnelli e, N.T. 5789.

EDITORIAL & SUBSCRIPTIO.N CORRESPONDENCE G. R. Goffln , 7 Mossman Dr., Eag lemont 3084 03 459 4346

COVER PICTURE The feature papers in this issue cover an extensive geographical area and a wide variety of activities and problems, ranging from the provision of water for the isolated and thirsty communities of Tanzania to the wastes from 'cottage industry' fish processing in Thailand and the pollution problems graphically and descriptively rated by 'stink indices' in Shanghai.

No one cover picture can convey this gamut of activity and the wide gulf existing between the areas and problems in question and those familiar to the majority of readers of this Journal.

Our cover picture provides an aesthetic contrast to some of the teeming problem areas described in the papers whilst still illustrating one facet of a water supply project. The stilt houses are typical of waterfront development in Jayapura in lrian Jaya, one of the case histories in 'Water Engineering . . . ' by F. Bishop .

Cover picture - courtesy Scott and Furphy.

The statements made or opinions expressed in 'Water ' do not necessarily re/feet the views of th e Australian Water and Wastewater Association, its Council or committees.

AUSTRALIA'S OVERSEAS AID PROGRAM IN WATER SUPPLY AND SANITATION R. F. Goldfinch INTRODUCTION Since 1945 many of Australia's neighbours in the Asia/ Pacific Region have begun to develop urbanised economies as large numbers of formerly rual workers move to the cities.

Australian expertise has assisted economic development overseas by contributing to the construction or improvement of urban utilities, including roads, water supply and sanitation. In the process the Australian construction industry has transferred professional and trade skills through both aid programs and directly contracted services.

The ~ustralia~ Develop_ment Assistance Bureau (ADAB) is responsible for 1mplementmg the Australian Government program of assistance to developing countries. The Australian .Department of Housing and Construction (DHC) has assisted ADAB with technical and related aspects of the program.

This paper briefly reviews the funding aspects of Australian Aid and outlines a number of the projects undertaken in Indonesia, certain Pacific Islands and the People Republic of China.

THE FUNDING BASES Aid by Australia is on either a bilateral or co-financed basis. As bila_teral assistance, Australia provides as grant-aid, technical engmeering services, e.g. feasibility studies, design and documentation of projects and also assistance with on-site supervision of co~structi~n : the_ ~~cipient. governments provides counterpart assistance m feasibility studies and onshore materials, e.g. concrete, aggregate.

On a co-financing basis Australia provides as grant-aid the engineering services for feasibility studies; projects may then proceed on the basis of funding from the International Bank for Reconstruction and Development (The World Bank).

INDONESIAN AID PROJECTS Australia's nearest neighbour has a population of 160 million which will probably rise to 220 million in about 20 years. At present, only one quarter of the seven million living in Jakarta have municipal water supply and there are only partial supplies in a few other large cities. There are no sewerage facilities other than old and small systems in Bandung and Yogjakarta. The task confronting the Cipta Karya which (amongst other responsibilities) is the central water supply Authority is daunting . Current expenditure upon water supply and sanitation is some $350 m per annum . In some of these projects ADAB is helping with technical assistance from the DHC. Bandur Lampung is a city of 500 000 in Sumatra. Initially, ADAB an? J?HC; helped _to rehabilitate a prewar water supply system, bnngmg its capacity to 50 L/ s. An engineer from DHC assisted Cipta Carya to construct a further groundwater resource from the Way (River) Linti, of 75 Lis, with chlorination and a 5 ML steel storage. ADAB have now commissioned studies for a 400 L/ s scheme drawing water from the Way Kuripan about 6 km away in the hills, delivering into a treatment plant.

A further proposal for a 1000 Lis scheme from the Way Sahu is more ambitious, and to date, ADAB has not committed itself to funding .

Kota Bumi is a town of 75 000 about 120 km north of Bandung, for which ADAB has provided four deep bores about 7 km from the town, with steel service reservoir, pumps and elevated storage, which supplies water to a reticulation system built by the municipality.

In Cilacap, Java, a population of 160 000 is served by river diversion works and a treatment plant, which was fabricated of

Reg Goldfinch is with the Department of Housing and Construction in Canberra. This article is a precis of a paper presented to the World Plumbing Conference and Exposition in Sydney during September 1985.

st~el components in Australia, and packaged for transport to Cilacap. It was erected with minimum construction work on-site. . To assist t~e Cipta Karya with construction, Australia has provided an Advisory Team consisting of six experts. Based in Jakarta, they travel throughout the whole archipelago, conduct preliminary investigations and submit reports on preferred options, to obtain allocation of funds. They then help to prepare terms of reference for the engagement of consultants for the detaile? designs and contract documents, and eventually help to su~ervise the works, liaising with the local authorities. Projects which may be funded by the World Bank include water supplies for 10 towns, each in excess of 20 000 population in Irian Jaya.

The development of water supplies for rural communities has only been considered recently. The Indonesian Government has also proposed a rural sanitation program with a preliminary target of servicing 40 million people by the end of the decade.

ADAB has engaged an Australian consultant to develop water supply and sanitation for the Island of Lombok which is to involve simple but appropriate technology, such as ;ainwater collection systems, shallow wells with hand pumps, and hand-dug latrines. ¡

PACIFIC ISLANDS In Fiji, ADAB has assisted the government with the construction of a 1500 metre long sewerage tunnel in Suva, and also with a sea outfall at Laucala Bay. Prior to its construction ADAB funded an environmental study. ' Australia has also been involved in augmentation of the Suva water supply. The pumps and treatment plant equipment were supplied from Australia. , T~e Republic of Kiribati (formerly the Gilbert Islands) is apP;O_x1mately 800 km east_ of Nauru. Australia has assisted in prov_idmg sewerage for the islands of Tarawa Atoll, with a population of 21 000. Because the Atoll is only 7 m above sea level, and the only water resources are shallow groundwater lenses in the ~ighly permeable sands, the project demanded some unique solut10ns . Se~water flushing was adopted, with short fairly steep sewers, with a total of 27 inground pumping stations which relay the flow to adjacent sewers and eventually to a small solids removal system, with final discharge over the reef to the ocean.

PEOPLE'S REPUBLIC OF CHINA Australian consultants were engaged by ADAB to perform a feasibility study for sewerage for the huge city of Shanghai. This study is reported in another paper in this issue of 'Water'. This study was funded as Co-Financed Aid, ADAB provided grant-aid to cover the engineering services for the study. Subject to approval, the Chinese Government may then implement the works, funded by loans from the World Bank. The sewerage project alone is estimated to cost over US$1000 million. The studies also extend to traffic control, urban transport and housing.

OPPORTUNITIES FOR AUSTRALIA The business opportunities for Australian Industry in the Asian / Pacific region are substantial. Raw materials and labour capacity are adequate, but there is a lack of skilled professional resources, including managerial capacity to implement projects.

Developing countries in the region are favourably disposed towards Australia, because we have been supportive both in terms of aid and international forums. Our aid programs are commended, not only for the competence of ADA'.8, DHC, consultants and contractors but also for their appreciation of the moral and cultural sensitivities of the local people with whom they are involved.

It is important that future staff and personnel continue to have the same order of competence and attitudes.

To help development and utilise our outstanding advantages re~uires a wholehearted joint effort by Government agencies and by mdustry.

WATER March, 1986

11

Water supply for the Singida Region Tanzania Snowy Mountains Engineering Corporation 1. INTRODUCTION 1.1 Background

A large portion of the 21 000 000 people of Tanzania live in rural areas with only about 2 000 000 living in towns with a population over 100 000. It is one of the poorer countries in the world with a GNP per capita of only US$260 in 1982 (World Bank, 1984) but yet has a very high population growth rate, 3 .40Jo per annum .

At independence in 1961, it was estimated that only 5% of the people in rural areas had access to an adequate water supply.

Since that time a number of European countries have provided aid in the development of water supplies in the different regions of the country. After an approach from the Tanzanian Government through its Ministry of Water Resources and Energy (MAJI), Australia through the Australian Development Assistance Bureau (ADAB) sent an investigating team in 1973 to assess the needs of the Singida Region in central western Tanzania (Figure 1).

Following this the Snowy Mountains Engineering Corporation (SMEC) was commissioned to assist in the development of village water supplies in the Singida Region.

1.2 The Singida Region

The Singida Region covers an area of 49 341 km 2 and had an estimated population of about 700 000 in 1983. The largest town, Singida, had a population of 43 000 but the bulk of the population is rural with some 614 000 persons living in villages, the average population of which is 1800.

The Region occupies the northern part of the central plateau of Tanzania with elevations ranging from 1200 m to 1500 m. About 80% of the area is underlain by igneous rocks, chiefly pre-Cambrian granites, old metamorphics form the basement over the remaining area. Sedimentary deposits of variable depth occur along water courses and in large drainage depressions. Most streams are ephemeral; there are only two permanent water courses. Apart from the southern part of the region which drains into the Indian Ocean, the remainder of the drainage is internal with a number of seasonal swamps and saline lakes.

The climate is characterised by pronounced wet (November to April) and dry (May to October) seasons. Mean annual rainfall varies from about 450 mm in the east to 800 mm in the north-west and south-west. In dry years the rainfall can be as low as 250 mm.

In spite of its near equatorial and inland location, temperatures are relatively mild because of the high elevation; monthly mean daily maximum temperatures at Singida vary from 27.4°C to 32.2°C and 12

WATER March, 1986

The Snowy Mountain Engineering Corporation was established by the Australian Government in 1970 as an independent consulting engineering organisation to retain the engineering skills built up during the 25 years it took to investigate, design, and construct the Snowy Mountains Scheme in south-eastern Australia.

In the 16 years since it was established the Corporation has earned a reputation that places it among the world's leading consulting engineering organisations. Its particular expertise includes the civil, electhe monthly mean daily mm1ma from 13.4°C to 16.9°C. The mean annual pan evaporation at Singida is 2350 mm. Potential evapotranspiration exceeds rainfall in every month of the year. Sunshine duration averages about 7 .5 hours per day.

Mean wind speed varies from 12 km/ h in the dry season to about 6 km/ h in the middle of the wet season; this provides a useful source of energy for pumping water by the means of windmills.

Most of the inhabitants are engaged in subsistence type agriculture and the tending of a livestock population of 1 million cattle, 0.8 million goats, and 0.3 million sheep. The government's Ujamaa policy has resulted in the movement of people from scattered communities to larger more accessible villages with communal land. Residents are organised into units of 10 households, each of which elects a leader. Village councils are responsible for administration but traditional practices still linger. Very few of these villages have reliable water supplies and in many instances the women, who are responsible for this task, spend up to two hours every day to draw and carry water.

K ENY A Lake

11 ir.corifJ

trical, and mechanical engineering aspects of water resources development, power generation and transmission, irrigation and land development, and road engineering and regional development. The Corporation operates on a commercial basis and is set up to provide services to governmental and private organisations, both within Australia and overseas. lt has carried out projects in 43 countries thoughout Asia, Africa, North and South America, and Oceania.

2. THE PROJECT 2.1 Summary

The Project commenced in 1975 and was continued until late 1984 when its essential components were handed over to a non government organisation, the Lutheran World Federation. It took place in four stages: Stage 1, 1975-1976: the provision of two drilling rigs and associated equipment for the construction of deep bores; the drilling of bores; the carrying out of pumping tests and supervision of pump installation; the training of T~nzanian staff.

Stage 2, 1977-1978: the extension of the drilling program to enable more complete training of the Tanzanian drillers (including t1aining in Australia); the provision and mstallation of pumps and windmills; a survey of the surface and groundwater resources of the region .

Stage 3, 1979-1980: the construction and equipping of a workshop for repair and maintenance; the initiation of a program of shallow well construction; the provision of outlets for the bore supplies; the expansion of the hydrologic • and meteorologic data collection program including the setting-up of a water quality laboratory.

Stage 4, 1981-1983: the continuation of previous activities with greater emphasis on the exploitation of shallow groundwater sources and upon training and social aspects; surveys by environmental and community health experts.

The basic components of the project were recognised as : • assisting MAJI in the investigation design, construction, and maintenance of groundwater sources such as boreholes and shallow wells • training staff to provide a pool of skilled persons to facilitate work in the above component so as to assist the MAJI organisation generally.

2.2 Organisation and Staffing

MO ZAMB IQUE

_

Figure 1. Location plan (Singida region shown stippled)

SMEC's organisation for the project was headed by a Project Director who resided in Australia but normally made two visits per year to Tanzania. He was responsible for liaison with ADAB, overall selection and direction of the field

TABLE 1. AUSTRALIAN FIELD PERSONNEL Long Term Staff ing

1975

1976.

1977

/978

1979

1980

1981

3.2 Boreholes 1982

1983

1984

Project Manager Hydrogeologist Drilling Supervisor Mechanical Supervisor Pump Installation Supervisor / Field Supervisor Shallow Well Supervisor Hydrometric Officer Workshop Supervisor

-

Workshop Superintendent/ Training Officer Senior Site Co-ordinator Administrative Officer

-

Rural Development Advisor

-

Training Officer

Short Term Staffing

Time Period 11 /78, 1/79-9/79, 10/79-6/ 80 7/ 78- 11 /78, 7/79-8/79 7/ 82-10/ 82 2/79-5/79 11/83-12/83 l l/83-1 2/83

Hydrogeologist Hydrologist Welding Supervisor Tank Constructor Community Health Expert Environmental Expert

team, the ordering of equipment and supplies, and cost control and reporting. A resident project manager lived in Singida for the duration of the project during which three persons held this position; he was supported by the staff shown in Table 1.

The field team worked in conjunction with the local MAJI organisation headed by the Regional Water Engineer and comprising about 80 support staff including drillers, survey technicians, mechanics, workshop staff, drivers, and clerks. A varying number of labourers were engaged on a casual basis to assist in construction work . A further 30 to 40 Tanzanians were employed directly by the Australian team.

2.3 Living Conditions

Eight houses were provided for the SMEC team on the outskirts of Singida.

Amenities such as a tennis court, video cassette recorder, and ping-pong and pool tables together with special leave breaks were provided to compensate for some of the difficulties of living in Singida which included: • the remoteness of the town; it took two days to drive from Dar-es-Salaam to Singida, a distance of 1060 km, over rough unsealed roads • the absence of other expatriate communities in the area • a severe shortage of consumer goods including every day items such as soap, bread, light globes, etc • the poor communications; telex service was only acquired in the last year of the Project. Prior to that, reliance had to be placed on cables and an uncertain telephone service.

In the early years of the Project, some of these difficulties were overcome by

regular visits to Nairobi for the purchase of spare parts and consumer goods not available in Tanzania but the break-up of the East African community and the subsequent closure of the Tanzania/ Kenya border restricted access later . Hostilities between Tanzania and Uganda also had adverse effects on the Project, making it very difficult to obtain petrol and cement and exacerbating the shortage of consumer goods . Finally the drought conditions that developed in Africa during the later years of the project had an indirect influence by affecting the morale of the local population.

2.4 Logistics

The poor access and communications and lack of spare parts already mentioned, made it necessary to make special arrangements for the supply of such items as tyres for vehicles, parts for pumps etc.

Larger items of equipment purchased in Australia had to be dispatched by sea often leading to delays in excess of three months from the time an item was ordered to its arrival on site. Advance planning was therefore essential.

3. WATER SUPPLY 3.1 Sources of Supply

A complete survey was made of all the villages in the Singida Region to obtain details of the existing sources of supply.

The results from a typical village are included as an appendix. A summary is given in Table 2.

It was estimated that the daily use of water varied from 2.9 L per person to 11.2 L per person with an average of 7 L for villages with improved supplies and 5 L from non-improved supplies.

Initially emphasis was placed on the use of boreholes because of their relatively high yields, their relative security from contamination, and the potential offered for training .

Hydrogeological advice was provided to assist in locating boreholes. Figure 2 shows the results achieved.

Typically the bores were drilled to depths of about 50 m to 100 m. They were equipped with mono pumps (29) and windmills (31). About 25 ferrocement storage tanks with a capacity of 23 000 litres were manufactured locally and erected at a number of bores together with stock watering troughs and reticulation facilities to domestic outlets. Some of these tanks were erected to collect roof runoff at schools and hospitals. The pumps were housed in steel sheds which were prefabricated in Singida.

3.3 Shallow Wells It was soon realised that shallow wells were more appropriate because of their ease of construction and more simple methods of operation involving hand pumps or lifting by buckets or gourds, thus avoiding problems associated with the maintenance of diesel engines and pumps . The wells were lined with concrete rings manufactured on-site and equipped with sanitary seals. A total of 169 wells were constructed (Figure 3). Of the shallow wells about 850Jo were ring wells made of up to six concrete rings 1.5 m in diameter and 1 m 'in length while the balance were tube wells 300 mm in diameter and up to 10 m deep lined with PVC pipe.

TABLE 2. SINGIDA REGION: EXISTING VILLAGE WATER SUPPLIES Type of Supply

Number

Percentage

Shallow wells Boreholes Wells in rivers Springs Lined wells Dams Flowing rivers Swamps

119 71 52 24 22 15 3

39 23 17 8 7 5

4. TRAINING AND SOCIAL ASPECTS 4.1 Training

The training of Tanzanians was always recognised as one of the main objectives of the project, with considerable success being achieved. Training was accomplished by on-the-job instruction, informal lectures, and a number of formal training courses, including: • a 6-week Land Rover maintenance course by a British instructor for 10 mechanics from eight regions • a 3-month course in welding • two courses on pump maintenance and trouble shooting for technicians • a 2-week course on windmill erection, operation, and maintenance for technicians WATER March, 1986

13

and repair; Tanzanian mechanics were carefully instructed before sitting for recognised grade examinations. In 1983 Singida recorded the highest pass rate in Tanzania.

200 -

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al

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4.2 Social Aspects

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0 --~...,.....-----,-------,----------,---~-- ~ -- -,---,-----.--------'-, 1979 1976 1975 1977 1981 1984 1978 1980 198?

1983

Figure 2. Borehole production, 1975-1984.

• two courses for pump attendants in the maintenance of diesel engines and pumps • three drillers were trained in Australia for a period of four months .

The local staff were deeply involved in all phases of the work, often with only general guidance from the the Australian team. Particular emphasis was placed on maintenance. This lead to the establishment of a fully equipped mechanical workshop for the maintenance of pumps, engines, vehicles and windmills. As can be seen from Table 1, a number of Australian specialised workshop staff were attached to the project for long periods.

During Stage 3 it was realised that there was a need to intensify the training of water technicians and to extend the training program to the village level. For this purpose a full time training officer was appointed. He commenced a series of 'Train the Trainer' courses in which Tanzanians were given a five day course in training principles in English.

The more promising of the graduates from these programs then gave similar courses in Kiswahili - some to MAJ! technicians, others to people from the villages.

The result was a surge of interest by the Tanzanians. Each person taking part realised that they could teach others even at a low technical level. The knowledge gained from the Train the Trainer courses was quickly put to good use, particularly

in the field of training villagers in pump repair and maintenance and also in the basic care of wells to cut down disease and pollution.

Shallow well under construction.

Other successes were reported in the training of technicians for windmill and Mono pump erection, maintenance, and repair. Particular attention was paid to diesel enginers and Singida became recognised as a depot of high productivity and expertise. A high standard was set and maintained in vehicle maintenance 60 000

200

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1980

1981

1982

1983

Figure 3. Shallow well production, 1979-1984.

14

WATER March, 1986

(/)

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1984

• consultations with the village council and later meetings with the whole village population to discuss the proposed water supply improvement and the number and location of shallow wells • the involvement of the local people in the construction work, followed by training in maintenance and hygiene.

This was designed to gain full participation by the villagers and thus to promote a sense of local ownership and pride.

Specific attention was directed to the village women who have been traditionally responsible for the collection of water.

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Experience gained during the course of the Project showed that it was imperative to gain the trust of the villagers if the new water supplies were to be accepted and properly used and maintained . This implied consultation with the village leaders at all stages of the process. A Rural Development Adviser was therefore recruited to conduct a sociological program. In co-operation with the local MAJI staff he instituted a program in which the main elements were: • the preparation of large scale maps of each village showing village boundaries , residential and farming areas, existing water sources, other public facilities, and access tracks • the compilation of basic data on human and livestock populations

5. OTHER ASPECTS 5.1 Hydrological Data Collection and Analysis 5.1.1 Data Base A hydraulic data base was established to provide data for current and future investigations. The data collected included: • daily rainfalls from 74 stations • climatological data from four stations (rainfall, air temperature, wet and dry bulb temperature, pan evaporation, wind run, sunshine duration, and radiation)

• daily streamflow records from 18 hydrometric stations together . with discharge measurements, rating curves, location plans, and station details • water level records, surface area and capacity curves, and embankment and spillway details for seven surface storage reservoirs • suspended sediment data from five hydrometric stations and sediment surveys of six reservoirs .

These data were compiled and published (Snowy Mountains Engineering Corporation, 1978).

5.1.2 Analysis

The following analyses were carried out to provide data for design purposes: • rainfall frequency analysis of data from a number of stations for durations ranging from 0.25 hour to 1 year • the extensions of daily stream discharge records from four catchments using the United States National Weather Service Model (the Sacramento Model), the United States Soil Conservation Service procedure, and a modification of the latter • reservoir storage analyses for six storages using a monthly time step to determine the probability of failure for various demands .

As can be seen from Table 3, runoff in this region is a relatively small fraction of the rainfall.

provision of additional water supplies for stock could lead .to a worsening of the existing overgrazing problem that was resulting in serious soil erosion and general catchment degradation . A review by an environmental expert showed that there was no evidence of any increase in livestock numbers as a result of the project and that other environmental impacts were negligible. Certain measures to protect the area in the vicinity of watering points were recommended, however.

5.2.3 Other impacts

Although designed as a rural water supply project, continuing assistance was given to the maintenance of the water supply of Singida town which otherwise would have been faced with acute water shortages. Improved water supplies were also provided for a number of schools and hospitals . Significant benefits arose from the transfer of mechanical knowledge throughout the region and through the availability of spare parts provided by the Project.

TABLE 4. WATER QUALITY OF EXISTING SUPPLIES Property

fluoride

mg/ L

1.5 (22)

1. 4 (19)

iron

mg/ L

0.39 (42)

0.67 (137)

nitrate

5.2.1 Health

Concern had been expressed that the TABLE 3. RAINFALL AND RUNOFF OF SELECTED CATCHMENTS

1971 1972 1973 1974 1975

mean

Msemembo R at Msemembot

rainfall mm

runoff mm

rainfall mm

runoff mm

662 816 489 638 386 598

121 47 99 41 30 68

443 59 1 486 53 1 460 502

64 39 90 85 97 75

Notes: • catchmeni area = 3220 km 1

t catc hment area =

1311 km 1

pH

Max Permissible WHO (a)

Tanzania

1.6 (48)

1.5

8.0

0.62 (209)

0.3

1.0

45

100

900/o of samples © 45 mg/ L

mg/ L (VS/ cm

All sources

l 177 (69)

612 (194)

719 (313)

2300 (c)

7.0 (69)

6.6 (192)

6. 75 (314)

6.5 to 9.2

(a) World Health Organization. 197 1 (b) tent at ive Tan zanian Standard

6.5 to 9.2

(c) ass uming that totar dissolved solids (TDS) = 0.65 EC (d) the numbers in brackets ind icate the number of samples

5.3 Water Testing A water quality laboratory was installed and equipped to carry out simple physical, chemical, and bacteriological tests. A substantial amount of data was collected but difficulties were experienced in maintaining the laboratory equipment and in ensuring a uniform standard in the test results because of inexperienced staff.

Tests were made of the water from a large number of bores, shallow wells, and other sources (surface storages, rivers) during the survey of the existing supplies.

The results are summarised in Table 4.

6. CONCLUSIONS

5.2.2 Catchment Degradation

Ndurumo R at Mgimba*

Wells

units

electrical conductivity

Year

Bores

description

5.2 Environmental Appraisal A public health expert was engaged to carry out a study of health data in the region and to study the impact of water supply on health. It was found that while improved water supplies had the potential for reducing the incidence of water based and water borne diseases, it was important that they be complemented by improved sanitation and hygiene education.

Moreover it was found that in some instances the villagers reverted to traditional sources of supply in the wet season or when a pump broke down. It was also noted that improvement in health was related to the quantity of water used, as well as its quality, and therefore it was important for the source of supply to be as close as possible to the points of use to avoid long trips which restrict the volume carried and amount used .

Placing liners in shallow well.

The Project succeeded in providing improved water supplies to a large number of villages in the Singida Region of Tanzania . It was most successful in training local technical staff.

Among the lessons learnt from the Project were: • the need for consultation with the village people and their involvement in all phases of the work • the need for sanitary improvements and hygiene education to complement the improved water supplies • the desirability of using shallow wells rather than bores for village supplies because of the more simple maintenance and ease of construction.

Completed shallow well with hand pump.

7. ACKNOWLEDGEMENTS SMEC wishes to acknowledge the contrib ution made by the Project Director, Mr. S. K. Stephens and to the successive Project Managers, Mr. E. F. Batt, Mr. A. Duczynski, and Mr. G. T. Roberts as well as to all the other persons who worked on the Project. It is grateful to the Australian Development Assistance Bureau for permission to publish this paper.

For references and appendix sr:e page 37 WATER March, 1986

15

WATER ENGINEERING IN ASIA PROBLEMS AND SOLUTIONS F. R. Bishop INTRODUCTION The United Nations International Drinking Water Supply and Sanitation Decade (1981-1990) is now at its mid-life, still with the target that everyone in the world should have access to a safe supply of drinking water and adequate sanitation by the end of this decade . Various estimates of the cost of providing new water supplys and sanitation systems range from US$20-80 billion/ year of the decade with US$30 billion/year frequently accepted as reasonable. The cost of rehabilitating existing systems is in addition and represents many millions of dollars. This enormous task requires the expenditure of significant resources by the nations of the world and consequently there is a need to focus on the appropriateness of services provided. · Water and sanitation systems in South-East Asia and Oceania must be developed to meet the specific needs of the region. It is not appropriate to adopt western technology without modification to meet local requirements. Far too often in the past, and it is suspected even now, systems were designed to meet the criteria required by and suited to developed western communities with social, economic, financial and environmental requirements differing widely from the Asian community for which the water supply or sanitation system was provided . It is a fundamental requirement that the design be appropriate to the community, and this requires a change in emphasis in planning and design.

This paper examines some of the problems in water supply and salination projects occurring in third world countries, how they differ from those in Australia and the western world and the need for a different approach. The key steps are: • Identifying the need .

• Development of the system.

• Implementation.

• Management of system.

The paper will illustrate some of the principles by actual case studies in Asia and Oceania.

COMMUNITY EDUCATION Consumers in developed countries expect a near ideal, completely safe water, available continuously in virtually unlimited quantity and with a rapid service response from the Water Authority.

In contradiction, the developing countries' consumer requirements for level of service is conditioned by affordability. For many communities receiving their first water supply system there is at the inception, a need for community education by the water authority. The authority must inform consumers of the benfits of clean water on health and amenity, the level of service and its limitations, the advantages of water conservancy and the disadvantage of wastage, the need for cost recovery and the health problems associated with the discharge of excess water to the environment.

SOCIO-CULTURAL ASPECTS Water is not only needed for drinking and cooking, but also for personal hygiene, including bathing, washing and cleaning. Thus it is necessary that water be readily available, whether from house connection, yard connection or standpipe. If public standpipes are few in number and inconveniently located, consumers will utilize more convenient but possibly polluted waters.

Similarly, sanitary disposal of human wastes is essential to eliminate possiblities of people being brought into contact with pathogenic organisms. Sanitation facilities must comply with religious and local customs, otherwise they will not be utilized .

DEVELOPMENT OF WATER SUPPLY SYSTEMS The rate of development of water supplies is limited by two factors - availability of capital funding and the physical resources to implement the works . By far the largest constr.aint to progress 16

WATER March, 1986

Frank R. Bishop, M.Eng., F.I.C.E., F.I.E.Aust. is Managing Director, Scott & Furphy Consulting Group with an extensive professional career in consulting engineering for the water industry.

Responsible for projects in all states of Australia, Indon esia, Malaysia, Papua New Guinea and Vietnam involving water resources, water treatment, hydrology, flood mitigation, sanitary engineering, industrial, so lid and hazardous waste-;......--"...;. management and treatment.

F. R. Bishop Recent and current projects include 10 town water supplies in Irian Jaya, Indonesia, regional water supply for South Kedah, involving two water treatment plants, Malaysia, 250 ML / d water treatment plant at Morgan, South Australia, water supply study for 190 000 future population Port Moresby, PNG and 150 ML / d water treatment plant constructed in three stages. is finance, involving as it does the financial resources of third world countries, those of the donor countries and of the international lending agencies concerned.

With such a large backlog in water supply systems, there is a need to provide infrastructure to as many people as possible. This can only be achieved if a least cost solution is adopted that can be afforded by the community.

The 'least cost' solution ensures that the country's currency and foreign loans are spread further , and hopefully , more equitably in the country. If a water supply is affordable to a community and meets its expectations, it will mean that the community protects the states' capital investment by maintaining the works and meeting the annual operation and maintenance costs and in some instances, possibly depreciation and loan amortization costs.

.,.

LEVELS OF SERVICE The level of service to be approved for the community should be determined on the basis of national and regional requirements.

These will include the percentage of population to be served in the various time phases, the estimated present and future domestic demand, the percentage served by direct house/ yard connection and by public standpipe, the peaking factors, minimum residual pressure in system and last but not least the allowance for unac~ counted water.

Table 1 gives the current level of service for various communities in Indonesia , Malaysia, Papua New Guinea and Burma.

Design target allowances for unaccounted water should be set at 20% which can be achieved by good construction and operation techniques. Augmentation of existing schemes necessitate a leakage survey and remedial action to reduce leakage from the system . Several existing systems investigated by the Scott & Furphy Group have had unaccounted water levels in excess of 40%.

Such large non-revenue water production has a significant effect on the water enterprises' operations and in some cases, reduces the level of service so that consumers lose faith in the system and even refuse to pay water bills.

DATA ANALYSIS Statistical data from the particular third world country's Government should provide some of the demographic and income distribution information necessary to make a judgemental decision on the water supply and sanitation system. It may be necessary to obtain supplementary information from a comprehensive socio-economic survey or a limited data gathering exercise. The socio-economic data will enable informed decisions to be made on the following: • The level of service to be given to the consumers which may determine the affordability of the scheme.

• The ability of the community to pay for the service from their disposable income.

TABLE 1. LEVELS OF SERVICE

Population x 1000 Domestic Demand (L/c/ d) • House or Yard C onnectio n • Public Standpipe

> 1000

210 30

Papua-N e w Guinea

.Malaysia /985t

Indon esian Town Category (June 1984)* 2

3

4

5

2

3

4

500 to /000

100 to 500

20

3

100

10

/0

10

10

10

100

20

500 to 1000

500

JOO

170 30

150 30

90 30

60 30

200

180

170

> 1000

220

• GO! Peli ta IV Policy (June 1984 Revision).

National Water Resources Study Demands given are 1985 values which increase in the future and exclude unaccounted water.

t

5 Rural Area

95

High Covenant

lo w Covenant

Self H elp

Burma /993t Village

Socio-Economic Le vel low

225

185

77

45

Medium

100§ 45

High

120§ 45

130§ 45

t Figures for City of population 500 000. § Demands given are for yard connection, 180 L/h /-d adopted for fully plumbed house.

The success of water and sanitation systems is dependent upon community participation in the planning, development and operation process of the system. This participation enables the community to understand the objectives of the water authority and the reasons behind any system limitation.

APPROPRIATE TECHNOLOGY None of the above requirements imply a diminution in engineering excellence, they do involve the utilization of a design philosophy and creation of standards appropriate to the country and the particular community.

Most of the countries of South-East Asia and Oceania are developing and are in a transitional stage between subsistence agriculture to industrial, mining and major agricultural developments. Thus there is a large untapped labour resource pool available , consequently planners of new schemes must take advantage of this pool of surplus labour and the range of skills available in proposed schemes.

WATER QUALITY AND TREATMENT Most countries in Asia and Oceania have set water quality objectives similar to or the same as the World Health Organization's 'Guidelines for Drinking Water Quality' (1984) or the now superseded 'International Standards for Drinking Water Quality' (1971).

Before treatment processes can be determined, the following steps are necessary: • Determine the range of physical, chemical and bacteriological levels that occur in the water source .

• Establish the treated water objectives.

• Establish the simplest process treatment trains that will meet the objectives with an acceptable statistical risk .

• Plan the treatment process and plant to suit available labour resources and skills, and availability of technology in the country.

A desirable objective is zero coliform organisms and faecal coliform organisms for water entering the distribution system. While it appears simplistic, selection of a good water source requiring minimum treatment achieves two objectives, namely, consistently good water quality and minimal capital and operating costs.

Selection of bacteriologically clean water from groundwater, springs or uninhabited surface catchments offers the best approach as minimal treatment will be necessary. Where surface waters with poor physical characteristics are involved, it is desirable to remove particulate matter to a turbidity level less than I NTU to ensure effective chlorination.

Polluted, turbid, coloured or algae laden water requires comprehensive treatment which implies skillful operation at all times and attendant chemical and operating costs to meet water quality objectives.

The World Bank's policy is to chlorinate all urban water supplies and this policy must be commended , but it must be appreciated that the safety of the water supply is dependent upon effective treatment and disinfection thus reinforcing selection of the best quality water source economically available.

WATER TRANSMISSION The achievement of a safe potable water is paramount for a developing community, however , a vital secondary consideration

The traditional distribution system - Mandalay. is the mode of water source transmission and distribution.

A well designed gravitational supp)y has the merit of providing a continuous, low cost operation and maintenance facility.

Pumped systems necessarily involve energy use and higher O&M costs. They have the disadvantage of the system failing completely if the pumps become inoperative .

If a good quality ground water source is available requiring borehole pumps, an economic judgemental decision must be made.

The disadvantage of pumping is outweighed by little or no treatment of the good quality water.

ENERGY GENERATING Provision of power generating facilities is a major objective for third world countries, with a continuing requirement to meet the domestic, commercial and industrial demand of the country .

Water supply systems requiring power for operation involve the examination of the proximity and reliability of available national power generating and distribution systems. A risk analysis will enable a decision to be made, whether to rely on the local electricity authority in whole or part, or provide complete or partial auxiliary generating equipment.

SANITATION AND DRAINAGE Urban communities in developed countries have usually progressively improved their drainage systems leading to the installation of a piped sewerage system. With a developing country the provision of a safe potable water, with reduction in disease transmission vectors, is a key benefit.

The introduction of a water supply system may result in the discharge of surplus water to the drainage systems carrying polluted water and faecal matter from the urban area. Thus improv~d drain maintenance and limited construction of drainage outlets to waterways will remove polluted water from settled areas and hence the potential for water-borne diseases and for mosquito related diseases such as malaria, dengue fever, filariasis, etc., by the elimatation or reduction of breeding grounds in standing water.

WATER March, 1986

17

A positive garbage management system will enhance community health and reduce flooding problems associated with draips restricted by refuse. Communities in flood prone areas require much more positive flood mitigation methods to protect the housing and reduce pollution from frequent flooding of land in which septic tanks, latrines and pour flush toilets are located .

DESIGN AND CONSTRUCTION The design approach must provide an acceptable level of service, utilize sound engineering principles in appropriate technology and be affordable by the community. A vital factor in the design and subsequent construction of the water supply and sanitation systems is the need for evaluation of the regional and national manufacturing capability and the range of skills available so that the importation of specialist personnel and construction materials can be minimised.

The incorporation of local materials in the system and utilization of local contractors for construction should not only result in lower capital costs overall but also reduce the demand upon foreign exchange.

There may well be merit in minimizing the use of construction ·equipment and resorting to labour intensive methods, eg., using mass concrete and so avoiding the importation of steel reinforcement. On the other hand, importing a rotary rig to drill large diameter deep bores may be warranted rather than rely on local hand operated percussion rigs, which are wasteful in time.

A further benefit is that the water supply and/or sanitation works, if designed appropriately utilizing local materials, will permit a regional pool of skilled and unskilled labour to be drawn upon for the construction works.

MANPOWER PLANNING Rigorous manpower planning is necessary in third world countries for water supply and sanitation projects. For an existing authority, the first step is the preparation of an inventory of existing manpower within that authority covering current staffing and the educational and work experience of the personnel.

Assessment of manpower needs requires identification of skill levels and development potential in that region of the country so that recruitment and training needs can be determined leading to a manpower development plan .

The service objectives and responsiblities of the authority must be established and compared with national and international standards and adjusted to accommodate necessary changes in technology.

In rationalizing the resource needs of the authority, several factors must be resolved: • Can the authority afford the assessed manpower levels?

• Can the manpower needs be satisfied within the authority with training to upgrade existing personnel?

• Can the authority afford the cost of training in-house and/ or at regional training institutes?

• Can specialist labour be recruited from outside the authority or from outside the region without further training?

Manpower planning necessitates a balance between level of service and cost, however, the following concepts must be achieved: • clear definition of tasks • setting performance indicators • achieving accountability of all sub-groups in the authority and that of the authority to its government.

TRAINING The technical success of a water supply system is largely dependent upon the management and operational skills of the authority's staff and labour force. The necessary skills may be developed from 'on the job' training, in-house seminars, regional training institutes, related industries or a combination.

Involvement of authority's staff in the construction of works , and commissioning of equipment plays a useful role for operating personnel.

The provision of comprehensive, clear Operations and Maintenance Manuals, written in the language of the country is an essential requirement so that the Water Authority's staff can be fully informed on operational and maintenance procedures .

Manuals need to be broken down into segments relating to specific sections of the system, with the"text writt~n in a technical18

WATER March, 1986

Irian Jaya -

a water-front tribute to Chic Sale.

ly correct fashion, but in a form that is understandable to plant operators and attendants, clerical and administrative staff of differing educational levels. Diagrams, sketches and stylized drawings are essential to present a clear picture, rather than a conglomeration of manufacturers' general arrangement drawings which are frequently confusing to non-engineers and semi-skilled technicians.

MANAGEMENT The key functions performed by a water authority are a mixture of administrative, financial and technical functions. Achievement of the financial and service objectives of the authority require effective management.

The management function includes the development of an efficient operational structure, planning manpower and training needs and the conduct of an effective community education programme with consumer response . In all this, the management of people is the prime consideration. ' Effective management will ensure task definition avoiding duplication of function, the development of individual responsibility and accountability and achievement of the objectives of the authority. +

REVENUE The income of water authorities derives from a number of sources, typically from a rating system based on property valuations with a charge for excess water over the basic water allowance covered under the rate. This with some variation is the approach generally utilized in Australia. In contrast, in South-East Asian countries water is sold by measure either on a flat or a sliding scale. The importance of accurate metering, regular water reading, effective billing and collection from consumers is paramount. Any reduction in unaccounted water becomes a significant savings in cost.

The fundamental message is that effective management of a water enterprise must cover administration, finance and strategic planning as well as the technical operations and maintenance aspects, and all these aspects necessitate training .

CASE STUDIES The following Case Studies illustrate some of the key factors in water supply and sanitation projects: Case 1 -

Denpasar Water Supply, Bali, Indonesia

The water supply for Denpaser, the Provincial Capital of Bali, was undertaken by the Australian Government in association with the Government of Indonesia . Four sources of supply were investigated for an estimated daily demand of 48 ML/ d (year 1990).

Caldera lakes and major springs some 30-60 km from Denpasar were discarded on the grounds of inadequate yield or excessive capital costs. The surface source, Kali Ajung, was found to be highly polluted, partially regulated for major irrigation subaks (co-operatives) and a stream flow analysis indicated an inadequate yield to meet the town water supply and irrigation demand .

Geophysical surveys were completed to the North and West of

Denpasar. The Northern survey, some 10 km from Denpasar near the villages of Tega! and Luk Luk, showed most promise and was confirmed by limited test drilling. Production drilling of 11 bores with depths in the range 125 to 215 m was completed by a specialist Australian drilling contractor with a top casing of 323 mm FRP and 200 mm bottom casing with multiple stainless steel screens to intercept the varous confined aquifers.

The safe yield of the bores range from 30 to 70 Lis with a wellfield output of 446 L/ s. The water quality from the well field has good bacteriological and physical characteristics with moderately high hardness .

The raw water is chlorinated and supplied direct to consumers, except that the water company ('PDAM' Denpasar) installed a 40 Lis Sodium Zeolite Degasser Packaged Plant to treat 50% of the water supplied to the hotels in Sanur. Submersible pumpsets lift the water through a 600 mm dia. rising main to a balance tank where it is chlorinated before gravitating to a 10 ML roofed storage tank at Belusung from whence the water gravitates to Denpasar, Sanur and Benoa.

In 1985 two further bores were commissioned and put into operation deliveri ng 100 Lis. Three of the initial well field pumping stations were equipped with auxiliary diesel generating . facilities as were the latter two .

The well field rising main, trunk main, distribution and reticulation mains are asbestos cement pressure pipes in sizes from 100 to 600 mm . Minor reticulation mains and house services were constructed in rigid PVC in sizes from 12 to 75 mm dia.

All house and yard services and public standpipes are metered as are the well field pumping stations and trunk mains.

The merit of the water supply system could be summarized as follows: • Raw water of good bacteriological quality obviating the need for treatment.

• Apart from the bore hole pumping, the system is a gravity supply.

• The security of well field pumping (and water supply) is achieved with auxiliary generating facilities.

• Key technical staff of the water company were involved in construction and commissioning of equipment. The current Director of PDAM , previously Head of Operations, worked for the consultant from the start of the project.

The combination of good construction methods and hydraulic testing of all water mains, coupled with metering of trunk mains and adoption of an effective consumer metering, meter reading and billing system has resulted in an acceptable percentage of unaccounted for water. An evaluation by Australian Aid Advisors to Cipta Karya in 1983 gave an unaccounted water measurement of 27%.

The current concern is that consumption is of the order of 224 L/ h/ d and is well in excess of the original design allowance of 150 L/h/ d for inner areas and 105 L/ h/ d for outer areas and of the 1985 Cipta Karya allowances (Table 1) . Consumer education and revision of tariffs is expected to rectify the over-consumption.

Case 2 - Central and South Kedah Regional Water Supply, Malaysia

Kumarasivam, Tan & Ariffin Sdn. Bhd . in 1982 in association with Camp Scott Furphy Pty . Ltd. completed a Facility Study and Master Plan for a regional water supply for Central Southern Kedah, Malaysia, for the Jabatan Kerja Raja (PWD) Government of Malaysia.

The 1985 population in the Study Area was estimated at 366 000 persons rising to 612 000 in the year 2010.

There is an acute shortage of potable water in the region with only 51 ML/d available in 1982.

The water demand to serve urban centres, villages and industrial estates was estimated at 105 .4 ML/ d for the year 1985 and 243 ML/d for the year 2000.

There are very limited groundwater resources in the state of Kedah, and surface water resources have been heavily utilized for irrigation. The main source of water is the Sungai Muda which is regulated and supplies the MADA Irrigation Scheme, and bulk supply for P enang State. The other source is the Sungai Kulim, which is currently unregulated but supplies the Penang State 48 ML/d Water Treatment Plant at Toh Allang together with Irrigation Demand which is equivalent to 30% of the Sungai Kulim mean annual flow. Three schemes were investigated in detail and the adopted scheme provided for four treatment plants (Table 2).

TABLE 2. PROPOSED WATER TREhMENT PLANTS Source

Location of WT Plant

Stage

Capacity ML/d

Construction & Commissioning Period

Sg. Kulim

Kg. Wang Pinang

1 2

27 13 68 68 7 7 9 9

1984/ 85

Sg. Muda

(Kulim WTP) Pinang Tunggal (Sg . Petani WTP) Kuala Ketil

Sg . Muda

Jeniang

Sg. Muda

2 2 1 2

1985/ 86

three utilizing the Sungai Muda and one the Sungai Kulim; with pumping, service storages, regional distribution system, and an offstream regulating storage for the Sungai Kulim catchment at a cost of M$187 million (1982 costs).

The adopted scheme had the lowest water tariff (with an internal rate of return of 8%), could be implemented progressively and was more flexible than the other options considered.

Because of the dire shortage of water in the Kulim area, the first stage of the Kulim WTP (27 ML/d) was implemented and went into production in 1985. The Pinang Tunggal (Sg. Petani) WTP is in course of construction in 1986 and will serve the major urban and industrial developments in and around the major town of Sg. Petani.

The waters from the Sg. Muda and Sg. Kulim are both slightly acid waters of low alkalinity with turbidity ranging from 5 to 100 NTU and colour ranging from 5 to 70 CU. Iron levels are consistently above 0.3 mg/ L but manganese levels are low. Faecal pollution to a moderate level occurs throughout the year, which is borne out by morbidity and mortality statistics from the state of Kedah.

The river waters require coagulation, sedimentation and rapid sand filtration to remove particulate matter before disinfection by chlorination. This was confirmed by jar testing and examination of plant operation and operating logs of the Toh Allang and Pinang Tunggal Water Treatment Plants.

The treated water quality objectives are: 5 NTU Turbidty Colour 5 CU Coliforms 1 Org/ 100 ML The 27 ML/d Kulim Water Treatment Plant and the 68 ML/d Sg. Petani Water Treatment Plant were designed to meet these objectives and comply with the Jabatan Kerja Raja (PWD) water treatment design criteria.

The plants were designed to suit Malaysian conditions, minimize the use of mechanical equipment, enable competent operation and maintenance with regional semi-skilled and unskilled labour and limiting imported specialist engineers or technicians as far as possible .

The treatment processes utilized are shown in Table 3.

The merit of the water treatment design is: • Continuity and effectiveness of treatment is achieved by simplicity in design with no unnecessarily complex mechanical/electrical equipment.

• Conservative rating of the process ensures achievement of the water quality objectives under a wide variety of raw water conditions .

• Effective plant operation is achieved with semi-skilled personnel.

• It permits utilization of local unskilled labour for desludging sedimentation units with consequent elimination of some mechanical equipment.

Case 3 -

Irian Jaya Water Supply, Indonesia

The water supply for the 10 major urban centres in the Province of Irian Jaya is an Australian Aid (ADAB) project cofinanced with the IBRD (World Bank). The project towns are the Provincial capital Jayapura and the abutting centre of Abepura, the towns of Sorong, Manokwari, Biak, Merauke, Nabire, Fak Fak, Serui, Wamena and Timika. The current population of the towns is 338 800 and the design population (2010) is 963 000 of whom 765 000 will be served.

Investigations in Irian Jaya were carried out in late 1983/ 84 and again in 1985 to establish the extent and condition of the existing WATER March, 1986

19

,___

13 .00

X

9 .QQm

- 30 .00 --- - - - - - - - -

I

r--- B a ffl es

i-------

-

-'

L

op e nin g

r

, - - B at tl es at 536 mm Crs .

at 430 mm Cr s.

ater

-

-,

I

.

f-------.,,__

)

9 .QQm

Op eni ng 450 S Qr

-u

--------i

~

.

'"'---. r100 mm Di a . Op enin gs _J at 300 x 300 mm Cr s.

X

b

l.

I

Manu a l S ludge Dr a w Off

Figure 1 shows the general layout of the Water Treatment Plant at Sg. Petani.

water systems. A hydrological and hydrogeological programme was set up and implemented together with installation of supplementary gauging stations and limited geophysical surveys.

Engineering surveys were completed to confirm critical information for design, and flow measurements, leakage surveys and water quality measurements were completed in 1985. A socioeconomic study involving an extensive 10 town census, with analysis of data was undertaken by Scott & Furphy Engineers in association with economists Dwyer Leslie & Partners. Currently in 1986 master plans and preliminary designs are being completed.

The preferred option for each community is the least cost solution that can be afforded by the particular community.

A key factor in the project has been the transfer of technology.

The Director of Water Supply, Cipta Karya appointed the Indonesian Consultants PT Unisystems Utama and PT Arkonin to work with Scott & Furphy Engineers, the Principal Consultant.

The Terms of Reference provide for the Principal Consultant to be responsible, to undertake major aspects of the project, but to advise and assist the local Consultants in preparation of Master

Plans for the towns. The Principal Consultant has had eight long term staff in Indonesia and 13 sho rt term engineers while the Indonesian Consultants have had 30 engineers and draftsmen involved in the proj ect.

A further feature is the responsibility of the Principal Consultant in conjunction with the Director of Water Supply, Cipta Karya, to develop an institutional system suitable for the lrian Jaya region, together with an appropriate training system. The World Bank, Cipta Karya, and ADAB, recognize that the success (socially and financially) of the water supply schemes depend upon provision of an adequate continuous supply of potable water and this achievement must again depend upon the effectiveness of the institutional system and personnel in the system.

TABLE 3. TREATMENT PROCESSES Process

Type

Rating

Detention/ Use

Remarks

Waterfall aeration

0.03 m'/m' / hr

Oxidatio n

Kulim only

Aluminium Sulpha te

15-60 mg/ L

H yd rau lic mixing in hydraulic jump

Vel. Gradient G 1000 sec-•

H ydraulic (around the end baffle)

Tapered flocculatio n G values from 80 to 40 sec-'

Detention 15 minutes minimum

Horizontal flow tank s intermediate dividing floor (Lovo ty pe)

Upper surface loading 2 m/ hr

Detentio n 2 hrs. with ma nual sludge removal

Filtration

Sand media

4.87 m/ hr wi th 25% overload)

Water a nd air scour.

Constant rate filtration

Kulim Stage I

Disinfection

Chlorination

1-10 mg/ L

30 min.

Residual 0. 3 mgL

pH Correction

Volumetric dry feeders

25 mg/ L max .

Lime

Fuorida tion

Loss of weight dry feeders

I mg/ L sodium silico fluorid e

Aeration

or iron,

degassing Coagulant Coagulation

Flocculatio n

Sedimentation

20

WATER March, 1986

Liquid

Job instruction in Indonesia.

Case 4 -

City of Mandalay Sanitation

The Socialist Republic of Burma appointed a consortium of Australian Consultants led by Coffey & Partners to the ADB financed Mandalay Water Supply and Sanitation Project. Scott & Furphy Engineers were responsible for certain sections of the water supply design and the sanitation study, The provision of safe potable water in adequate quantities to the City of Mandalay will provide a substantial improvement to public health . However, this is only the first step and Scott & Furphy Engineers has undertaken a detailed sanitary study, which considered the other essential aspects for the enhancement of public health in sanitary collection, drainage improvement, improved solid waste management, rodent/ insect control and community education .

The study examined existing sanitation practices, the cultural basis for them and the relationship to public health. Preliminary proposals ranged from septic tanks to communal toilets and included VIP latrines, vault toilets and PF toilets. Overriding social or technical factors changed the final recommendation by deleting communal and vault toilets and adding conveptional

sewerage for areas with population densities greater than 30 000 . persons/ km 2 .

The means of conveying flood waters and sanitation flows in Mandalay is by canals and the master plan recommended improvements to ensure reduced standing water for mosquito breeding, removal of faecal matter quickly, and the prevention of flooding and associated wide spread distribution of faecal matter.

It was recommended that industrial wastes be treated at source by conventional lagoons. Similar treatment of sanitary flows at a central facility prior to disposal to a major surface water source was also considered necessary.

The sanitation study also recommended improved solid waste management practices to reduce rodents , and the implementation of a rodent/insect reduction programme.

The success of the proposed measures to improve public health, will rely heavily on the community education programme for school children and the community as a whole.

The merit of the sanitation plan is that community health will improve and be affordable. No one can dispute that a conventional piped sewerage system is best, but frequently it is beyond the financial capability of the average family unit from its disposable income.

* * * * * OVERSEAS PROJECTS CORPORATION OF VICTORIA Established by the Victorian Government in March 1985, the Corporation's aim is to facilitate participation in overseas development schemes by both the private and Government sectors.

With its Board of Directors , drawn from private and Government sources and responsible to the Minister for Industry, Technology and Resources, the OPCV is an important part of the State Government's Economic Strategy and it has the capacity to assemble the total resource requirements of large and complex projects. The Board includes amongst its members experts in project financing, education and training, agriculture and water resources , export of manufactures, overseas project management and consultancy.

The Corporation places great emphasis upon fields where Victorians have demonstrated expertise and skill - agriculture, water supply, irrigation, sewerage, health , energy and education.

In addition to its existing overseas marketing expertise, the corporation is recruiting specialists in certain fields to liase with

* INDEX

domestic consultants and contractors for overseas projects. A recent appointment, as Project Manager, is Mr Robin Povey, previously with the Department of Water Resources' Water Training Centre at Werribee and well known in the A WWA. In its short period of operation , projects completed by the corporation include: • training courses for water and sewerage personnel from the Pacific Islands and S.E. Asia • provision of a trickle irrigation expert for Pakistan • a joint venture in a commercial salt resistant plant nursery in Bahrain • provision of design expertise for an animal diagnostic laboratory in India • a review of Mandalay Dairy Project in Burma • the drafting of minerals legislation for the kingdom of Tonga.

The Charter of the OPCV recognises the possibility of action as a prime contractor or as part of a joint venture team and of assisting in designing a funding package and negotiating finances with local and overseas agencies .

* * * * WATER VOL. 12, 1985 ,.

No . I - MARCH Beaches . . . ... ... . .. . .. . .. ... . . . J. D. Court and D. D. Low Water Treatment in Queensland Power Stations . .. ............ ..... . . . . . . . . ... . R. Roberts Cowra Water Treatment Plant, Uprating Water Quality Impact of a Augmentation ..... . . . ...... .. .. . .. .. . . .... S. M. H. Jones Fire in a Chemical and Pesticide Advanced Sewage Treatment for Western Warehouse .. . . ....... R. A. Craswell, R. Sadler, G . R. Shaw Sydney . . . .. . ... . . .. . .... . . . . ... . ... ..... .. . .. B. Walters Water Index 1983 and 1984 Computer Controlled Diversion Scheme Water Quality Enhancement in the Georges River Catchment, Sydney .... ....... . . . . P. J. Fish~r Burnett River .. .. . ... . . . ... . . . . . . ... .. . . ... . . M. C. Miller The Mandalay Water Supply Project .. .. ... .. . .. R. M. Lehman No. 4 - DECEMBER No. 2 - JUNE Biological Nutrient Removal in South Africa Dr. Michael Flynn Award D. W. Osborne and Paper - 1985 . .... .... ... . ... . ... . .... . . .. H. A. Nicholls Ammonia Control and Effluent Polishing

by Parrots Feather in an Aquatic Treatment System .. P . M. Nuttal, R. I. Kerr and J. D. Scholes Convention '85 Report and Manufacturer' s Exhibition . ... . ..... .. . ... . . .... .. . Editor Geelong Ocean Outfall Project D. M. McLeary Upgrading of Existing Wastewater Disposal Facilities at Black Rock ... . .. . ... . and D.S. Barkley Water Treatment - Changing Perspectives ..... . .. . ... .. N . D. Johnstone and R. F . Goode No. 3 -

SEPTEMBER

Strategic Plan for A WW A - A Perception . . .. .. .. ... .......... ..... .... . . . . F. R. Bishop Report - Seminar on Desalination, Adelaide .. . .............. . ... . . . . . ... . . . . . ... . N. Palmer Development of Beach Pollution Index for Sydney Coastal N. R. Achuthan, J . D . Brown,

The Role of Science in Water Management Ed. E . H . Sanders A Basis for Action or an Afterthought.

A Joint Workshop Report .. . . . . ..... ..... and W. H. Maher Gungahlin Surface Water Management ...... . . ... . .. J. F. Neal Conference Reports: -National Strategies for Managing Hazardous Wastes . .. Editor -Hydrology and Water Resources Symposium, 1985 . ... .. . .... . .. .. . . .... ... . .. . . . . ..... .. . . H. Bandier -International Association for Hydraulic Research ... . . . ... . . . . . .... . .... . . ...... ...... H. Bandier Professional Training in Water W. Maher, D. Cullen Science . . ............. . . . . .. ..... .. . .. . .... and R. Morris Control of Sewage Treatment Pond Odour using Actizyme . ... . . . .... . . . .. .. . .. .... . . . .. R. J . Gilbert RIVER SANDS PTY . LTD. High Qua lity

FILTER MEDIA Manufacturers at REDLAND BAY ROAD CARBROOK, QUEENSLAND 4130 Te lephone: (07) 209 8344 WATER March, 1986

21

Combined Sewer l~plementation Project Shanghai D. C. Hanrahan and M. F. Oddie ABSTRACT A major strategy study of the liquid waste management problems of the city of Shanghai is described. A wide range of options were considered before a strategy involving a major interceptor and disposal to the Chang Jian estuary was recommended and approved . The elements of the first stage implementation project are outlined.

BACKGROUND In May 1983 agreement was reached between the Australian Government, the Chinese Government and the World Bank to carry out the Shanghai Urban Studies as a co-financed project, under which the Australian Government wou ld provide technical assistance to the Shanghai Municipal Government to analyse a number of urban infrastructure problems, to develop appropriate strategies and to identify development projects which could be considered for World Bank funding.

Four sectors were selected for study: housing, liquid waste, traffic management and public transport. In August 1983 the Australian Development Assistance Bureau (ADAB) appointed a consortium of consultants led by Pak-Poy & Kneebone and Maunsell & Partners to provide technical advice and assistance to the Chinese project teams set up by the Shanghai Government. Within that consortium Binnie & Partners were responsible for the liquid waste sector. This paper deals only with the liquid waste management problems and the so lutions developed for them.

The initial concept was that the studies would involve a series of short visits by a team of specialists who, on each visit, would review existing data, reports, proposals etc., discuss these in depth with their counterparts and agree upon work programmes of data gathering and option development to be carried out by the Chinese team in preparation for the next specialist visit. The Chinese team would be responsible for the overall direction of the study together with its day to day management. In practice, however, because of the wide differences in approach between the Australian and Chinese teams and the lack of familiarity of the Shanghai officials with western analytic techniques, it was found far more productive to rearrange the schedule of visits to allow for an almost continual presence of a core team of Australian advisors with a wide range of general skills, with key specialists visiting at appropriate times. The Australian consultant assumed the lead role in direction and management of the study. Once this working pattern had been established a very friendly and cooperative working relationship was developed between both parties .

24

WATER March, 1986

Michael Oddie, M.A ., F.I.E.Aust., F.I. C.E. is Managing Director of Binnie & Partners Ply. Ltd., having been a director since 1977. He has a degree from Cambridge and worked on major dams in Pakistan, Iraq and Africa as well as other water resources and waste disposal projects before coming to Australia in 1970.

He has been responsible Jor the Shanghai liquid waste project since the Inception Visit in 1983 and has also visited northern China as part of an ADAB mission to identify further water resources projects.

David Hanrahan, M.Sc., M.I.E.Aust., is Project Engineer with Binnie & Partners Pty. Ltd. He is a civil engineer with experience in the U.K., from M.I. T. He has

D. C. Hanrahan

M. F. Oddie

been the with Binnies since 1980 and has worked on several major strategy studies.

He was deputy to the Project Director for the Shanghai study.

~ •o

10

;o

.

l't lLOi.,in~ E5

J I/INGSU PROVINCE

E/IS T CII IN/1 SEA

H/I NGZHOU B/1 Y

Figure 1. Shanghai area

EXISTING SITUATION The essence of the liquid waste problem was the very poor quality of the Huangpu River which flows through the centre of Shanghai (see Figure I). The city of Shanghai is built on the southern shore of the Chang Jiang (Yangtze) estuary, with the administrative boundaries of the Municipality encompassing about 6000 sq. km of very flat delta country including several major inhabited islands in the middle of the estuary. The Chang Jiang dominates the water resources of the

region. It is one of the world's largest rivers in terms of both flow and sediment discharge, and its tidal range of about 4 m is the dominant force for the hydraulics of the Shanghai region. The maximum salinity recorded at the confluence of the Huangpu is in the order of IOOJo seawater.

The Huangpu is the largest in a complex network of streams and canals which provide transport, water supply and waste disposal for the inhabitants of Shanghai and neighbouring regions With an estimated half million kilometres of

waterway within Shanghai' s boundaries, and with tidal influences from the Chang Jiang extending at least to Dianshan Lake, 100 km up the Huangpu from its confluence with the estuary, it is extremely difficult to analyse the hydraulics of the area. Net flows in the Huangpu at the city are about l0OJo of the tidal flo ws, and net upstream flows in the river have been recorded in the summer when irrigation demands in the highly fertile delta soils are at their greatest. The extent to which the Huangpu is fed from a separate catchment or from upstream reaches of the Chiang Jiang is conjectural.

The population of the central urban area, known as 'City Proper', is about six million within an area of 141 sq. km. This City Proper was the designated area for the urban studies. A furth er fi ve million people live in the Municipality which , though largely rural , includes several significant urban areas . Municipal water supply to the City Proper is mainl y taken from river intakes on the Huangpu within the urban area . The water is filtered and chlorinated before being pumped directly into supply. There is no significant storage in the system. Many industries also pump from the river or from groundwater.

Human domestic waste disposal is centred on the nightsoil system with the wastes being transported by barge to the countryside for use as fertilizer. In redevelopments within the city, such as major new blocks of housing, septic tank systems are used and new developments on the urban fringes are fully sewered.

Within the existing city area the main drainage system is a combined sewer which receives all industrial and domestic wastes apart from the nightsoil and septic tank effluent , as well as storm water.

(There are a few small areas of separate sewers within the city but they are not significant at a strategy level). The combined sewer has developed as the creeks and drains in the urban area have been piped and covered and consequently it is flat and interconnected . Subsidence of the city centre due to over-pumping of groundwater has necessitated the construction of flood walls along the main rivers and sluice gates on the remaining urban creeks. Subsidence has also required that a large number of stormwater pumping stations be provided to lift high flows from the sewer into the creeks .

Figure 2 shows the extent of the existing combined sewer. There are two existing 'interceptors' that carry a portion of the dry weather flow away fro m the City Proper and discharge it on the shores of the estuary (with poor environmental consequences adjacent to the outlets).

The role of the waterways as transport arteries is also very signficant. The creeks and canals in the city are jammed with thousands of work barges and are lined by hundreds of relatively small cramped factories and workshops. The waterways are the thoroughfares, drains, working environment and even homes to millions of Shanghainese. This situation adds another level of complexity and uncertainty to any attempt to improve and maintain the creeks .

- ---- - -

PROPOSED INTERCEPTOR

- --

EXIST!NGSlWERS

•

PU11PUIGSTATIONS

Figure 2. Existing combined sewerage system

THE POLLUTION PROBLEM The water quality problem is evidenced by the poor quality measured at water supply intakes along the urban reaches of the Huangpu. High values have been recorded for significant pollutants such as phenol and mercury but the major measure of gross river pollution is the graphically named 'index of stink ', an empirical formula based on measured dissolved oxygen and ammonia values.

The number of occurances of the ' black stink' , when this index rises above a threshold value of five, has increased steadily from about 20 incidents in 1963 to over 150 in recent years. This deterioration mirrors the rapid industrial and urban growth in Shanghai over the past decades and has no w reached the stage where, in the summer months, the Huangpu River almo st reaches a n anaero bic state and is in a grey and malodorous condition, while many of the smaller creeks are clearly in the grip of the black stink .

Public health figures show that infant mortality is low and stable at about 14 per 1000 births, and the incidence of infectious disease is also satisfactorily low .

These good fi gures are generally attributable to heavy chlorination and the standard practice of boiling all water before consumption . However the city does have reportedly high rates of the cancers commonly associated with industrial pollution, such as stomach and liver cancers. Consequently the Shanghai Government has made the decision to construct a major new water supply intake 40 km upstr~am of the city from where water will be piped to the existing treatment plants. Relocation of the intake was therefore taken as a presumption by the liquid waste management stud y. This decision removes one of the prime reasons for committing resources to improving river water qualit y.

THE SIZE OF THE PROBLEM .

The average dry weather flow generated

Typical Shanghai waterway.

WATER March, 1986

25

within the study area is estimated at 3 .4 million tonnes per day (using the local measure - equivalent to 3400 MLD or about 40 cumecs). At present all this flow ends up in the local waterways or on the shores of the estuary either by direct discharge or via the combined sewer system and the Huangpu River. Studies by the local Environmental Protection Bureau (EPB) showed that about 2.4 million tonnes of the total came from industrial sources and identified 800 plants as the major contributors of wastewater.

Industrial output is programmed to increase dramatically over the coming decades.

Average net flows in the Huangpu River are estimated at around 400 cumecs, with net flows dropping markedly in the drier periods.

The objectives of the study were set in terms of goals for improvement of river water quality and deadlines for the achievement of specific numerical standards, the most basic being a dissolved oxygen (DO) level of 4 mg/ L in the city waterways. In order to examine the behaviour of the river and to assess the impact of possible strategies a numerical DO model of the Huangpu was developed. This model is based on the AUTOQAL model and is described elsewhere(l).

The model was calibrated and verified by data obtained from two major water quality surveys carried out by the Chinese in the summers of 1981 and 1983. Increases in wastewater loads up to a design year of 1990 were estimated and modelling of those loads showed that failure to take action would result in continued deterioration and anaerobic conditions in the Huangpu. The modelled results are shown in Figure 3. Examination of the loads and their distribution also showed that the major tributary creeks would continue to be in even worse condition than the main river.

DEVELOPMENT OF STRATEGY The initial steps in strategy developments were to examine the extent to which the loads could be reduced and to determine the assimilative capacity of the river so that the major civil works req1,1ired could be minimised. It was found, however that it would be necessary to remove all identifiable loads from the waterways in order to come close to the designated standards and that, even with relaxed standards, almost total diversion of waste loads would be required. At the same time, detailed investigation of the types and sizes of wastewater sources showed that total loads would continue to grow, despite proposed improved management practices, becaus~ of the high growth rate of industry and the upgrading of domestic facilities. Eventually a peak would be reached after which replacement of ,., older inefficient plants or migration of industry to areas outside City Proper would result in a gradual decline in total loads. Consequently, although a wastewater control programme became a major element of the overall strategy, it became clear that 26

WATER March, 1986

.,,

treatmenf would not quite achieve the required water quality levels. The problem in this case was the high 7 INI SHIOO I ! nitrogenous . biochemical oxygen demand (NBOD) in the treated effluent retained in I • >I the poorly flushed river long I >::; I >enough to cause significant I I ' reduction in DO levels .

I I l<JIIIHG SIJZMOO CREEK CHANGQ[AO I r••f However a major improvez _I_ __ _I_ )LI_ j_ T "'~ ment in river quality would _r be achieved and further I I I I .,. ..i CITY PROPER : 0 reductions in effluent levels "':l I I i I ! 1I 'r··' could always be made (at 0 J I s igni fic a n t cost) . The "''011 I ''II ir"' technology for secondary I I I treatment is well established __ ,i 2 L .. although choice of the best I I ! :I process train would require I !

I \ considerable investigation, so there were no doubts as to the I : I.... . .:. .. :....!_,!

I ' : overall feasibility of this L .. _ I strategy . ., 12 14 • • 20 I • ' The massive size of the IIIVEII JUNCTION HUMIEII facilities required was a major drawback to any seconNOTE : SA.SEO ON lOt LOW FLOW ---- -.ru~IT'I' CI-J[CTtV[ (1. , , - 90~ ElCEEDENCE) dary treatment option . It proCASE P-EOICT£D 1990 DES IGN CASC ved virtually impossible to -- IA.SE ( flt()ll 19111 ANO 1983 SI.M'f'CYS ) - ··-· \fJTH NO AC TIOfll locate the required 50-70 ha close to the city and the river, Figure 3. Modelled river quality either as one site or as a number of smaller significant construction works would also ones. The sites finally identified wete so be required. far out as to negate, to a large extent, the Examination of the existing system advantage of being able to use the river to showed that the combined sewer network accept the final discharge. Nevertheless it should be retained, despite some signifiwas possible to develop technically feasicant disadvantages, because of the imble options which though failing to totally mense difficulty and cost of providing a satisfy water quality ,criteria, would be new collection system. The major implicajudged environmentally acceptable. tion of this decision was that some A wide range of potential outfall opflushing of sewers to the waterways would tions were considered in the process of always occur after heavy rainfall; debate identifying th~se which were genuinely as to the acceptable level of such feasible. A shoreline discharge would reoverflows continued for a long time. quire full secondary treatment (as was Following from the decision to retain clear from study of the effects of the exthe combined system it became clear that isting two interceptor discharges) and was the starting point for new works would be therefore considered as a treatment option some form of interception of the sewer rather than as an outfall. An outfall to discharges at or near the existing stormHangzhou Bay in the south of the water pumping stations. The major Municipality see med a reasonable strategic issue then became the appossibility until investigation showed that• propriate location for final 'disposal' of the bay is shallow, brackish and poorly these wastes (meaning their return to the flushed . Discharge to the deeper water environment) and the requisite level of outside the advancing delta front is not treatment required. feasible since the distance to the 10 m conA wide range of possible approaches tour was over 30 km offshore and over 80 were considered. Some of these were km from the city. quickly ruled out on a variety of grounds: Studies of available charts and disposal by recharge of groundwater was historical records of the estuary showed , not acceptable because of the shallowness however , that while the advancing delta of the aquifers and their use as water front was shallow and highly mobile, the sources; land irrigation was not acceptable main river channels behind the bar were because of the industrial content of the efdeep (over 20 m in places), fast flowing fluents and because of the meterological and becoming more stable. Examination conditions; lagoons as a form of treatof these areas identified a relatively stable ment were impractical because of the huge site close to the city and an outfall option land requirements which could not be was developed for this area based on a satisfied within an economic distance tunnel through the silts under the river from the sources. The viable strategic opand diffuser risers jacked up from within tions fell into two groups. The first involvthe tunnel. This technique had already ed treatment to secondary level and been used on several similar far smaller discharge back to the river system. The seoutfalls and intakes in the Chang Jiang cond group comprised deepwater and it was believed that it could be scaled discharge to the Chang Jiang estuary (or up to the size required for this project. A further offsh_ore) with a minimum level of wide range of other construction technitreatment . ques were examined but all face problems Analysis of a range of treatment opwith the fast flowin g, silt-laden river and tion~ showed that a secondary level of the very heavy shipping traffic into the ,0

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port of Shanghai. It was concluded that it would be technically feasible to construct a tunnel outfall, but a surety of continued operation in the face of major siltation or scour was identified as a major technical i5sue to be resolved in the future design studies.

The level of treatment required for a discharge to the estuary was very carefully investigated with comparisons being made of existing water quality, effluent concentrations (both at present and after imposition of industry controls) and required environmental standards. It was established that the net water flow in the estuary provided adequate assimilative capacity for the achievement of water quality goals considered on an estuary wide basis.

Thereafter, for the satisfaction of local goals, it was demonstrated that screening of the effluent would be sufficient, provided the diffuser achieved about 100 in. itial dilutions. The provision of primary treatment was examined but the improvements to pollutants of concern did not justify the very large cost and the accompanying sludge problems.

A number of outfall options were prepared based on different outfall locations and carriers routes and these options together with the treatment options and a mixed option were subjected to a full evaluation and comparison . The principal conclusion of the evaluation was that the outfall options were about half the cost of the treatment options, that the environmental effects on the estuary were balanced by the higher level of river quality achieved and that the feasibility of the outfall was not in doubt although there were some difficult technical issues to be addressed.

An outfall strategy was therefore recommended by the stud y team, based on the preferred outfall location , and this recommendation was accepted by the Shanghai Government , ADAB and the World Bank. Though the need for action was never seriously queried, it is of interest that it proved impossible to present convincing economic justification for the investment.

PREFERRED STRATEGY The preferred overall strategy for management of liquid wastes in the City Proper area of Shanghai was established under three headings: physical, financial and institutional.

Heavy pollution, junction of Suzhou Creek with Huangpu River.

• appropriate action to be taken to remedy the unsatisfactory discharges from the existing two interceptors • continuation of the planned secondary treatment for new urban areas.

• establishment of the operating authority as an autonomous financial entity, with responsibility for fund raising and revenue collection at the appropriate level to enable it to plan, construct, operate and maintain sanitation services.

Financial Components

• adoption of an objective of full userpays for industry, and of a (subsidised) level of charges for domestic users

-Institutional Components

• establishment of a legislative framework that determines the , appropriate powers CHANG J IMIG ESTUARY OUTFALL

- - - CATCHMENT BOUNDARY

- - - PROPOSED INTERCEPTORS ~"-.

"-. ~ CATCHMENTS INTERCEPTED

EXISTING WESTERN INTERCEPTOR

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Physical Components

• at-source reduction of industrial loads by management or on-site treatment to achieve minimum standards. These standards were to be generally based on the criteria of no damage to the sewerage system with provision for requiring some industries to reduce total loads of specific pollutants to a level consistent with the assimilative capacity of the estuary • construction of an interceptor system to divert the discharges from the existing combined sewer system • preliminary treatment by fine screening of the intercepted wastes and discharges to the Chang Jiang estuary through a diffuser system

1/

EXISTING SOUTHERN INTERCEPTOR

010203040 KILOMETRES

Figure 4. Stage 1 Project -

initial layout WATER March, 1986 27

and responsibilities for implimenting the physical plan, for operating and maintaining the existing and proposed facilities and for management of the assets; • development of ordinances for better control of liquid waste discharges by industry and for strengthened licencing and monitoring powers; • establishment of a body responsible for coordinating or controlling the various and competing uses of the water resources of the Huangpu basin.

PUMP STATION + 10

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km.

ST AGE 1 PROJECT It was clear from the initial costings that the scale of the physical works required was too large to be undertaken as a single project. In addition, because the interceptor/ outfall system is essentially a linear one it is necessary to complete a very large proportion of the total works before it is possible to begin to use the system. Consequently, the immediate task following the acceptance of the physical strategy was to develop a first stage project which would be within the financial resources likely to be available and which would provide early relief to the overloaded river system.

A range of possible staged or discrete options for providing an acceptable outfall system were examined and the Stage 1 Project as eventually adopted for strategic planning purposes was as shown in Figure 4. It consisted in essence of a tunnelled interceptor picking up discharges along Suzhou Creek, the most heavily polluted part of the river system, a large pumping station on the estuary side of the Huangpu River which lifted flows into a screening and grit removal plant and then a culvert to the preferred site on the estuary where the effluent would be pumped through a tunnelled diffusion system about one kilometre offshore in about 20 m depth.

Initial estimates of the order of cost of the project were US$300 m, although it was noted that with the difficulties of costing a project of this size and the special problems of estimating prices in a non-market and rapidly changing economy the final cost was likely to be significantly higher. The design and construction period was estimated to be a minimum of seven years.

The identification of this Stage 1 Project marked the end of the Strategy Study phase. The final report noted that the design was at the outline level only and identified a wide range of technical issues to be addressed in the next phase.

The Liquid Waste Management Strategy Study report was reviewed at several draft stages by ADAB and the World Bank and by the completion of the final draft it was agreed that development of the scheme should continue directly into the next phase - the preparation of a preliminary design for funding appraisal by the World Bank - so as to maintain the momentum that had been generated by the Shanghainese team and their advisers. This decision resulted in an extension of the liquid waste consultancy to allow for continuing advice and for the establishment of a permanent core team of consultants based in Shanghai.

28

WATER March, 1986

TREAT MENT OUT FALL PU MP /AT STATION~

HUANG PU + 10

1--- - -R-IV _E_ R=:\

- 10

GRAVITY CULVERT

SIPHON

0 1 - - km.

mAOO

Figure 5. Typical long section

PRELIMINARY DESIGN The major technical issues to be addressed in the preparation of the preliminary design are confirmation of the location and design of the diffuser and determination of the best configuration of the main interceptor, in particular the location, type and size of the pumping facilities required . In addition, a full set of outline designs for all aspects of the project has to be prepared. This work is at present underway, with an anticipated appraisal of the project early in 1986.

Further studies, including physical modelling of diffuser systems and estuary dye tests to determine diffusion values have shown that adequate dilutions can be achieved at the original preferred site while examination of estuary processes and historical records have confirmed that this is a relatively stable section of the estuary. Nevertheless, the design of the diffusers will have to be capable of coping with changes of the river bed level in the range of + 10 m (siltation) to - 25 m (scour), in extreme circumstances. A number of riser configurations are being examined and a full scale prototype is to be constructed.

The selected outfall location allows a range of alternatives for the rest of the interceptor, and a wide range of possible configurations were examined. Constraints included the need to tunnel under the dense inner city, very poor soil conditions at about 40 m depth which put a practical limit on pumping station options, difficulty in routing culverts through intensely farmed areas, the necessity of crossing the Huangpu River, hydraulic implications arising from the interception of all stormwater flows up to a certain level, and of course costs - which were somewhat rubbery, at times. Most of the candidate routes follow more or less that shown in Figure 4 but combine tunnel and culvert, and tunnel sections.

One typical route is shown in Figure 5 with only the first 12 km in tunnel, at which point a major pumping station lifts flows of up to 42 cumecs through a head

of 35 m into a large culvert. A siphon is used to cross under the river to the site of the treatment plant from where another length of culvert (making a total of about 15 km) leads to the coast. Further pumping is then required to provide the necessary head to drive the outfall diffusers. A major issue is the location of the terminal pumping station, with current thoughts favouring a site close to the treatment works.

Work continues ' to finalise the preliminary design and to prepare all the other material on financial , legal, and organisational aspects required for full appraisal of th! project. If funding for the project is approved in 1986, then the target date for commissioning the project will be 1992 - a formidable task.

ACKNOWLEDGEMENTS The work described here was funded by the Australian Development Assistance Bureau. More than 20 consultants from at' least nine firms participated in the Liquid Waste Management Study at one time or another. The members of the study team worked exceedingly well together under often very trying conditions which contributed much to the success of the project.

•

FLOW MEASUREMENT AND ANALYSIS IN THE CHANG JIANG Torn Beer ABSTRACT Current measurements in large estuaries subject to intense maritime traffic and strong tidal currents pose special problems in relation to the design of moorings.

When the data are to be used in subsequent design investigations then it is important that data analysis and storage be in a simple to use computer compatible form. In the case of the Yangtze River the Chang Jiang, current meters were moored from a large light ship normally used as a navigation buoy. Data analysis of the retrieved current meter data tapes .was done with a pre-programmed Cromemco C-10 computer.

The collected current meter data was related to river flow by comparing the current meter results with those obtained during an intensive survey. Other uses of the data included its decomposition into harmonic constituents for subsequent prediction of the tidal currents; and its use in converting tracer concentration versus time curves into concentration versus distance curves thus enabling calculation of estuarine dispersion coefficients.

INTRODUCTION During 1984 and 1985 , the Australian Government, through the Australian Development Assistance Bureau, funded the Shanghai Urban Studies Proj ect. The overall project covered four major aspects: Housing, Transport, Traffic Management and Liquid Wastes, and involved a team of Australian experts offering advice to the Shanghai Environmental Protection Bureau on the best practicable means of overcoming problems in these areas.

An overview of the Liquid Waste Project is provided in a companion feature in this issue of Water, which outlines the requisite work to arrive at the decision to discharge liquid waste to the Chang Jiang (Yangtze River). Once this decision had been made, and accepted by their Chinese counterparts, then it was necessary to organize studies of the likely environmental impact of liquid wastes discharged from selected diffuser configurations. The companion article deals with the wider issues, this article deals with the background investigations on the estuarine physical characteristics required to determine an engineering design that would provide appropriate environmental safeguards. A simultaneous benthic invertibrate reconnaissance provided background information on the organisms subject to impact.

number four. For the last 100 km of its flow, the river passes through a flat delta consisting of lakes, tributaries and canals connected with the main channel. At about 50 kilometres from the mouth the river begins to branch into a series of channels and passages separated by large cultivated islands and many shifting sandbanks .(Figure 1). Maximum river depths in this area are over 30 m but depths near the mouth are less than 10 m due to the formation of bars from the river's vast sediment load estimated to be 550 Tg (550 Mt) per annum (Holeman, 1968).

The Chang Jiang is a major transportation artery which plays a chief role in the development of Chinese commerce. It provides access for large ships to inland ports over a thousand kilometres from the river mouth. The Huangp u River, on which Shanghai is situated flows into the Chang Jiang at Wusong Kou.

The estuary of the Chang Jiang .has a large tidal range, with Table 1 listing the tidal constituents at the Wusong Kou signal station. The tides are semi-diurnal, though tidal predictions need to include both diurnal and shallow water constituents. The large tidal range induces fast currents in the river.

120°E EAST CHINA SEA

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DAZ HI

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The Chang Jiang

Chang Jiang, meaning Long or Great River, is one of the largest rivers of the world. It has a catchment area of 1.92 million square kilometres, and its mean flow, listed by Holeman ( 1968) as 28 500 cubic metres per second, ranks it as

Tom Beer graduated B.Sc. from Sydney University and gained his Ph.D. from the University of Western Ontario. After some years on research with the ANU Centre for Resources and the Environment he joined Natural Systems Research Pty . Ltd. and is Associate Director of that organisation. He wa responsible for the work described in this paper, carried out for Binnie and Partners and is presently advising the Mekong Secretariat of the United Nations on a program of salinity intrusion studies in the Mekong Delta.

X .,.-- -

Figure 1. Locality map -

PROPOSED OIFF USER SITE SHANGHAI MUNICIPALITY BOUNDARY

Shanghai Municipality and the Chang Jiang.

WATER March, 1986 29

TABLE 1: TIDAL LEVELS, WUSONG KOU (PORT 7284) Highest Astronomical Tide Mean High Water Spring Mean High Water Neap Mean Sea Level Mean Low Water Neap Mean Low Water Spring Lowest Astronomical Tide

4.3 m 3.5 m 2.5 m 2.0m 1.4m I.Om 0.1 m

Source: Admiralty Tide Tables , Volume 3 (1985) .

The Chang Jiang Delta

The delta of the Chang Jiang estuary is geomorphologically active and continues to develop a system of seaward branching channels. At present, three levels of diversion are clear: North and South Branches, North and South Channels and North and South passages. In addition there appears to be a further subdivision occurring in the South Passage, consistent with the ·continued bifurcation of the southern element at each level.

Chinese records of the development of the estuary extend back thousands of years (Chen Ji-Yu et al., 1982) . Two thousand years ago the estuary was funnel shaped and tidal bores travelled far upstream . At this time the site of presentday Shanghai W:'lS under water and it was only in the 10th Century AD that it emerged as a coastal fishing village. This active geomorphology of the estuary results in constantly changing bathymetry. Thus an adequate flow investigation had to combine current meter investigations with accurate hydrographic surveying.

DATA REQUIREMENTS Estuarine variables to be monitored to provide data on the likely fate and environmental implications of the discharge of liquid wastes from an outfall are: • Vertical density profiles • Current • Lateral dispersion.

The density of water is determined by temperature and salinity and, in the case of the Chang Jiang River, by its sediment load. The vertical profile of density determines the buoyant rise and entrainment, of any wastes discharged from a subsurface outfall or diffuser. A data set covering at least one year should be obtained from any potential site, so that Seasonal variations are adequately considered.

Wastes, once discharged through an initial diffuser, will attain neutral buoyancy and will then continue to be diluted by lateral turbulent dispersion from fluctuations in current speed and direction. In addition, bacterial levels will continue to decrease, especially in salt water, as a result of microbial decay.

Current-Salinity-Temperature

Aanderaa RCM4S current meters were chosen for the collection of the requisite current, salinity and temperature data.

These are cost-effective, proven and reliable instruments which are the workhorses of oceanographic investigations.

The current meter internally records information at a predetermined sampling rate on current speed, direction, and 30

WATER March, 1986

temperature with salinity and depth (inferred from pressure) as options. The recording system ·consists of quarter-inch reel-to-reel magnetic tape with the information coded into ten-bit binary words.

The magnetic tape can store 10 000 samples on 600 feet of magnetic tape on three inch reels. For a typical long-term estuarine sampling program which records information every ten minutes this offers a theoretical autonomy of 69 days. In practice, monthly servicing of the meters was carried out because the occasional battery will not last two months and the rotor and vane need to be checked for fouling.

The choice of current meter mooring in a high energy estuarine environment involves evaluation of costs, manpower and equipment availability, and relevant design limitations. The drag force on an immersed object varies as the square of the water speed and the mooring was designed for a speed of 2.5 mi s. The final choice for the Chang Jiang consisted of a moored navigation lightship 22.1 m long, held by twin anchors on a vertical line from the ship. Three current meters were suspended, one near the surface, one at mid-depth and one near the bottom. Current meters will not record horizontal speed accurately if their tilt is too great and the Aanderaa, which uses a compass card, cannot operate correctly if the vertical tilt exceeds 12 degrees. The current meters were accordingly ballasted with 200 kg of lead to overcome drag-induced tilt; a boom with a block and tackle arrangement was used for monthly retrieval.

The current meter array was positioned over the proposed outfall site. This is near the location of the Gao Qiao hydrographic station where meteorological information is collected and regular water samples are taken for analysis of the suspended sediment load.

TABLE 2: M~NU OF DATA ANALYSIS FUNCTIONS 'Shanghai Liquid Waste Disposal Menu of Functions': 'Estuarine Hydrodynamics Program Data Analysis' I. Help 2. Read in current meter data from Aanderaa tape reader 3. Generate a work disk of current meter data 4. Display current meter data listing on the computer screen 5. Print current meter data 6. Plot current meter data as time series or progressive vector plots 7. Plot vertical profile data 8. General purpose plotting program 9. Display more of the menu 10. Copy to or from an IBM-PC disk (PC-DOS 1.00 and I. 10 only) 11 . List filenames of files on the currently selected disk drive 12. Copy a disk file 13 . Copy a whole disk for backup on a blank disk 14. Check disk 15 . Compare the disk in drive A with the disk in dri ve B 16. C-10 Self-test 17. Initialise a new disk (to be run before reading in a new tape) 18. Display Main Menu

direction, salinity, temperature, density and depth. The C-10 has an RS232 output port and it is possible to simultaneously connect a printer and plotter to this single port by using a parallel connection for the printer and a serial connection for the plotter. Separate pin,s are used for both connections so that both sets of wires can run from the same plug. Typical graphical output from the plotter is depicted in Figure 2.

DATA ANALYSIS To obtain information from the collected estuarine data, a dedicated data base management scheme was established using an NSR/ Tain Electronics tape reader unit and a Cromemco C-10 personal computer. The C-10 is menu-driven and the menu choicees are displayed in Table 2.

The C- 10 consists of a Z80A microprocessor, 64K bytes of RAM , a keyboard, terminal and dual double sided double density 5.25 inch floppy disk drives each capable of storing 390 K of data . It has inbuilt communication capability through a UART comprising a Synertek 6551 chip, so that no hardware modification to the C-10 is necessary to interface the tape reading unit to the computer. The information from the current meter tape is read in to the C-10 and stored, in binary form, on floppy disk. Because of the relatively long disk access time a handshaking protocol between computer and tape reader was necessary, so as to buffer the input whilst a disk write was in progress.

The disk of raw binary data is transformed to engineering units via menu choice number 3, which produces an ASCII file of date, time, current speed,

Gao Qiao hydrographic station.

Single site current meter results on their own are insufficient to provide suitable flow data and need to be supplemented with information on the vertical and transverse variations of the current and on the estuarine cross-sectional bathymetry.

During an intensive survey, the Shanghai Navigation Bureau collected hydro-

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graphic data from four stations on the Gao Qiao cross-section during March 1985. The Navigation Bureau estimated the mean estuary velocity from twenty readings through the estuary crosssection; five at each station . These data were compared to the simultaneous data from the lightship mooring and it was found that the bottom current meter, at 16 m depth, recorded a velocity (V) very close in numerical magnitude to the estimated mean estuary velocity. A linear regression gave: V = 0.97 V + 1.99 (cm/ s) with a coefficient of determination of 0.97.

The Navigation Bureau also related flows and velocities during their intensive survey and obtained: Q = 649.8V where Q is the flow in cubic metres per second (cumecs) and the mean velocity is in cm/s.

LATERAL DISPERSION The Nanjing Hydraulic Research Institute has developed a mathematical model to study the expected fate of liquid wastes released from the proposed diffuser. The Institute utilised longitudinal dispersion coefficients between 10 m2 /s to 30 m 2 / s, with transverse dispersion coefficients an order of magnitude lower. It was decided to confirm these values with a field experiment and the selected technique was the slug injection of the fluorometric tracer Rhodamine WT. Fluorometric tracing is cheaper than radiometric tracing, and the results can be obtained more quickly. There are a large number of possible fluorescent dyes that can be used but Rhodamine WT has the least decay in sunlight and the least adsorption into sediment (Smart & Laidlaw, 1977).

Preliminary analysis of the current

meter results indicated slack water at the outfall site 2 hours after high and low tide at Wusong Kou . For detailed experimental design the collected current meter data was decomposed into its harmonic constituents and these constituents were used to prepare tidal speed prediction tables.

One hundred litres of Rhodamine WT were released at 12.30 pm on 23 July 1985 and water samples collected from five locations for up to 36 hours. The tracer was released on an ebb tide, two hours before slack so as to ensure that the main portion of the tracer cloud would travel upstream and not be lost in the East China Sea. Detectability of the Rhodamine was affected by the large sediment load of the river . The natural silt load in the absence of Rhodamine produced a background reading on the fluorometer equivalent to a Rhodamine reading of 0.4 micrograms per litre, it was found that concentrations above 1 microgram per litre were necessary for a suitable signal-to-noise ratio. The absorption due to this high silt load was greater than that found in laboratory experiments (Smart & Laidlaw, 1977).

Because of financial constraints it was not possible to organise the experiment in accordance with the recommendations of the original experimental design. A pilot test, designed to provide operational testing of all the equipment and experience for the personnel was not conducted. Most importantly aerial observation of the tracer cloud was prohibitively expensive and the vessels used for sampling were unable to locate the tracer after the first turn of tide. Aerial observation combined with ship to air communication would have overcome this problem.

The time series of tracer concentration obtained from the fixed observation sites, combined with the simultaneous current meter data was used to infer the spatial variance of the dye cloud as a function of

time and hence arrive at a figure of 38.8 m 2 / s for the longitudinal dispersion coefficient. Because the vessels lost the tracer and were unable to conduct transverse transverses through the tracer cloud a direct measurement of the transverse dispersion coefficient could not be made .

Indirect estimates based on mass continuity yielded a transverse coefficient of approximately 0.6 m 2 / s, through this value is subject to ccfnsiderable uncertainty.

CONCLUSION The measurement of flow, in a fast moving tidal estuary, involves difficulties additional to those found in gauging unidirectional rivers. The technology is amenable to transfer to less developed nations and the appropriate skills can be ob- • tained by hands-on experience.

Personal computers have the capability, and when properly programmed, the userfriendliness to be a cheap and effective method of data storage, retrieval and analysis . A suitable computer interface is required before the full potential of current metering can be utilised. Once the computer system is in place, and the current meters have been deployed, then the objective of the study determines the use to which the data are put. The Chang Jiang data were used in application as diverse as diffuser design, flow rating, tidal speed prediction, and in the design and analysis of dispersion experiments.

ACKNOWLEDGEMENTS The author wishes to acknowledge the contribution of the staff of the Shanghai Environmentai Protection Bureau who arranged the logistics and provided personn~l for the current meter and dye tracing investigations.

CONTINUED ON PAGE 37 WATER March, 1986 31

WASTEWATER DISPOSAL IN THREE REGIONAL CITIES IN THAILAND R. H. Edwards and M. J. Hazell ABSTRACT In recognition of the importance of regional urban centres in national development planning, the Royal Thai Government is implementing the Regional Cities Development Project. The Project is concerned to improve both public infrastructure and municipal administrative systems in an initial programme of five main regional cities.

Sinclair Knight & Partners in association with Thai consultants has carried out feasibility studies and completed detail 'design of infrastructure improvement for five cities which will be constructed 1986-91 and financed by a combination of World Bank loan and Central and Local governme.n t funds. The wastewater components of the Regional Cities Project included provision of a management philosophy, data collection and interpretation, establishment of design criteria and detail design for municipal wastewater collection and disposal in two of the cities, Khan Kaen and Chiang Mai and for wastewater generated at a proposed new fishing port and industrial development in a third city, Songkhla.

1. INTRODUCTION This paper deals with the alleviation of wastewater problems in three of Thailand's regional cities - Khan Kaen, Chiang Mai and Songkhla. At Khan Kaen and Chiang Mai the works were directed to wastewater collection and disposal improvements throughout the city areas whereas at Songhkhla, the work was limited to upgrading facilities in the fishing port/industrial area of the city.

More specifically, the works comprise: • Khan Kaen: 6.9 km of sewers to intercept dry weather sewage flows from street drainage upstream of the stormwater main drains and a treatment works to treat these flows prior to discharge into receiving waters.

• Chiang Mai: 5.8 km of interceptor sewers to divert wastewater flows to enter the drainage system below the city with a view to being fully treated at a future time.

• Songkhla: separation from the stormwater system of waste flows from fish handling, processing and marketing at the fishing port and treatment in a wastewater treatment plant prior to discharge to Songkhla lake.

These various wastewater management and disposal works form part of the broader Regional Cities Development Project which aims to improve the urban infrastructure and living standards in five such cities of Thailand by the construction of new works and upgrading of existing works. Infrastructure improvements were considered necessary because of the cities' importance as regional centres and the objectives of regional development in the National plan.

32

WATER March, 1986

Robert H. Edwards is a Director of consulting engineers Sinclair Knight & Partners and is responsible for the firm's water supply and wastewater treatment practice. He is a civil engineer with over 20 years experience in Australia, United States of America, Papua New Guinea, Burma and Thailand in investigation, design, contract documentation and construction supervision of water supply, sewerage and waste disposal projects including pumping stations, pipelines, treatment works, reservoirs, reticulation and sanitary landfills. Bob made a major contribution to the Regional Cities Development Project in Thailand by overseeing the public health aspects of the feasibility study.

Martin J. Hazell is a Civil Engineer with 13 years experience in wastewater treatment and disposal. Originally with the Water Authorities in the UK as a senior design engineer, he worked for four years The responsiblity for the design of the complete works was shared by the consultant team, and Royal Thai Government Agencies (Public Works Department, National Housing Authority and the Municipalities). The consultant team comprised Sinclair Knight & Partners as lead firm, which provided senior staff to manage the project and to lead the specialist groups carrying out each section of the work, and three Thai firms which provided professional, technical and administrative staff. These firms were Team Consulting Engineers Co. Ltd., Asian Engineering Consultants Corp. Ltd. and Sumet Jumsai Associates Co. Ltd. This association and interaction between expatriate and local consultants, and government personnel was instrumental in fulfilling another government objective of maximising technology transfer.

2. THE REGIONAL CITIES DEVELOPMENT PROJECT The Regional Cities Development Project as a whole included a broad range of project components. A feasibility study was completed in 1982 and detail design commenced in 1983. The estimated value of works for which bid documents have been prepared by the consultant team totals US$35 million. A further US$9 million of works has been designed by the Government Agencies . Proposed works, other than for wastewater management and disposal, include: • Main drainage works totalling 10.6 km of major channels.

• Street drain improvements totalling 40 km of new and upgraded drains .

• Solid waste disposal facilities for three cities.

• Two bridges in Chiang Mai. • A riverside area redevelopment in Chiang Mai. • A fishing port and an associated 22 ha

R. Edwards

M. Hazell

in Papua New Guinea planning and designing main sewage wastewater treatment and waste disposal facilities. He is currently with co nsultin g engin eers Sinclair Knight & Partners as a senior engineer. Martin has spent the last year working in Bangkok, Thailand on The Regional Cities Development Project as Group Leader for the design of public health aspects. development for fishing related industries.

The feasibility study was funded by the United Nations Development Program (UNDP), while the detail design and some section of ongoing project and construction supervision are funded by The A ustra lian Development Assistance Bureau (ADAB) under its co-financing agreement with the World Bank.

The construction of works will be jointly financed by a US$27. 5 million World Bank loan, Central Government funds and Municipal finance. Construction will be carried out through 46 contracts during 1986-91 of which two are open to international bidding.

The project is the first in Thailand to: • make available international funding for regional city development.

• make an internationally funded project to be jointly managed with the Thai Department of Local Administration, the Public Works Department and the Cities all taking part.

• use joint funding from the World Bank, the Central Government and the cities.

• involve modern methods of solid liquid waste disposal and to provide a planned approach to infrastructure problems in the regional cities .

• develop new administrative procedures to cope with the project's implementation for budgeting, city revenue components, approvals, procurement of goods and service and supervision of construction.

3. KHON KAEN AND CHIANG MAI 3.1 Existing Domestic Wastewater Disposal The majority of domestic installations in the cities of Khon Kaen and Chiang Mai are pour-flush squat plate privies connecting to a porous cesspool. A minority have two cesspools in series. Kitchen and laundry wastes have discharged directly to soakways or to storm drains. A trend, not

yet widespread, is for 10 L flush toilets and septic tanks to be installed in the higher value homes. Institutions ¡ and larger factories generally have treatment plants although many of these are often inoperative.

In many domestic installations absorption of cesspool effluent does not occur due to a combination of inadequate size of soakage areas and impervious gro und.

The result is the discharge of septic effluent into street stormwater open drains.

These are of very flat grades and often partly blocked with garbage resulting in anaerobic stagnant pools and eventual pollutio n of receiving waterways.

Many households have illegally piped their effluent to the street drains and waterways. This effluent is not subject to treatment and in each city the quality of receiving waters falls well below the minimum standard of downstream use. ¡ Cesspools and septic tanks are emptied and desludged by private contractors using a vacuum tanker. The cost is high and hence carried out infrequently. The private contractor will pay a commission to the Municipal Council. Much indiscriminate dumping of tanker contents is practised adding to pollution of drains and waterways.

In Khon Kaen city a 1981 survey by the Department of Town & Country Planning indicated that 980Jo of the households interviewed had on-site cesspool/soakway facilities. Cistern-flush toilet-septic tank systems were being installed in the city, particularly at hotels and new houses . The sur vey also showed 16 0Jo of the households had cesspools overflowing to the stormwater drains and 380Jo reported that their toilet facilities blocked up in the wet season .

Other statistics indicate that the number of installations emptied by tanker has been falling year by year due to an increase in illegal connections to street drains.

Corresponding data for Chiang Mai were that 940Jo of households had on site cesspool/soakage, with 120Jo of these overflowing to storm drains and 220Jo having blockages in the wet season.

NONG LEONG PLUAY

2km SCALE MUN ICIPAL BOUNDARY -++-+-4-

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Figure 1. Khon Kaen 3.3 Condition of Receiving Waters

The lake Bung Thung Sand in Khon Kaen receives directly the flow from the main drain. It has an area of approximately 2.8 km2, is shallow and has a moderately high salt content. The lake has been subjected to waste discharges from the city for more than 20 years. Sedimentation of organic matter and insoluble settleable solids have substantially reduced its effective area and volume. The lake is in a eutrophic state, floating weed is prolific and anaerobic decomposition is oc-

3.2 Existing Stormwater Drainage System

The principal features of the stormwater drainage systems of both cities are the main drains which flow around the central part of the city and convey all storm and wastewater runoff below the city. In Khon Kaen the main drain, the Rong Muang, flows into a lake, the Bung Thung Sang. Overflow from the lake occurs in the wetter part of the year to a natural adjacent reservoir, the Nong Loeng Pluay. (See Figure 1).

In Chiang Mai the main drain , Mae Kha, has two tributaries, the Mae Tha Chiang and Lam Khee Wai. It eventually joins the larger Ping River 4.5 km south of the city . (See Figure 2) The central parts of the city are furnished with drains along both sides of the main street which discharge to the main drain along its course .

In the dry season the natural flow in the main drain ceases . At this time it conveys only sullage and other types of wastewater from the cities.

Wastewater catchment area.

curring at the lake bottom. BODs figures in the lake as high as 140 mg/ L were ' measured .

The lake is an important fisheries resource and approximately 700 fishermen and fish farm enterprises earn a living from the lake . -rhe lake water is also used for an adjacent fisheries station which grows fingerlings which are used to stock nat ural watercourses, reservoirs and private fishponds in the region. It has been reported that there has been a reduction in fish size and weight.

Within Chiang Mai the Mae Kha main

2 km

SCALE

AIRPORT

LEGEND NEW M U NICIPAL BOUNDARY OVERALL CATC HMENT BOUNDARY FOR M AE PING

Figure 2. Chiang Mai -

Wastewater catchment area .

WATER March, 1986

33

An inner city drain, Chiang Mai.

drain has a very flat gradient resulti ng in very low flow velocities even in the rainy season . Large parts of it are overgrown with aquatic weeds and the bottom is covered with black organic sludge from the inflow over many years of untreated sewage . The Mae Kha has become a pollut ed and unpleasant waterway degrading commercial and res id ential areas and adversely affecting tourism, one of the city's main industries.

3.4 Downstream Water Uses

The Nong Leong Pluay, an elongated lake downstream of the Bung Thung Sang in Khon Kaen, discharges into a river, the Lam Phra Khu. The lake is used for fi sheries and subsistence agriculture. It is stocked yearly from the fisheries station .

The Bung Thung Sang is the most significant contributor to the Nong Loeng Pluay of dead algae, residual organic matter and nutrients. These result in dense hyacinth growth which inhibits fish cultivation and the anaerobic decomposition of dead hyacinths and roots creates septic conditions. The waters of the downstream river , the Lam Phra Khu, are used for community water supply, and subsistence agriculture.

In Chiang Mai , the Mae Kha has been utilised as a maj or source of water supply for irrigation in the area for many years despite its increasing po llution. T he potential spreading of gastro-intestinal diseases has been contained however, since the majority of crops grown in downstream farm land are paddy and nonleaf vegetables and there is diversion of additional irrigation water to the area from a canal to the west of the city via the Mae Kha main drain . The water from the drain entering the Ping River in t he dry season has a BOD of less than 20 mg/ L as a result of self purification. The Mae Ping River is used for subsistence fishing and riverbank cultivation , bathing and household laundering. The people involved have complained of mal-odour of the river water and of skin disease resulting from its use.

3.5 Wastewater Management Philosophy

3.5.1 Domestic Wastewaters Low technology systems such as vaults or pit latrines were rejected from considerations of aesthetic health and long term community acceptability. They were also not compatible with present practice or aspirations. Cistern flush systems were

EXISTING PROBLEMS

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Figure 3. Progressive stage of system upgrading.

34

WATER March, 1986

considered unsatisf!ctory since many areas have poor water supply and would be subj ect to periodic failures in water pressure, also , they are not general community practice in the cities. It was also considered that a cistern flush system would lead to increased septic discharges which would more rapidly exceed the absorptive capacity of soils leading to increased discharge to drains and hence to more costly sewerage reticulation to alleviate this problem.

As the upgrading of street and main stormwater drains and the improvement of solid waste disposal forms part of the overall project, then t-h e removal of septic tank effluent from the urban areas should utilise the larger and cleaner drains.

However to prevent further pollution of main open drains it is essential that these flows be intercepted and treated before discharge into them.

The recommended strategy was to continue development of the prevailing system of pour-flu sh squat plate two chamber septic system with on-site absorption and when absorption is inadequate to connect overflows to street storm drains. The waterways are to be kept clean by a programme of routine maintenance and dry weather flows are to be collected and treated. (See Figure 3).

This system was adopted as being: • understood and socially acceptable; • capable of being maintained ; • affordable by users and Municipality; • capable of progressive development.

The treatment of discharged wastewater was considered essential. This was based mainly on environmental and social grounds which included: • removal of offensive conditions which reduce propeity values; • decrease in the risk of waterborne disease; • improvement of the recreational and aesthetic value of waterways so as to beautify the cities and attract tourism; • improvement of the quality of receiving waters used for fish culture , irrigation and human consumption ; • the capability to accept further residen~ tial and industrial growth .

3.5.2 Industrial and Institutional Wastewater The principal sources of wastewater, other than domestic, include hospitals, · military establishments, schools and universities, hotels and small scale food industries. Current wastewater disposal practices include the discharge of waste directly to the stormwater system or septic tanks with on-site disposal. Certain large institutions have full treatment systems such as oxidation ponds, an activated sludge plant or an extended aeration plant.

Many of the full treatment systems were not operating. Industrial wastewater producers were subj ect to the ' Water Quality Standard for Industrial Waste Effluent' produced and controlled by the Ministry of Industry. It is intended that these regulations be progressively applied , by the relevant authorities, to control the quality of effluent discharged to watercourses from industrial producers.

3.6 Wastewater Generation and Characteristics There are intrinsic differences between the two cities in the type of population to be served. The population of Khon Kaen is mainly residential with few tourists and visitors. Khon Kaen piped water reticulation has the capacity to supply only the central part of the city. The groundwater is brackish in many areas and not extensively used. Some larger institutions have their own water supply system and wastewater treatment plants.

Chiang Mai has a high tourist and visitor population. Investigations indicated a higher than average per capita water consumption. Almost the entire area of Chiang Mai municipality has access to a piped water supply and groundwater is abundant and of good quality.

Measurements of the volume and quantity of wastewater entering a street drain ·were made on two occasions in dry weather at locations throughout the drainage system in both cities .

In Khon Kaen results indicated a direct correlation between wastewater flow and the residential population of the street drain catchment. A 1984 output of 192 L/ d of wastewater per resident was arrived at for Khon Kaen. This equates to 750'/o of measured per capita water consumption figures provided by the town water works. The wastewater output figure was increased for design purposes to 215 L/HD/ d in the year 200 1 on the following bases: • Increased density of development; • A decrease in general permeability of the area due to building and hence a decrease in effluent percolation; • An increase in direct connections of septic tank outlets to the street drains; • Improvements of the town water supply; • Increase in non-domestic wastewater output.

An average wastewater strength of 110 mg / L BODs was obtained by direct measurements of dry weather flow in the street drains. The wastewater strength figure was increased for design purposes to 160 mg/ L BODs in the year 2001 on the following bases: • The new interceptor sewers would greatly decrease travelling time and lower the degree of biodegradation and absorption of wastewater discharged.

•· The increase in the number of septic tank overflows connected directly to street drains.

Growth rates to predict future residential populations were made available by the Department of Town Country Planning on an area basis for the city.

In Chiang Mai results of the wastewater survey indicated the larger influence of tourist accommodation and support establishments on wastewater flow. Such infrastructure information was surveyed for the specific areas use for the wastewater survey as its location is not available through any other source. Only permanent residential population figures and their growth rate are readily available for the prediction of future flow from any area of Chiang Mai city. By classification of surveyed areas into low, medium and high tourism areas a separate per capita wastewater output figure was arrived at

for each of the three classifications related only to permaqent residential populations. For forecasting, the relationship between residential population and gross wastewater output was assumed constant on the basis that an area of high tourism would: • Attract service related industries which increase the permanent residential population.

• Attract an increase in residential population to staff the tourist hotels.

• Attract tourist related retail establishments which are mainly shophouses.

Design figures for per capita wastewater output in 2001 of 196, 355, 383 L/Ha/ d for low, medium and high tourism areas respectively were adopted. Future wastewater strengths in Chiang Mai of 120 mg/ L BODs were adopted after consideration of future water consumption.

3.7 Wastewater Conveyance Systems

After consideration of various systems, including flushing with irrigation water from outside the system, it was decided to remove wastewater from the main drains by the provision of interceptor sewers along each side of the main drains. These sewers intercept wastewater discharging from street drains. The interceptor sewers were designed to carry peak dry weather flow without surcharging and are set lower than the incoming street drains.

Sewer grading was carefully analysed to obtain self-cleansing action in dry weather conditions.

For wet weather conditions the interceptors are provided with side overflow weirs to allow excess discharge into the main drain, thus avoiding the need to size the interceptors for storm runoff. Under these conditions wastewater and stormwater are mixed and significantly diluted which was agreed with Royal Thai Government as an acceptable condition.

The interceptor sewers in Khon Kaen carry wastewater to a downstream pumping station and wastewater treatment plant. In Chiang Mai the interceptor sewers serve to divert wastewater from the central 4.5 km section of the main drain (Mae Khu) and to discharge back to the Mae Kha downstream for the time being.

A treatment plant is planned for the future but no location or design studies have been done.

In both cities the installation of the interceptor sewers required land acquisition to widen the main drain channel reserve.

In central Chiang Mai land costs are high and it was more economic to locate most of the interceptor sewer in road reserves near the main channel. In Khon Kaen and the outer parts of Chiang Mai the interceptor sewers are located immediately adjacent to the main drain.

3.8 Wastewater Treatment at Khon Kaen

At the time of design, effluent standards from domestic wastewater plants were not subject to direct control by legal statute. Receiving waters were however governed by the National Environmental Board Criteria for Inland Freshwater Quality. A target standard of class 2 for the lake Bung Thung Sang was adopted to suit the requirement for fisheries purposes and .which would be of no detriment to its

receiving water, the Lam Phra Khu river, used for community water uses.

To determine the degree of treatment required for wastewater the inflow/ outflow for the lake over a typical year were considered. These indicated that during the dry period an almost full lake with no overflow can be expected. During this period the lake will become a maturation pond of some days detention. It was determined that the effluent from the treatment plants to the lake shall have a BODs (total) of 45 mg/ L with Suspended Solids less than 60 mg/ L. Studies of feasible treatment processes led to the conclusion hat for the degree of treatment required, waste stabilisation ponds were the preferred method of treatment.

An area of land reclaimed from the lake will be used for construction of the ponds .

Due to the depth of the Interceptor Sewers relative to the main drain and lake top water level it is necessary to lift, by pumping, the total interceptor sewer flow into the pond system with flow through and into the lake by gravity.

Pond hydraulic and biological loadings were determined on dry weather flow rates.

3.9 Future Wastewater Treatment Requirements at Khon Kaen

In 1985 after completion of design work the National Environment Board of Thailand adopted a 'Domestic Effluent Standard' which requires that the effluent discharge from a wastewater treatment plant catering for a 'population of more than 2500 be of higher quality than that proposed for Khon Kaen wastewater treatment ponds.

The efflueift standard to be met is 20 mg/ L BODs, 30 mg/ L Suspended Solids and 10 mg / L Organic-Nitrogen. A preliminary plan for a future system to upgrade the proposed ponds, which may be implemented in the future, has been put forward for consideration.

4. SONGKHLA FISHING PORT 4.1 Description of the Fishing Port

The existing fishing port at Songkhla is operated by the Fish Marketing Oranisation of Thailand (FMO). It is located on the shore of Songkhla Lake near to its outlet to the sea and is in the business centre of Songkhla city . Total fish landed at the port averages 500 tonnes/ day.

Fish landed along the shoreline of the Songkhla Lake has long created environmental problems in the lake and in Songkhla city. The capacity of the existing port is not adequate for the large number of fishing boats causing long waiting times and sometimes rotting of fish. In addition to the existing port's lack of landing facilities, other problems associated with the existing port such as traffic congestion, noise pollution and odour pollution to the adjacent business district were contributing factors to a decision to build a new port at Tha Sa-an.

Feasibility studies supplemented by an Environmental Impact Study led to approval to construct new port facilities and an Industrial/Commercial Development zone at Tha Sa-an also on the shore of WATER March, 1986 35

ty connections for aK other wastewater collection. Flows by gravity reticulation to two pumping stations and pumping to the inlet of the wastewater treatment plant.

Effluent from the treatment plant will discharge into Songkhla Lake. The gravity reticulation system was kept within the depth of fill, in order to minimise any problem of constructing sewers in the soft material of the bed of the lake.

Songkla Fishport 'cottage' industry fish processing.

Songkhla Lake. The new fishing port development comprises 3.5 Ha to be leased by the FMO to replace the existing fishing port and marketing area. An adjacent area of 19.5 Ha is planned for subdivision and development for fish processing industries, small scale industrial lots and shophouse and commercial development. The land for the whole port and commercial area is to be reclaimed from the lake, involving the placing of 2 to 2.5 million metres of fill.

4.2 Existing Wastewater Situation

The existing landing area and adjacent fish processing and packaging areas use both fresh and seawater for cleaning and washing down. Wastewater is discharged directly by drains to the lake, in common with other parts of the city.

At present there is no provision for treatment of wastewater before discharge.

The holds of fishing boats are also washed out and discharged overboard in the vicinity of the port.

from fishing boats.

The collection and treatment of wastewater was designed for the specific characteristics of the following areas: • Covered fish unloading and selling areas: foul drainage and washdown of paved areas.

• FMO office building and cafeteria: foul drainage from buildings.

• Covered retail fish market : foul drainage and washdown from paved areas.

• Fish processing industrial zone: foul drainage from buildings.

• Commercial shophouses: overflow from septic tanks .

(See Figure 4).

4.4 Wastewater Conveyance System

A wastewater collection system in the landing area involved open floor channels for washwater collection and piped gravi-

SONGKHLA LAKE

4.3 Wastewater Management at New Port

Current environmental regulations require that all wastewater from the port and commercial/ industrial zone should be treated to a specified standard before discharge to the lake. Given the variety and quantity of wastewater from the development, conventional separate sewer and stormwater drain systems were feasible and were adopted for the 22 ha development. This was a significant technical departure from the combined drain systems normally used in the region.

Details covered in the design of the port area for operations such as fish unloading, sorting, cleaning and selling areas included: • Provision of grated stormwater drains in order to prevent solids flushing into the lake.

• Provision of grease traps on stormwater drainage from fish handling areas.

• Provision of on-shore toilet facilities.

• Provision for separate collection and treatment prior , to discharge to the lake, of any fish processing wastewater and washdown water from fish handling, landing and selling areas.

• Provision to receive pumped out waters 36

WATER March, 1986

4.5 Wastewater Generation and Characteristics Wastewaters from various sources at the existing port facilities were sampled and tested on two occa.-s, ions. A water consumption survey was also carried out.

Water is drawn from two sources, a town water supply and seawater from Songkhla Lake.

Wastewater flow from the port as a whole was measured and flows from individual activities were estimated.

Washdown by seawater was estimated by monitoring seawater pump flow rate and usage on different areas and related to unit area served per day . Processing water usages were monitored and related to tonnage of material processed.

Volumetric load from the new port area could then be predicted by use of these unit landed rates as the activities of fish landed, processing and selling were similar at the new and old ports.

Wastewater flow from shophouses was estimated as 65% of estimated potable water demand which is in line with other similar areas in the city. A desk study of projected staffing a11d facilities at all establishments in the port and commercial area was carried out to determine the potable water demand.

Wastewater f haracteristics obtained by testing samples from the existing port, washwater and process waters were combined with flow measurements to arrive at

100

200m

SCAL E

.,,,p•.·· · /,'·

: : .·. ·. ·; · ; :

...... .

SONGKHLA LAKE

Figure 4. Songkhla -

Songkhla Hew Fishing Port.

unit BOD loadings per square metre of area of washdown per day and per tonne of fish processed at the existing port.

Wastewater BOD loads generated at the new port facilities were calculated using these unit figures and the fact that a finite waste load is generated by a tonne of fish landed and processed, regardless of water usage.

Design wastewater flow and waste loadings used for the new port facilities are: - 1380 m3/ day Wastewater Flow BOD combined - 1348 mg/ L wastewater - 1860 kg/ day Total BOD loading Hourly peaking flow factor - 3 Hourly peaking BOD loading factor - 5 Other parameters of the waste load are as follows: pH- 7.1 SS - 3000 mg/ L Cl - 10 000 mg/ L Oil and Grease - 30-1000 mg/ L A treatability study for the combined wastewater samples was carried out by the Thai Scientific and Industrial Research Organsiation. The results show the waste to be readily biodegradable despite the very high content of oil, grease and chlorine.

4.6 Treatment of Wastewater

Three options were considered for the process of wastewater treatment: • Extended Aeration.

• High Rate Biological Filtration.

• Aerated Lagoons .

The extended aeration option was rejected because of a significantly higher capital and operating cost than the other two options.

SNOWY MOUNTAINS ENGINEERING CORPORATION. Continued from P. 15.

8. REFERENCES PROJECT REVIEW TEAM (1984) . Tanzania village water development project: evaluation , Final Report. Prepared for Ministry of Water and Energy, United Republic of Tanzania and Australian Development Assistance Bureau, Government of Australia.

SNOWY MOUNTAINS ENGINEERING CORPORATION (l 978). Singida Region water resources survey (7 vols.). Prepared for Australian Development Assistance Bureau.

WORLD BANK (1984). World development report 1984 . Oxford University Press.

WORLD HEALTH ORGANIZATION (1971).

International standards for drinking water.

APPENDIX COPY OF TYPICAL VILLAGE SURVEY RESULTS District: Ward: Village: Reference No.:

Singida Misughaa Ntuntu S 21

The aerated lagoon option was adopted due to the following: • Least capital cost.

• A greater reliability to achieve predicted effluent quality. Lower input from operational and maintenance personnel was an advantage as frequency and quality of maintenance could not be guaranteed.

• Requires fewer items of mechanical equipment with lower foreign cost.

• The facility to reduce operating costs with lower plant loadings when fishing · and port usage decrease during monsoon periods.

• Uses a treatment sys tem already established in Thailand for treating industrial wastewater.

The aerated lagoon system to be constructed comprises a primary lagoon of seven days detention followed in series by a secondary lagoon also of seven days detention.

5. CONCLUSION On completion of the wastewater components of the project an overall improvement in the environment of the cities is expected. The most tangible results of this improvement will be a more productive use of waterways in Khon Kaen and an increase in amenity in Chiang Mai. In Songkhla the full treatment of wastes from the fishing port and the industrial and commercial area will significantly reduce pollution loading into the environmentally sensitive Songkhla Lake.

By providing a maintainable wastewater infrastructure in the cities an example has been set of design criteria for further expansion and the basis for establishing a management structure to operate and maintain these assets. The Project will have promoted the ideas of pollution control techniques and the concept of affor-

ACKNOWLEDGEMENT

The design phase of the project was funded by the Australian Development Assistance Bureau. The authors acknowledge the kind permission of the Bureau and the Royal Thai Government to publish this paper.

REFERENCES MINISTRY OF INTERIOR , THAILAND (1983). ' Report of Feasibility Studies for Regional Cities Development' prepared by Sinclair Knight & Partners Pty . Ltd. (Australia), Team Consulting Engineers Co. Ltd. (Thailand), Asian Engineering Consu ltants Corp. Ltd. (Thailand) and Sumet Jumsai Associates Co. Ltd. (Thailand).

MINISTRY OF INTERIOR THAILAND (1985).

'Technical Paper No. 16 on Design Criteria and Procedures for Wastewater, Songkhla Fish Port for Regional Cities Development' prepared by Sinclair Knight & Partners Pty. Ltd. (Australia), Team Consulting Engineers Co. Ltd . (Thailand), Asian Engineering Consu ltants Corp. Ltd. (Thailand) and Sumet Jumsai Associates Co. Ltd. (Thailand).

MINISTRY OF INTERIOR THAILAND (1985) 'Technical Paper No. 13 on Design Criteria and Procedures for Waste Water in Khon Kaen for Regional Cities Development' prepared by Sinclair Knight & Partners Pty. Ltd. (Australia), Team Consulting Engineers Co. Ltd . (Thailand), Asian Engin eeri ng Consultants Corp. Ltd. (Thailand) and Sumet Jumsai Associates Co. Ltd. (Thailand).

MINISTRY OF INTERIOR THAILAND (1984) ' Technical Paper No. 2 on Survey of Wastewater Services in Chiang Mai and Khon Kaen for Regional Cities Development' prepared by Sinclair Knight & Partners Pty. Ltd. (Australia), Team Consulting Engineers Co. Ltd . (Thailand), Asian E nginq, ring Consultants Corp. Ltd. (Thailand) and Sumet Jumsai Associates Co . Ltd. (Thailand).

•

SWL m: 70 Yield L/h: 8645 File Reference No .: 7/ 126 Geophysical Survey: Mgego 19 Sept 1970

VILLAGE DATA Families: 596 Cattle: 831 Sheep: 272 Goats: 538

Remarks

DETAILS OF MAIN WATER SUPPLY Source: Borehole Method of Extraction: Lombardini I cyl. diesel, 2 V drive, Mono B 630 pump Storage: 45 500 L concrete tank Distribution : 6 outlets plus cattle trough Reliability: Good Alternatives: Shallow wells with SWL 0.5-0.8 m. Inflow about 8 L/ minute Distance Village - Collection Point: 800 m Collection time: 1 ½ -2 hours Chemical Quality (ppm): F 0.9 Fe 0.37 NO, 6.3 pH 6.5 Conductivity: 250 fVS/ cm at 23 °C TDS (PPM): 790

Rising main and distribution main to Ngayo require repair. No fuel has been available since April as pump attendendant is alleged to be selling fuel to maize grinding plant in village.

Completion form and pump test record • available.

TOM BEER. Continued from P. 31.

The Author thanks Binnie and Partners for their assistance and permission to publish this paper.

REFERENCES Problems Insufficient Water Contamination Too far from Homes Fuel Shortage · Poor Organisation X Poor Maintenance

GENERAL DATA Map Reference: Singida 34°59'ES Interviewer: DC/ HM 8/ 9/ 77 Air Photo Ref. : Not available Informant : Chairman

dable and appropriate sanitation in the cities.

Borehole Data Borehole No.: 63/73 Depth m: 159 Water Struck m: 100

X

X

CHEN JI-YU , YUN CAI-XING and XU HAIGEN (1982). The Model of Development of the Chang Jiang estuary during the last 2000 years, in Estuarine Comparisons, 655-666. (Academic Press, New York} HOLEMAN, J. N. (1968). The Sediment Yield of Major Rivers of the World, Water Resources Res., 4, 737-74 1.

SMART, P. L. and I. M. S. LAIDLAW (1977). An evaluation of some fluorescent dyes for water• tracing, Water Resources Res., 13, 15-33.

WATER March, 1986

37

VILLAGE WATER SUPPLIES IN BURMA H. F. Eggington ABSTRACT A Burmese initiative in development of rural village water supplies is being assisted by the Australian Development Asistance Bureau working through consulting engineers, Coffey and Partners Pty. Ltd .

The project commenced as one involving only the supply of machines and materials to assist the Rural Water Supply Division of the Burmese Agricultural Mechanisation Department to construct tubewells in 3100 rural villages in the Dry Zone of Central Burma and to provide piped water supplies to another 100 villages by pumping from the Irrawaddy River. A need for technical assistance and training in modern groundwater development and pipe laying technologies, brought a change in thrust.

Three Australian advisers are assisting Burmese engineers to construct the tubewells and equip them with pumps and engines. Pipe laying and civil construction skills are being developed in Burmese crews.

The engineering achievements are significant but more important are the technical and managerial skills developed in the Burmese water authority and the humanitarian benefits gained by the village people.

BACKGROUND As early as 1952 the newly formed Burmese National Government initiated a programme to improve rural water supplies. Recognising the economic advantages of the inherently 'safe' groundwater sources which are available to the majority of Burmese rural villages, the emphasis was on provision of tubewells .

Restrictions on the availability of the foreign currency required for the purchase of drilling machinery, pumping equipment and construction materials slowed but did not stop the programme. A change of government in 1962 and government reforms resulting in the formation of the Socialist Republic of the Union of Burma in 1974, brought a policy of minimising foreign involvement and maximising indigenous knowledge and skills. Reforms in the mid 1970s moved the emphasis of economic policy to an agricultural base. International agencies concerned with the welfare of women and children and with rural health, saw a need for rural development if the desired agricultural based benefits were to accrue .

In 1974 the World Health Organisation suggested that the Burmese Government formulate rural water supply projects for funding assistance from international agencies . A consultant from W.H.O., in 1976 worked with the Rural Water Supply Division (R.W.S.D.) of the Burmese Agricultural Mechanisation Department (A.M.D.) to prepare documentation for assistance.

Burma's third Four Year Plan, commencing in 1978, included objectives requiring the reduction of the physical dif-

ficulties of fetching water , and the improvement of health and nutrition, through the provision of adequate safe water. The Burmese targets for its 'International Drinking Water Supply and Sanitation Decade' programme involves the completion of water supply and sanitation works to serve 500Jo of the country's population by 1990. This includes the construction of 13 500 new village water supplies during the decade.

The Australian Programme was designed to contribute to this comprehensive plan. The Australian Programme objectives involved: • construction of 1700 rural tu bewells • extension of an existing piped water scheme with the aim of improving socio-economic conditions of the population of the Dry Zone of Central Burma, Figure 1. The project is being implemented by the Australian Development Assistance Bureau (A.D.A.B.) through its project management in Burma provided by consulting engineers, Coffey and Partners Pty . Ltd. The formal agreement between the Australian and Burmese Governments expects that an estimated two million people will be provided with 10 gallons per head per day of safe domestic water and that this will reduce the incidence of water related diseases. A joint programme for tubewell construction with the United Nations Childrens Fund (UNICEF) participating, was decided upon. The joint objectives were set at the construction of 3100 tubewells, each to be equipped with a pump and engine and each to be capable of supplying the village with 10 gallons/ head/ day of safe drinking water.

Since a village typically has a population of about 1000 persons, a village tubewell yielding 2500 gallons per hour will satisfy the requirement with pumping being necessary for only four hours per day.

Well yields of this magnitude or greater are commonly available.

IMPLEMENTATION PHILOSOPHY The implementation of the project encountered some severe constraints: • Project hardware must be purchased from international markets, markets which supply equipment and materials in keeping with the technology of the 1970s and 1980s. The Burmese have innovative skills which are highly developed but their technology very largely is based on the state-of-the-art in water supply and well construction as existed prior to 1930. The Burmese Government Policy of 'minimising foreign involvement' results in a constraint on entry and movement of foreign personnel and makes it difficult to have requisite skills available at the opportune time to achieve the transfer of technology necessary to allow the effective use of internationally supplied machines, equipment and materials.

Frank Eggington is a mechanical engineer who has specialised in drilling and training activities, usually in conjunction with water resource evaluation and development. He is the Project Manager of the Burma Village H.F. Eggington Water Supply Project, an Australian Development Assistance Bureau project being managed in Burma by Coffey and Partners Pty. Ltd. Frank's experience includes development of rural and town water supplies in Malaysia and the Philippines, as well as Australia. In the Northern Territory, he occupied the positions of Principal Engineer, Groundwater, and Assistant Secretary, Water Resources. In South East Asia he has managed groundwater based water supply projects and others, like that in Burma, which involved both groundwater and surface water development. Frank is the editor and principal author of the 'Australian Drillers Guide'.

• A Burmese practice of setting high short-term targets and then trying to force the pace necessary to achieve the targets, results in overloading and lack of maintenance of machinery, factors which inevitably bring breakdowns and an inability to confinue to the longer term targets.

• Some products, which either are in short supply or have a priority allocation to the generation of export income (e.g. petroleum fuels and cement), may not be available when required.

The initial intention of the Project Design was to specify equipment and • materials, in consultation with Burmese Authorities; to provide the agreed goods and, in conjunction with appropriate Burmese expertise, to monitor and evaluate the use of the goods and the results achieved.

In the light of the constraints which became evident as the Project got under way, a fresh implementation philosophy became necessary.

• Since the specifications for machinery to be provided and the intended methods of operation advanced can be coloured by short-term targets or even by factors outside the project, careful consideration of project needs and the specification of machines, equipment and methods to best satisfy the needs became the prime criteria.

• The supply contracts were extended to provide comprehensive training not only in plant operation and assembly of material but also in the technology behind the construction processes. Trainers entering the country as part of a supply package can be accepted more readily than trainers imported to provide a 'transfer of technology' in a discipline in WATER March, 1986 39

which existing competence must be assumed.

• Continuing short-falls in achievement of targets were correctly identified as being a result of down-time on plant worn or damaged by lack of maintenance or improper practices. With the accumulation of evidence, the need for strictly observed maintenance schedules and increased operator understanding as well as skill, became acknowledged.

• During the period that Burmese technologists have been exposed to foreign advice and instruction they have come to expect a degree of denigration of Burmese skills and some lack of understanding of the Burmese position and the constraints placed on Burmese officials. In selecting advisers to work in Burma on this project, people capable of achieving understanding of the sociology . of the Burmese work place were chosen.

• Construction methods and techniques advocated were selected with a mind to maximising the use of readily available Burmese facilities and materials, minimising the use of scarce or potential export earning materials, and trending towards the elimination of a need for imported materials or components .

• The terms of reference for this project require that foreign advisers be seen as advisers, not operators or managers. The management of the project is the responsibility of the Burmese Ministry of Agriculture and Forests working through the Agriculture Mechanisation Department and the Rural Water Supply Division.

On a day to day basis the project is managed by the R.W.S.D. with the Director and Administrative organisation resident in Rangoon and with regional management by four Drilling Station Managers and a Civil Construction Site Engineer at field centres. The Australian advisory staff numbers three, in the disciplines of construction engineering, hydrogeology and maintenance mechanics . The resident advisors are supported by expertise introduced either as a component of equipment supply or during short visits of consulting personnel coming to satisfy requirement for development of skills or evaluation of a need.

A project activity may stem from a Burmese initiative or may result from advice to the Burmese Department from a foreign advisor. But in either case the activity is initiated only after appropriate higher Burmese approval is obtained and the activity is incorporated in the recognised programme of the project. The Memorandum of Understanding signed by the co-operating governments, defines the parties involved and the activities to be undertaken. Project activity cannot extend outside the terms of reference imposed by this document.

PROJECT ACTIVITY The major thrust of the project, and the most effective, is toward the construction of village tubewells. A tubewell installation activity typically includes: the selection of a site, to satisfy the needs of potential users and to gain access to a groundwater reservoir; the drilling of the well us40

WATER March, 1986

94°

102°

2a 0

28°

INDIA 26°

26°

24°

24°

22°

20°

18°

18°

BAY

Or BENGAL

THAILAND 16°

16°

[:87

LiJ

14°

12°

Project Area (Dry Zone of Burma)

SAGAING PAKOKKU • MAGWE MEIKTILA

14°

RW.S.D .

Drilling Stations

ANDAMAN SEA

Figure 1. Burma Village Water Supply Project -

ing drilling equipment operated by R.W.S.D. crews; the construction of a ground tank and pump house by the villagers; the installation and testing of pumping equipment and engine by A.M.D. crews . The pump engine is operated by a village appointed operator and maintained by visiting A.M.D. mechanics.

Village Reticulation Schemes, as an extension to the village tubewell construction activity, provide water to a small group of villages centred on one higher yielding tubewell.

A minor thrust, but one which has proved time consuming and inordinately expensive, is towards the construction of a piped water scheme to deliver water from the Irrawaddy River to some 65 villages in an area with inadequate access to groundwater.

location plan.

The skills and equipment involved in each of the above activities are discussed below.

GROUNDWATER DEVELOPMENT Well site selection

Villages to receive wells are selected on the basis of need for water supply, health problems, willingness of the villagers to contribute, distance to present water supply and availability of a superior water source.

The siting of the well and the assessment of the availability of a water source are duties of the hydrogeological staff of R.W.S.D. A number of Hydrogeologists, after taking out a degree at Rangoon University

are given post graduate training, by the project, in Australia; and all are given onjob training in the application of hydrogeological principles to the Dry Zone of Central Burma by the Resident H ydrogeologist. This superimposition of skills upon knowledge has proved to be a most effective trafning input. The success rate for selection and design of wells is extremely good , probably less th an I in 100 wells are unsuccessful for hydrogeological reasons.

Drilling Operation

Project statisics show that 900Jo of holes drilled result in successful wells. An estimated 9 out of each 100 wells are not successful because of drilling or well completion problems.

The R.W.S .D . has considerable experience in water well construction.

Rotary drilling using standard rotary table rigs and mud fluid circulation has been practised in Burma for over 50 years. A difficulty arises in that the large diameter hole adopted in Burma is not efficiently drilled by modern machinery which is designed for smaller holes and equipped with low capacity circulation pumps.

Poor hole cleaning and a lack of compensating skills in drilling fluid formulation and treatment, bring high wear rates on equipment and exaggerated down-hole problems. Because of their long experience and their confidence in the competence of local skills the Burmese officers responsible for the drilling programme have tended to regard training in drilling as an unnecessary introduction of foreign personnel and skills. This attitude is changing and training of drillers both in Australia and in Burma has commenced.

The many tasks contributing to a successful well may be viewed as making up a set of interlocking systems. Variations in one or even a number of components of the systems may not produce significant benefits. The entire set of systems must be adjusted. To achieve a revolutionary and far reaching adjustment in an organisation that is biased strongly towards maintaining traditional procedures has been a major challenge. Specific problems encountered in Burma, such as circulation loss to incompetent low pressure formations and hydration and swelling of water . sensitive shales, are commonly overcome using techniques not usually available to Burmese drillers. For example, the high cost of large air compressors coupled with an inability to suppl y fuel in the quantities required to drive such compressors, render the use of air circulation an option which is not available. Some chemicals and many drilling materials cannot be provided from Burmese sources, restrictions on the availability of foreign currency prevent them being imported. The innovative approach of Burmese technicians results in the local manufacture of many spare parts but sometimes the ingenuity displayed is defeated by a lack of understanding of the reasons for some small detailed feature of the part.

Well Completion

Water well drilling in Burma uses skills drawn from oil drilling operations. Well

completion operations do not have a Burmese skill background a nd consequently receive Jess than optimum attention. Early water well drilling used cable tool percussion techniques and enabled cable tool well development procedures to be used. With the introduction of rotary drills, well development became simply air- lift pumping with some stimulation by air surgi ng. The efficacy of this technique, particularly in deeper wells is open to question but while the low yields req uired are being achieved, it is difficult to introduce improved techniques.

The clogging of fine screens by the cutting laden drilling fluids remaining in the well at the time of inserting casing has caused low yields, but the solution in this case lies in cleaning up the drilling fluid rather than in changes to the development procedures.

Another result of the ease with which the low yields required are achieved is a lack of interest in comprehensive testing of wells . Again , a lack of well test data may not have any significant short-term consequences, but in the longer term the Burmese Hydrogeologists are being denied access to data whic h will enable them to define aquifer parameters and assess available water resources.

13th century Pagonda in Pagan in the centre of the project area.

Ground tank and pump house construction

Following a recognition that people will value only those things which have been acquired at some cost, Burmese authorities wisely insist that the well pump a nd engine only be installed after the villagers have made their contribution by building a ground tank and pump house.

These are built to a design set down by the R.W.S. D. Finance, supply of materials, and availability of labour to build the structures are the responsibility of the villagers although A.M.D. does assist by making an allocation of cement at government controlled prices.

Pump installation

Once the villagers have made their contribution, the A.M.D. installation crews install a pump and engine suited to the yield of the well . The yield is estimated from the flow of water produced during air-lift development. The installation skills exist as a result of the effective training given by the Australian pump supplie'r. The helical rotor pumps being used

on this project are new to Burma.

Thorough training of both installation and maintenance crews has established sound working procedures.

Operation, servicing and maintenance of village pumps

A pump operator, appointed by the Village, is trained by the installation crew in the operation and servicing of the pump . In general the operator takes considerable pride in having the responsibility for what is often the village' s most significant asset, and attends to his duties with care. Maintenance is provided during periodic visits of an A.M .D. maintenance crew. Like all maintenance activity in Burma, any work which requires the _consumption of stores is likely to be avoided .

The conservation of stores understandably is an important consideration in a country where funds to permit replacement may not be available. But fa ilure to replace filters or wearing components leaves the pump and engine without desirable maintenance and leads to reduced engine life .

Construction reticulations

of

small

inter-village

Circumstances arise when the construction of a well at a village for the exclusive use of that village, is not feasible. Two reasons for this are common: (1) Not every village has direct access to a suitable groundwater source although water may be available at an adjacent village.

(2) In some areas, particularly where the useful aquifers are at great depth, the costs of co~struction of a water supply canno t be justified if only one village is to benefit. Costs of reticulation to adjacent villages can be less than the cost of another well.

Local reticulation schemes replace the usual gro und tank with an elevated tank and the well pump is selected to accommodate the additional pumping head.

From the elevated tank, water is reticulated , usually through polythene pipe lines, to ground tanks at suitably situate~ nearby villages. Frequently advantage 1s taken of the opportunity to establish additional standpipes allowing access to water at more than one point in each village.

SURFACE WATER DEVELOPMENT Much of the arid central region of Burma has access to potable gro undwater and where available this source has proved to be an effective and efficient method of providing water to the scattered small villages. While little is known about the potential yield of the dry zone aquifers, general considerations suggest that the groundwater source is unlikely to be depleted by the low demand at village tubewells.

However there are areas where suitable groundwater is not accessible. As the dry zone is traversed by one of the world's major rivers, the Irrawaddy, development of supplies based on pumping or diversion from the river is an obvious alternative .

Surface water Jacks two of the signifiW ATER March, 1986

41

cant advantages of groundwater: • Surface water is available only at discrete locations, from permanent streams or from natural or artificial ponds, from these locations the water must be reticulated to the user. Groundwater often is available from aquifers existing below the point of use, reticulation costs are confined to those incurred in providing and pumping the tubewell.

• Surface waters are subject to pollution and frequently must be treated to remove turbidity as well as bacterial contamination. Groundwater usually is free of turbidity and pathogenic organisms (although it is more likely to have an unacceptably high chemical content).

It is these two features that in Central Burma make groundwater development much more appropriate. Surface water reticulation involves two significant factors.

• The costs of piping and pumping from the Irrawaddy River to villages remote from the river, and at greater elevations.

• The technical feasibility and costs of treating river water to remove turbidity and bacterial contamination, when chemical methods are not suitable, as the necessary chemicals are not available.

These factors make surface water development of the Irrawaddy water expensive and not cost effective. The development can only be justified on humanitarian grounds. Whereas the cost of establishing potable water supply to a Burmese rural village runs at about US$20 per head of population served when a groundwater source is used, the cost can rise to in excess of US$100 per head of population served when river water is reticulated over the considerable distances involved.

Surface water quality determination

Surface water not only is likely to be inferior in quality but the quality is also likely to vary with the seasons. Treatment and, to some extent, pumping equipment specification depend on an accurate knowledge of the water quality. In Burma little information has been collected on water quality and the facilities for water sampling and analysis are not readily available. The project is supplying sampling and analysis equipment and is assisting in training personnel to use the equipment.

Water Treatment

Long-term supply of potable water is only possible if the local community desires to have the treatment facilities established, the operating personnel are motivated to provide water of the intended quality and the facilities can be operated and maintained using materials and components available in Burma. The design and construction of a plant which will operate using only material sourced in Burma is possible, but the existence of attitudes guaranteeing the operation of the plant to produce water of desirable quality, is by no means certain.

The first question to be answered is: what is the definition of 'desirable quality'? In many communities public 42

WATER March, 1986

opinion forces the supply of water which is completely free of any contaminant which could possible constitute a health risk or offend by virtue of turbidity, colour, taste, smell or feel. Acceptable waters must be neither incrusting nor corrosive.

Rural communities in 'undeveloped' countries rarely exert a critical public opinion in respect of water quality . Waters with some 'taste' often are preferred.

Some turbidity or colour may not be a concern. Highly brackish or saline waters will be rejected but the community often tolerates bacterial contamination, either boiling the water or 'accepting' diarrhoea and similar afflications as 'normal'. In these circumstances the community pressure on the water authority to maintain a high-quality water does not exist and the operating staff adjusts practices in the treatment plant to avoid 'unnecessary' treatment.

Plants constructed in the past provide examples of dosing and coagulation tanks which are completely full of silt, and reticulated supplies which, are in fact, raw water which has merely benefitted by some primary settlement of suspended material.

Funds should not be expended on works which will not operate to contribute to the objectives of the project and, in particular, funds must not be wasted on monuments which will not be used. This requirement causes the designers and constructors of works for projects of this type to become involved with social and community matters as well as the obvious engineering and administrative concerns.

The facilities provided must be in a form desired by the users and their operation must only require the use of technology available and willingly contributed by the intended users of the facility .

Pipeline Construction

Recent development in pipeline materials and jointing methods have made pipe laying c':leaper and easier. Burmese practice has not kept up with these changes. The laying of pipes on this project did not proceed until suitable engineers qualified to instruct in field practices contributing to pipe laying, could gain approval for entry to Burma.

Following instruction , Burmese engineers rapidly mastered the techniques and pipe laying is proceeding well. Plastic and cement/concrete piping are subject to deterioration with handling and with storage in hot dry climates. The pipeline design must de-rate the operating pressures accordingly. The pressure testing of pipeing must be maintained rigorously.

All these factors become critical when construction work is being carried out by personnel lacking the experience normally assured to exist in a pipe laying crew. So that the benefiting villagers may be seen to be contributing to the construction of their water supply, villages are required to contribute labour to work on that section of the pipeline adjacent to the village.

Burmese villagers have never so much as seen pipe of the type being laid by this project.

Pipelaying in the Tuang Zin W. S. Scheme.

Even the operation of excavating and pipe handling machinery brings problems peculiar to pipe work, and difficulties outside the experience of operators using similar machinery on another application.

Without experienced labour, construction schedules are delayed by unexpected damage and high rates of wear of plant and equipment. Delayed schedules result in the trench lying open, subject to the effects of wind and rain.

Reservoir Construction

Pipeline schemes require considerable civil construction works not only at the treatment works but 'also for distribution reservoirs and pumping stations along the pipelines.

The route of the Burmese pipeline traverses country subject to earthquakes.

All reservoir and tank designs must allow for earthquake loadings. The desirable light section reinforced concrete construction is new to Burmese engineers who traditionally have used massive concrete in their much smaller structures. The required changes in construction methods brought a requirement for new or more refined skills in foundation preparation, control over concrete batching , layout of discrete slabs/segments with provision of satisfactory water stops.

Some foreigner's reservations concerning an ability to finish surfaces by hand and to achieve continuous concrete placement when the concrete is delivered by women each carrying about 20 kilograms of concrete in a lined cane baseket balanced on her head, were dispelled when the potential of the large labour force became clear. Fastidious attention to detail by the stone masons building reservoir walls has produced excellent reinforced masonry walls providing adequate ability to handle earthquake accelerations.

All reservoirs are being roofed. Roofing iron is being supplied from Australia for installation on trusses using Burmese timber to Construction Corporation designs.

Pump House/ Operator Accommodation

Pump houses, and all personnel housing, required for the period piped water supply scheme are being constructed to

Burmese designs by the Burmese Construction Corporation. Each pump house floor layout provides for two electrically driven centrifugal pumps. Each pump is designed to provide the full output of the station; the second pump provides lOOOJo standby. Fully automatic switching is being provided with pump operation being controlled by floats at the upstream and downstream reservoirs. Protection devices and relays bring in the standby pump if the initial pump ceases to operate. Warning lamps indicate the nature of any fault and what action, if any , the operator should take.

Housing for the operators and their families is being provided at each pumping station. Operator houses are of reinforced concrete with masonry in-fill construction, similar to the pump houses, but rather than the imported zincalume roofing used over the pumps, the operators will live under local ceramic tiles.

A communication cable laid in the pipe trench connects the automatic switchgear controlgear assemblies to the reservoirs.

Two circuits in the cable will be used for telephone connections between pumping stations and the treatment works.

Electric Power

Electricity was chosen rather than diesel power even for the remote stations along the line because of the shortage of diesel fuel in Burma and the unreliability of its supply. The use of electricity provides a side benefit in that the new power lines necessary will provide electricity for lighting and cooking in the villages along the pipelines. The villagers in the dry zone of Burma are not only without secure water supplies but also without sufficient fuel for cooking.

PROJECT MANAGEMENT At the time the Burma Village Water Supply Project commenced the R.W.S.D. was a relatively small organisation with an approved staffing of 469 . The style of management involved working towards targets approved by higher authority. The targets and the routes to be followed in reaching them were all laid down with the result that activities and even procedures could not be varied.

The foreign aid funding for the project brought an influx of equipment and techniques new to Burma. Hydrogeological survey and laboratory equipment, drilling machines, deep well pumping units, pipeline and construction materials and a host of support equipment and vehicles, created a demand for new skills and, indeed, a different way of thinking about the most suitable method of achieving the targets.

As the project proceeded, the potential impact of differing perceptions of the water uses upon the achievements of the project became obvious. It became clear that people will not change their habits and gain all the potential benefits of a new safe water supply just because the water is available. The people must be shown the benefits of using the superior water and must be taught how to look after the water facility so that the benefits continue to be available.

The trammg available to R.W.S.D. staff was increased. Both overseas and incountry training courses are offered. The R.W.S.D. is being provided with a wide range of brochures, manuals, journals and teaching guides.

To handle this project the R.W.S.D. approved staffing level has been lifted from 469 to 1416. R.W.S.D . personnel have gained skills in manpower planning as well as in the many technologies involved in the project. An ability important in the Burmese environment and gained through the project, is that of cooperating and co-ordinating with related organisations, both national and foreign.

The project has thus fostered the growth of the implementing organisation, in size, in capability and in confidence.

The measure of this growth is seen in a new found skill to examine objectives, detect desirable changes to accommodate the improved understanding of the peoples needs, and re-orient activities in a cybernetic fashion to address this identification of objectives. Growth of this type is seen at all levels in the organisation with increased responsibility for decision making stimulating development of personal skills.

To complement developing managerial skills, supervisory personnel are learning to use the tools of management. A monitoring and evaluation phase of the project introduced skills during short term visits to the project by the Australian Monitoring and Evaluation Consortium.

With these skills and other planning techniques being introduced, the management team is now fitted to undertake the design, planning and consortium of water supply development projects of diverse types and sizes.

There is an increasing awareness of a need for 'water-use management'. The capital costs of establishing water supplies are great. Since nearly all the suppies developed by this project require that water be pumped, operating costs are significant. Traditional water supplies are drawn by hand from shallow wells, ponds and streams or rivers. Consequently, although the dry zone community views water as a priceless possession - an often quoted expression states that 'water is preferred over gold' - the community is not accustomed to paying for its water.

Village pe.ople do not see spilt or contaminated water as being the loss of a -.:ommodity which has been an economic cost to them.

For the higher order project objectives to be achieved, the water provided must be kept uncontaminated and used liberally to the exclusion of unsafe waters, for drinking, cooking and bathing. A minimum use for health reasons has been set at 10 gallons per head per day but it is recognised that water use is only one factor, good sanitary practices and healthy living environment must also be achieved.

Water use management and even hygienic care of the water storage and distribution standpipes and facilities fall within the terms of reference of the managing authority, the R.W.S.D., but health and sanitation matters do not.

The project has suffered from a

weakness in that its design did not involve a significant input from authorities working in fields of sanitation and health education. Complementary activities by the United Nations Children's Fund and the World Health Organisation are overcoming the shortfall in this area. Similar projects should be defined, recognising the need for involvement in every aspect of those factors which affect or contribute to the planned objective.

PROJECT ACHIEVEMENTS The ambitious programme for construction of 3100 tubewells in villages scattered throughout the dry zone of Burma is being achieved. A surface water pipe water supply which is introducing many techniques new to Burma is progressing creditably although somewhat more slowly than planned . Both of these programmes provide safe water for drinking, cooking and bathing at the rate of 10 gallons per head per day to the people in the selected villages. The water supply certainly will reduce the daily drudgery of carrying water. Some indications of improving health and prosperity are appearing and considerable improvements are likely in time.

Most significantly, the village people, the users of the water supply, consider the project to be a success. A visitor to a village must be impressed by the obvious pride in the new water supply facility.

Villagers have formed Village Cooperatives to maijage the operation of their pump and tank installation. The cooperatives are accepting responsibility for setting water charges and collecting the money whj.ch pays the operators, and funds operating and maintenance costs.

But rewarding as these achievements are, greater value is seen in the development of technical and managerial expertise in the authority which will carry on the construction of water facilities. Burma is already well advanced towards achieving its objectives for provision of water supplies during the decade to 1990. The achievement of 'safe water for all of the country' by 2000, is a real possibility.

The extent of the impact on the health of rural villagers will depend on their acceptance and care of the facilities provided but more importantly on changes in their sanitation and hygiene practices.

SUBSCRIBERS PLEASE NOTE SUBSCRIPTIONS TO 'WATER' LAPSE WITH THE DECEMBER ISSUE AND RENEWALS ARE DUE IN JANUARY. FAILURE TO RENEW BY MARCH WILL MEAN DELETION FROM LISTING.

WATER March, 1986 43

HISTORICAL MALACCA SEWERAGE AND URBAN DRAINAGE STRATEGIES FOR THE FUTURE J. A. Crockett, T. J. Fricke, J. B. Murray and R. H. Smith INTRODUCTION Malacca has a central place in the history of South-East Asia. Founded by a Sumatran Prince about 1403 as the capital of the first Malay Empire, by the late 15th Century Malacca was being referred to by the Portuguese as the 'Venice of the East' and was in fact annexed by the Portuguese in 1511, conquered by the Dutch in 1641, and finally occupied by the British (after some 30 years of to-ing and fro-ing) in 1824. Thereafter the gradual federation of Malay states and Singapore proceeded and Malaysia was formed as an independent nation in 1963 .

The City of Malacca lies some 250 km north-west of Singapore on the west coast of Peninsular Malaysia at the mouth of the Malacca River. Today it is still one of the most important and interesting cities in Malaysia with well-developed commercial, manufacturing and tourist industries and a well-preserved Old Town dating back at least three centuries. Of its population of nearly a quarter million people, about 700/o (and the planned future urban area) are located along the flood plain of the river and the coastal plain fronting the Malacca Strait. The predominate geology of these plains is marine clay with the watertable generally at a depth of one metre.

THE STUDY The existing means for disposal of sewage are inadequate causing pollution of the urban stormwater drainage system and the receiving waters to which the system discharges. Intestinal disease is common and more serious epidemics have occurred from time to time in the past.

The existing urban drainage sytem has many deficiencies that cause flooding within the urban area. The lower reaches of the Malacca River are the outlet for discharge from both the urban drainage system, urban runoff, and the river's 600 sq. km catchment, rural runoff. On three occasions during the past 35 years, the last in January 1971, the rural runoff has caused substantial inundation of the flood plain of the river with the maximum depth and duration of the inundation increasing on each occasion . Urban development within the catchment and on to the flood plain itself continues to increase the urban runoff and the frequency and effect of inundation.

With this background the Economic Planning Unit of the Prime Minister's Department, Malaysia, in 1981 commissioned Angkasa-GHD to carry out a feasibility study, prepare a Master Plan, develop technical standards and specifications and the preliminary engineering designs for the sewerage of Malacca and 44

WATER March, 1986

J. A. Crockett T. J. Fricke The four authors are with the consulting organisation, Gutteridge Haskins and Davey PIL and are located in the Melbourne office of the company.

JOHNATHON CROCKET is a B.E.(Hons.) Chem ical and Master of Engineering Science, University of Melbourne (1973). He is the Principal Chemical Engineer with GHD and is responsible for investigation, process design, commissioning and operating advice for municipal and industrial water and sewage treatment plants throughout Australia and overseas.

TOM FRICKE graduated in Civil Engineering with honours from the University of Tasmania (1967) and pursued post-graduate studies at the University of NSW. With GHD he is Principal in Charge of the Hydrology / Hydraulics the development of an urban drainage scheme .

DEMOGRAPHIC PROJECTIONS The demographic projections of the study were based on the preliminary figures from the 1980 census. The projections to the year 2010 and the design (ultimate) population are: • 1990 - 290 000 persons • 2000 - 380 000 persons • 2010 - 460 000 persons • design - 770 000 persons

MASTER PLAN SEWERAGE Existing Conditions

Malacca has no municipal waterborne sewerage scheme. Within the urban areas about 900/o of the water closets discharge to septic tanks which, in general, are of inadequate capacity and, with few exceptions, discharge directly to the urban drainage system. The discharge from the balance of the water closets is conveyed by sewage collection systems to Imhoff tanks discharging directly to the urban drainage system as do all other sanitary plumbing fixtures.

A preliminary survey during the study included gauging and analysis of the more significant flows of industrial sewage

J.B. Murray

R.H. Smith

Division and is co-author of 'Malaysian Urban Drainage Design Standards and Procedures '. He is also Deputy Chairman of the Review Panel for revision of 'Australian Rainfall and Run-off'.

JOHN MURRAY is a Civil Graduate, University of NSW (1952). With GHD he is Principal Engineer Sewerage and Water Supply and in recent years has been responsible for the determination of design parameters and layout of the extensive sewage collection system for the bayside development of the Mornington Penninsula. He was Project Manager for the Malacca Study.

ROSS SMITH grad.uated B.E. Civil from the University of Melbourne (1965) and is Senior Design Engineer Sewerage with GHD responsible for the detailed design, tender d~cuments and tender appraisal for sewage collection systems. discharging directly to the drainage system. It was estimated that on the basis of organic load these discharges are equivalent to about 15 per cent of the total sewage discharge.

The combined domestic and industrial sewage exerts a significant pollutant load on the receiving waters of the rivers and creeks passing through the urban areas and on the coastal beaches and waters of the Malacca Strait into which they flow.

A tidal barrier located seven km from the mouth of the Malacca River permits substantial uptream diversions for irrigation. During the generally drier months of December, January and February when monthly rainfalls of less than 30 mm can occur, the diversions can equal the river flow . At these times all or part of the river downstream of the tidal barrier is likely to contain zero dissolved oxygen, be septic and black and emit offensive odours primarily due to hydrogen sulphide. The study concluded that for the existing conditions a minimum river flow past the tidal barrier of 260 ML/day or about a third of the river's average daily flow is required to prevent the above conditions. It was further concluded that this minimum river flow could be reduced to 70 ML/day following the provision of sewerage faci lities to about 75 000 equivalent persons (ep) under Phase One of the sewerage scheme.

- overall (3 cells) - 315 kg BOD/ ha .ct • overall detention, 9 days minimum • lagoon sides faced with stone rubble at slopes of 0.7:1 • multiple inlets to aid distribution with provision for possible recirculation to the inlets of oxygen-rich algae content effluent from the tertiary lagoon.

TABLE 1. EXISTING AND POTENTIAL USES OF WATERS IN THE STUDY AREA Existing Uses

Potential Uses

Existing Uses to be A bandoned or Discouraged

Malacca Ri ver mouth to Peringgit

Navigation, Drainage, Liquid & Solid Waste Disposal, Oil Disposal, Water fo r Processing & Cooling, Collection of Shellfish, Swimming

Aesthetic Appreciation, Recreational Boating

Solid Waste Disposal Collection of Shell fish Swimming, Oil Disposal

Malacca River Peringgit to Tidal Barrier

Drainage, Liquid & Solid Waste Disposal, Water for P rocessing & Cooling

Aesthetic Appreciation , Rec. Boating

Solid Waste Disposal Swimming

Malacca River abo ve the Tidal Barrier

Drainage , Irrigation, Stock Watering Water Supply, Fishing, Fish Farming, Swimming, Recreational Boating, Liquid & Solid Waste Disposal, Aesthetic Appriciation

Putat Ri ver

Drainage, Irrigation, Stock Watering, Liquid Waste Disposal

China Drain & Seri Malacca R

Drainage, Irrigation, Stock Watering, Liquid & Solid Waste Disposal

Solid Waste Disposal

Lereh and Duyong Rivers

Drainage , Irrigation , Stock Watering Liquid & Solid Waste Disposal, Fishing, Fish Farming, Aesthetic Appreciation

Solid Waste Disposal Fishing and Fish Farming

Malacca Strait to 3 km from mouth of Malacca River

Aesthetic Appreciation , Liquid & Solid Waste Disposal , Navigation

Malacca Strait more than 3 km from mouth of Malacca Ri ver

Aesthetic Apprication , Fishing, Liquid & Solid Waste Disposal , Navigation, Swimming, Recreational Boating

Zone

Receiving Waters

The receiving waters of the study area were divided into eight zones . Table I shows potential uses within each zone together with existing uses including swimming, collection of shellfish and the disposal of solid wastes and oils which is to be abandoned or discouraged in some or all of the zones.

The study determined quality standards for the receiving waters for 11 beneficial uses including water supply, industrial water (cooling etc.), swimming, stock watering, collection of shellfish, recreational boating and irrigation . These quality standards were of major significance in selection of the preferred treatment processes for the initial and subsequent stages of the sewage treatment plants.

Public health considerations emphasise the need for efficient disinfection of effluent from the treatment plants to ensure effective removal of pathogenic bacteria, virus, ova and cysts . Ten treatment processes that included anaerobic lagoons, facultative lagoon , aerated basins and facultative lagoons, and activated sludge with chlorination were reviewed. It was concluded that three cell facultative lagoons were preferred, on economic and practical operation grounds, for sites where there was sufficient suitable land available and an effluent quality averaging 50 mg/ L BOD and 100 mg/ L SS without nitrification was compatible with the target water quality for the receiving waters.

A review of alternative types of sewage collection systems concluded that the preferred alternative was a conventional separate system comprising gravity sewers in conjunction with~ ump stations and rising mains. Higher areal flows permitted adoption of relatively flat graded sewers to minimise depths in areas of high groundwater table .

Components of dry and wet weather flows were reviewed and new design flow criteria developed based upon GHD 's Australian experience wi th flexible systems in tropical areas . Typical maximum hourly dry and wet weather flows for catchments with a design density of development of 210 ep/ ha are shown in Figure I. The adopted design criteria for the components of the sewage collection system to minimise hydrogen sulphide generation included minimum velocities of: • gravity sewers - 0. 75 m/ sec when flowing full; • rising mains - 1.20 m/ sec for at least one hour per day.

Despite this, appropriate materials of construction, design techniques and some sulphide control techniques will be necessary, P/ rticularly during the early years of operation, to prevent significant corrosion and objectionable odours.

Solid Waste Disposal Swimming

Solid Waste Disposal

Recreational Boating

Solid Waste Disposal

After an extended review of plants previously developed by GHD in tropical regions and existing Malaysian plants the design parameters adopted for the facultative lagoons differ significantly from those commonly adopted in the temperate zone of Australia . These parameters include: • BOD loading (minimum mean monthly air temperatures at Malacca 26°C) - primary lagoon - 600 kg BOD/ ha.ct

Sewerage Strategies and Their Evaluation

Preliminary designs were prepared and evaluated for four alternative collection and treatment concepts. The estimated

13 00

r-,,.....,_ -c:,

"' ~

'-........

0...

w ...._ _J

Sewage Treatment

Sewage Collection System

1000

........

"

' riv(: '-t.vf: ,

.........

,o

I

I

"!_,ljf:,9

I"-, r-,.

1

......,9..,,,/;Jt

~v -

'"""l"-,f:°/4/ ~

r--., -....:: ltf:,9 ;::-

~...__ r--

~y

r-,-....__ ........... r--,...

5 00 1000

5000 10,000 POPULATION - E.P. MA XIMUM HOURLY FLOW FOR 2 10 E.P./h a

50,000

Figure 1. Maximum hourly sewage flow WATER March, 1986 45

TABLE 2. ESTIMATED COMPARATIVE COSTS OF ALTERNATIVE LAYOUTS No. of Plants

1•

Comparative Costs-Million $(A) /98/ Capital

A nnual

90

12 16 16 19

120 110 125

LEGEND

INSERT

.

,.

,,,,,,, S tudy Area BoUldary O

,ui_~

Ma1or Pump Sw oons

- - Trunk Sewer s & Rising Mains

.

___-:. .,..•.,.~

#~~~

~ Sewerage Treatment Plaits

-- ··"~f-'--'-----

l<·.;).j Phase One

D

Phase Two

}

by ye,"r " 2000

Im Phuse Three

• Alternative si te included at th e reques t of Stat e Govern ment.

t:::J Al1er2000

comparative costs, excluding reticulation works common to each alternative are summarised in Table 2.

The concept shown in Figure 2 containing five treatment plants was preferred because of: • lowest capital and annual costs; • most compatible to stage development; • reduced environmental impact of eff)uent from smaller plants and hence possible deferment of need to upgrade effluent quality; • reduced detention times and higher ratios of early to design flows within the collection system will minimise the generation of hydrogen sulphide.

The catchments of the five treatment plants were divided into 36 subcatchments and a weighting system used for evaluation and to determine a priority rating for each based upon: • projected populations; • proportion of the projected year 2000 population; • discharges of industrial sewage; • receiving waters; • economic factors.

The bases for inclusion of subcatchments in the first three phases of the collection system, programmed for completion by the year 2000, were the priority rating, geographical location to subcatchments of similar priority rating, catchments of existing and future treatment plants and sewered areas and finally the limit of available finance for capital works. The projected sewered populations and estimated capital costs (1981) by the year 2000 for the sewage collection system are 310 000 ep and A$125 million.

The adopted strategies for the stage development of the treatment plants have adequate flexibility to allow for variations in the rate of connection of populations, per capita flows and loads and quality of effluent, to comply with the target quality standards for receiving waters. The proposed treatment processes are: • two plants with design populations of 185 000 and 150 000 ep discharging to the Malacca River Stage 1 - facultative lagoons Stage 2 - aerated basins followed by facultative lagoons Stage 3 - activated sludge with either maturation lagoons or chlorination • three plants with design populations of 175 000, 185 000 and 60 000 ep which do not discharge to the Malacca River - facultative lagoons .

The estimated capital cost (1981) by the year 2000 for the treatment plants is A$15 million.

Financial Analysis

Financing, revenue and pricing policies 46

WATER March, 1986

Q'c

Malacca Strait

- --

0

K1lome1 res

1

1

Figure 2. Sewerage, phase development

were reviewed . Prime objective of the financing policy is parity of cost to users receiving similar services from either existing or new sewerage schemes while at the same time ensuring that these costs do not impose an intolerable financial burden and hence hardship on a signficant portion of the community. With few exceptions the policies for new schemes, particularly during the period of major capital works, must include government assistance if these goals are to be attained.

The capital cost for the Malacca scheme will be high when compared with costs for other schemes with catchments more compatible to construction of sewerage schemes . The higher cost is due to the predominantly flat topography and difficult geology and within the old town, street widths of less than eight metres, and streetscapes that date from the 17th and 18th centuries. Hence the particular need of this scheme for government financial assistance.

The proposed pricing policy recognises that for communities with socio-economic status and climatic conditions similar to those within the area of the Malacca Master Plan there is a direct relation between water consumption and sewage discharge. The elements of the policy are: (1) charges broadly relating to ability to pay rather than the service provided; (2) a charge directly relating to the service provided.

These charges area: (!) A Sewerage Improvement Rate, levied on unsewered properties within the phase under construction; and A Sewerage Rate, levied on sewered properties.

These rates would be a percentage of the improved property valuations with set minimums and payable every six months.

(2) A Water Meter Surcharge, levied on properties connected to the scheme. The payment would be calculated as a percentage of the metered water consumption

with a set minimum, and payable monthly.

The proposed policies will result in annual payments by users that are generally within the range of 2 to 40Jo of the estimated average annual household income and so satisfying a frequently adopted criterion for ability of users to pay.

Organisation Structure

Forms of organisation structure considered for the implementation, construction, operation and maintenance of the work proposed in the Master Plan were: • expansion of the Engineering Department of the City Council; • Water Board ' s responsibilities extended to include the sewerage works while the City Council would continue its responsibilities for urban drainage; • new river basin authority with responsibilities for all water supply , sewerage and urban and rural drainage works.

The preferred structure is for the establishment of the Sewerage and Drainage Section within the Engineering Department of the City Council. It will be some years before the new Section is fully staffed with experienced personnel and during this period appropriate personnel from the Consultant's staff will be seconded to assist with the implementation of the initial works and the necessary technolology transfer to the senior officers of the Section.

MASTER PLAN URBAN DRAINAGE

• increased urban discharges arising from upstream urban development • ad hoc land fillin g preventing effective drainage of adjacent infilled areas.

Tides play a significant role in the behaviour of the river and drainage sysem and the consequent extents of flooding.

Almost all major trunk drains are subject to tidal influence with a consequent effect not only on flow capacity, but also on any self-cleansing ability that the drains might have. Sea level can rise as high as RL 1.8 m, i.e. above some natural surface levels .

Design Criteria

In order to systematically assess and quantify the inadequacies in the existing drainage system , certain design criteria were adopted at the outset.

The secondary (5 to 25 ha catchment area) and trunk (greater than 25 ha area) drains were to be sized for the discharge from the 'initial' (2-5 year return period) storm and trunk drains checked to ensure that the discharge from the 'major' (100 year return period) storm does not cause significant inconvenience.

The Rational Method of flood estimation was adopted for estimation of peak runoff from all catchments less than 50 sq km in area. Rainfall intensities ranged from 150-225 mm / hr for 10 minute duration storms to 65-110 mm / hr for 60 min storms. The runoff coefficients adopted for the different types of land use are set out in Table 3.

TABLE 3. ADOPTED RUNOFF COEFFICIENTS Land Use

Runoff Coefficients

• Commercial • Industrial • Residential: -low density • kampung medium density • bungalows and semi-detached houses • terrace , link high density and shophouses very high density• multi-storey • Institutions • schools, airports etc • parks • Open Space • Jungle • Rubber • Padi

0.90 0.80

Study Area

The principal topographical features of the 5000 ha Study Area are the flood plain of the Malacca River (1375 ha), the 1120 ha coastal plain fronting the Malacca Strait and a number of isolated hills rising to about 100 metres above sea level. The plains have ground slopes of the order of 0.1 OJo and are intersected by two main rivers, the Malacca and the Putat, and several minor streams. The Malacca and Putat Rivers have a combined -predominantly rural - catchment area of 600 sq km and are the principal trunk drains for more than 500Jo of the Study Area.

The Study Area is subject to two types of flooding: • rural floods due to medium intensity long duration (several days) storms over the catchment that in turn cause long duration inundation • urban floods due to high intensity short duration (several hours) storms.

The nature of 'urban' flooding is not well documented, partly because it occurs so frequently that systematic recording would result in a huge compendium of data. Suffice to say that even in the short (12 month) period of the Study numerous examples of flooding in urban areas occurred resulting from deficiencies in the existing drainage system such as: • inadequate capacity of drains and culverts • blockage due to rubbish dumping and / or poor maintenance

0.55

0. 70

0.85 0.90 0.5 to 0.80 0.30 0.35 0.45 0.10

The existing drains within both the urban and undeveloped areas are generally either lined open channels with vertical sides, lined with side slopes of about 1: 1 or unlined with slide slopes of about 2: 1.

Because of space limitations throughout most of the existing urban areas, future (and upgraded existing) drains were generally assummed to be fully lined with vertical sides, with the 'major' storm discharge confined where possible to the drainage reserve . In partially developed areas, where space permitted, the drains were assumed to be lined only for the 'initial' storm discharge. For trunk drains in such areas the sides would be extended in unlined form to carry the 'major' storm.

All unlined drains were to have a lined low flow invert of capacity equal to 30Jo of

the major storm discharge and a minimum velocity where practical of 0.5 m/ sec. Tide levels in backwater calculations were assumed to be RL 0.85 m for secondary drains and up to RL 1.20 m for trunk drains .

Existing Urban Drainage System

Th~ existing urban drainage system was subdivided into seven catchment groups containing some 104 catchments. Land uses for the groups range from fully urban to' rural/urban and predominantly rural.

In order to analyse the ability of the existing system to cope with runoff from existing development it was necessary to document the current land use. Because of much recent rapid urban development in the Study Area, official records were 10 years out of date and a considerable amount of file research and field inspection was carried out so as to adequately define land use for all catchments. The following categories were used - residential , commercial, industrial, institutions and government reserves, kampung (village), open space, padi (rice), rubber and jungle.

The 104 catchments were further subdivided into 200 sub-areas based on locations of drain junctions, culverts, bridges and changes of drain cross-section, grade and/ or material of construction . The hydrological criteria were then applied to determine the existing design discharges at the downstream limits of each sub-area for both the initial and major storms. The calculations were repeated for future land use conditions based on the urban structure plan. 1In order to assess the hydraulic capacity of the existing drains, an extensive survey (seven parity months) was carried out to record the longitudinal section and cross section of all drains . The survey involved some 500 cross sections along about 60 km of trunk and secondary drains. Hydraulic slope-area and backwater analysis was then applied to each drain section fo determine existing discharge capacities.

The existing capacities were then compared with the initial storm discharges for both existing and future land use so as to quantify the deficiencies in the existing drainage network. A priority rating system was especially developed for the study to rank the drains requiring upgrading in order of need. The system took into account urgency, drain deficiency, culvert deficiency and disruption factors to arrive at an overall priority. In total some 660Jo of the 57 km of existing drains and 740Jo of the 162 culverts are inadequate to cope with runoff from existing land use conditions .

Lower Reaches of Malacca River

The lower reaches of the Malacca River are of considerable significance to the urban drainage system because they determine the tailwater levels at the discharge points of many trunk drains and the river is itself the major trunk drain for a large section of the Study Area.

Calculations were carried out to estimate the likely future urban and rual WATER March, 1986 47

flood discharges to the river to enable comp~rison with the river 's existing capacity of some 55 cumecs. ' Urban' discharges of 125 to 140 cumecs were estimated and rural peaks of 170 to 240 cui:necs. The lower reaches are completely ?mlt up and t~ere is little opportunity to increase capacity . Thus a diversion comm en cin g up stre a m o f th e clo se ly deve!ope~ ~rea at location P on Figure 2 was identified for fu rther investigation . It was considered that this was essential fo r development of an effective urb an drainage system and to minimise interfe rence to the operation of the sewage collection system .

The diversion option was assessed as requiring a capacity of 105 cumecs and a number of alternative routes between points P and Q on Figure 2 were investigated. The available gradient over the 3 km length was only 1 in 3000. A total (eserve o f ~5 km was found to be required incorporating an unlined trapezoidal section o f base width 8 m , top width 43 m and depth 6 m . Including land acquisition the estimated capital cost of the diversion ranged fr om A$8-1 2 million, depending on the route selected .

Master Plan U rban Drainage For all drai ns defi cient for fu ture land use conditions, backwater analyses o f altern ative cross sections were carried out until a config uration was arrived at that ensured the initial storm design water surface profile fell below the level of future development.

T he study concluded with the collation of all infor mation relating to criteria ~apa~ities, deficiencies and strategies to identify the drainage priorities constituting th e urban drainage master plan .

T he recommended p lan consists of the fo llowing components:

Structural Measures: •

major river flood diversion scheme ' estimated cost A$ 12 million • major drai nage upgrading works • 66 km o f drains • 92 culverts • A$35 million capital cost • minor drai nage works • 5 km of drains • 4 culverts • A$2 million capital cost

No n-structural M easures: •

p rohibition of development in the active river channel (floodway) and active drainage fl ow paths

• deta iled hydrolo! ic and h ydrauli c fl ood study o f Malacca River to determine floo d hydrographs and profiles fo r a range of design storms to enable adoption of designated flood levels for planning and building control purposes.

• location of futur e urban development only on ground either already fill ed to or above flood level ' • c?nt ro l o f indu strial was tewa te r ?ischarges to drainage system prior to impl7~ e_ntation of sewerage scheme • proh_ibition of development in reserves r~quir_ed fo r both the Malacca River div7rsion and for the recommended drainage works.

The wo rks recommended for implementation by the year 2000 were: P hase I 6.4 km of drains, 15 culverts, A$ 10 million Phase II 9.4 km of drains, 22 culverts A$7 million ' Phase III 11.6 km of drains, 21 culverts A$6 million ' In order to implement the programme it was . reco!11mended that the City Council Engineenng Department 's resources and responsi bilities be expanded to include constructi~n,_ replacement and operation o f the existing and proposed drainage works within th e Study Area .

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PEOPLE AND APPOINTMENTS QUEENSLAND

LONG SERVING BOARD MEMBER RESIGNS Ray Bange, the longest serving member of the Board of Examiners of Engineers and Overseers of Works to Local Authorities , resigned from the Board in November last. Formerly Head of the Department of Civil Engineering at the QIT, he has served on the Board since 1968.

One of Queensland 's best known Engine~rs he has played a key part in prof!)otin_g the practice of municipal engineering and also in developing courses for the training of technical and professional engineers.

At the QIT he was responsible for the introduction of the special local g?vernment subjects, post-graduate diploma courses in environmental and municipal engineering 1 the associate diploma courses an d the ' promotion of workshops and publications.

At the Board level Ray contributed materially to the upgrading of overseas qualification requirements establishment of the TAFE cor'. respondence course and numerous other aspects of the municipal scene. l_n recent months he has been appointed to head the office of Q Search at QIT where, as Director he is respon sible for research and development programmes, commercial and con sultancy services , continuing education and technology transfer for the whole Institute.

48

WATER March, 1986

LOCAL GOVERNMENT ENGINEER ASSOCIATION

NEW PRESIDENT BOB SEIFFERT Bob Seiffert , Manager - Technical Services/Shire Engineer of the Shire of Cobram , was recently elected as the 1986/87 President of the Local Government Engineers Association of Victoria which represents more than 340 Municipal Engineers Deputy Mun_ i cipal Engineers, and other protess1onal engineering staff employed in Local Government in Victoria.

T_ he Association provides technical advice to government departments statutory authorities and any other in '. terested parties and is represented on a large number of government sponsored committees and task forces .

The Association also plays a significant role in the staging of Civ En Ex which is an annual , multi-million dollar exposition of earthmoving plant, equipment and material. Funds gen~rated by Civ En Ex are used to pro~1de Research Fellowships to engineers who study an approved a~pect of local government world wide .

A~ter gualifying as a Municipai Engineer In 1972, Mr Seiffert has held the position of Shire Engineer with the Shires of Rylstone (NSW) and Cobram, the latter since 1975. At 38-y~~rs . of ~ge, he possesses qual1f1cat1ons in ~i_vil Engineering, Ma_na_g ement, Mun1c1pal Engineering , Buil~ing ~urveying and Water Supply Engineering .

Mr Seiffert is married with three daughters and is ei:ctremely active in community affairs. He has been a ~em~er of the Association 's Execu tive since 1981 .

Other nofable members of the Association 's Executive include Brian O'Donnell of Richmond City (Vice President - City) and Gary Surman of Buln Buln Shire (Vice President Rural).

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SINCLAIR KNIGHT AND PARTNERS

NEW DIRECTOR APPOINTED Sinclair Knight and Partners Con su~ting Engineers announce the apP<;Jlntment of Mr Fred Randall as a Director of the Company.

Before his appointment as Direc t~r, Mr Randall was an Associate Director_of the Company, and was r~sponsIble for supervision and direction .of ~ater ~up~ly and sewerage stu~1es , 1n~est1gat1ons, and project design and implementation . . Mr Ran~all has 18 years experience in Australia and th e United Kingdom in the field_s of sewerage, water supply and draina~e investigation , design and construction supe rvision and in admin istration .