IMIESA March 2019

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IMESA The official magazine of the Institute of Municipal Engineering of Southern Africa

infrastructure development • Maintenance • service delivery

Municipal INSIGHT Harnessing the benefits of O&M Hanré Blignaut Deputy Director: Engineering Planning, Overstrand Municipality

Water metering technology

Smart versus mechanical

Mariswe

Engineering infrastructure solutions

Municipal Focus: Western Cape

Sustainable sludge management ISSN 0257 1978

Environmental engineering

Safe travel on Sani Pass

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9 0 0 1

volume 44 no. 3 March 2019 www.infrastructurene.ws

IMESA

INSIDE

The official magazine of the Institute of Municipal Engineering of Southern Africa

INFRASTRUCTURE DEVELOPMENT • MAINTENANCE • SERVICE DELIVERY

MUNICIPAL INSIGHT

Mariswe

Harnessing the benefits of O&M Hanré Blignaut

Engineering infrastructure solutions

Deputy Director: Engineering Planning, Overstrand Municipality

11 Water Metering Technology

Smart versus mechanical

Municipal Focus: Western Cape

Sustainable sludge management ISSN 0257 1978

Meters, Pipes, Pumps & Valves

Environmental Engineering

Safe travel on Sani Pass

Regulars Editor’s comment

3

President’s comment

5

Index to advertisers

56

6

What to expect from Mariswe

8

Harnessing the benefits of O&M

Municipal Focus | Western Cape

Meters, Pipes, Pumps & Valves With or without annulus

30

SupremeServ brings solid aftermarket services

31

Regular pipeline inspections are critical

32

With or without annulus

33

Doing more with less

34

Tapping into the Klein Karoo

11

Drought relief for Beaufort West

13

Beyond durability with Flowtite GRP 15 The future of sustainable sludge management Trenchless innovations for Cape Town

Design review using VR

Poor waste planning and health

40

Safe travel on Sani Pass

41

Insurance Engineering and construction insurance in a challenging market

43

Cement & Concrete Crafting footpaths in sand and mortar

44

18

Precast as a vocation

47

23

Transport, Logistics, Vehicles & Equipment

Water & Wastewater

Technology driven

49

e-Power evolution

50 52

Rethinking filtration

25

Power and efficiency

Improving safety through odour control

26

Building Materials

Innovative aeration control

27

Cutting carbon emissions

41

36

16

World Water Day Leaving no one behind

Virtual Reality

Environmental Engineering

Municipal Insight

33

28

APE Pumps adds submersible series

Waste Management

Cover Story

Overstrand Municipality has awarded a 15-year operations and maintenance contract to Veolia Water Technologies South Africa to manage the municipality’s extensive water and wastewater infrastructure network. P8

Smart versus mechanical

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Mariswe’s stated aim is to engineer infrastructural solutions that build communities and improve people’s lives. P6

INDUSTRY INSIGHT

Municipal Focus | Western Cape Tapping into the Klein Karoo

ENVIRONMENTAL ENGINEERING Safe travel on Sani Pass

44

54

Cement & Concrete Crafting footpaths in sand and mortar

EDITOR’S COMMENT

Water and wastewater economics

G

MANAGING EDITOR Alastair Currie SENIOR JOURNALIST Danielle Petterson JOURNALIST Liesl Frankson Head OF DESIGN Beren Bauermeister Chief SUB-EDITOR Tristan Snijders ContributorS Luchelle Damons, Randeer Kasserchun, Annejan Visser OPERATIONS & PRODUCTION MANAGER Antois-Leigh Botma Production COORDINATOR Jacqueline Modise financial MANAGER Andrew Lobban DISTRIBUTION MANAGER Nomsa Masina Distribution coordinator Asha Pursotham SUBSCRIPTIONS subs@3smedia.co.za Printers Paarl Media KZN +27 (0)31 714 4700 ___________________________________________________

roundwater is an excellent backup solution for towns and cities faced with depleted dam storage capacities – in some cases, especially in arid and drought-prone regions, it’s currently the only source of water.

The Table Mountain Aquifer project is a classic example of how an abundant underground and natural reservoir could support water shortages in the City of Cape Town if its dams reach critical sub-supply levels.

That’s still a contingency plan for now, though, but for other municipalities, it’s an immediate priority. In this issue, we report on how the Karoo towns of Beaufort West and Oudtshoorn are utilising groundwater via borehole wellfields as a present-day mitigation factor.

Semi-desert regions like the Karoo will always be the worst exposed; however, across the board, climate change is making it much harder to predict future outcomes based on past data. Major metros like Cape Town, Durban, Johannesburg and Port Elizabeth can only build so much storage capacity within their catchment zones. On top of this, the intensive rate of urbanisation poses major risks to medium- and longer-term security for city planners, if current usage patterns don’t change.

South Africans currently exceed the world average when it comes to daily consumption. Ours is around 237 litres compared to the world daily average of approximately 173 litres.

Advertising Sales Jenny Miller Tel: +27 (0)11 467 6223 Email: jennymiller@lantic.net ___________________________________________________

A division of Novus Holdings

Publisher Jacques Breytenbach Paarl Media (Pty) Ltd t/a 3S Media 46 Milkyway Avenue, Frankenwald, 2090 PO Box 92026, Norwood 2117 Tel: +27 (0)11 233 2600 Fax: +27 (0)11 234 7274/5 www.3smedia.co.za Annual subscription: R600.00 (INCL VAT) ISSN 0257 1978 IMIESA, Inst.MUNIC. ENG. S. AFR. © Copyright 2019. All rights reserved. ___________________________________________________ IMESA CONTACTS HEAD OFFICE: Manager: Ingrid Botton P.O. Box 2190, Westville, 3630 Tel: +27 (0)31 266 3263 Fax: +27 (0)31 266 5094 Email: admin@imesa.org.za Website: www.imesa.org.za BORDER Secretary: Celeste Vosloo Tel: +27 (0)43 705 2433 Fax: +27 (0)43 743 5266 Email: celestev@buffalocity.gov.za

Financial implications It’s both a water management issue and a financial one: over-use puts pressure on scarce resources, while non-payment for services, where it exists, places major strain on utilities and municipalities to fund and deliver. Tariffs from electricity and water represent the bulk of revenue inflows that municipalities are expected to use to run and maintain infrastructure.

That’s alongside funding from the Department of Water and Sanitation (DWS) for bulk services like dam, treatment works and pipeline infrastructure.

At present, the DWS has a significant backlog of unfinished projects. These include dam wall raising operations at Hazelmere, Tzaneen and Clanwilliam.

Various proposals are being put forward to clear disputes and get these projects back online.

Meanwhile, some 106 Regional Bulk Infrastructure Grant projects remain uncompleted. These include the

EASTERN CAPE Secretary: Susan Canestra Tel: +27 (0)41 585 4142 ext. 7 Fax: +27 (0)41 585 1066 Email: imesaec@imesa.org.za KWAZULU-NATAL Secretary: Ingrid Botton Tel: +27 (0)31 266 3263 Fax:+27 (0)31 266 5094 Email: imesakzn@imesa.org.za NORTHERN PROVINCES Secretary: Rona Fourie Tel: +27 (0)82 742 6364 Fax: +27 (0)86 634 5644 Email: np@imesa.org.za SOUTHERN CAPE KAROO Secretary: Henrietta Olivier Tel: +27 (0)79 390 7536 Fax: +27 (0)86 629 7490 Email: imesasck@imesa.org.za WESTERN CAPE Secretary: Michelle Ackerman Tel: +27 (0)21 444 7114 Email: imesawc@imesa.org.za FREE STATE & NORTHERN CAPE Secretary: Wilma Van Der Walt Tel: +27 (0)83 457 4362 Fax: +27 (0)86 628 0468 Email: imesafsnc@imesa.org.za

Municipal debt According to the latest Financial Census of Municipalities report released by Statistics SA, total municipal debt amounted to R225.8 billion in 2016/17. Two-thirds, or R142.2 billion, was accrued

by South Africa’s eight metros.

The report states, “Debt owed to creditors, which include registered suppliers and service providers such as Eskom and the water boards, contributed 43% to total municipal debt in 2016/17.” That’s a considerable amount, which has to impact on how municipalities execute their maintenance and upgrade targets, compounded by ensuing year-on-year reductions in infrastructure grant inflows.

Interestingly, improvements in consumer revenue collection showed a marked improvement for services like water, electricity and wastewater for Q2 (October to December) during FY 2018/19. This is according to National Treasury’s latest local government revenue and expenditure report. However, aggregate municipal consumer debts amounted to R184.7 billion, of which 73.8% (R136.3 billion) was owned by households.

Alongside education drives like the DWS’s National Water Week in March, smart technologies must be part of future demand management. The deployment of intelligent meters will ensure that everyone receives an equitable share, and that users pay for services. These meters will also cut off users who exceed their quotas during severe drought conditions.

Alastair To our avid readers, check out what we are talking about on our website, Facebook page or follow us on Twitter and have your say.

struc www.infra

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mechanical

• SERVICE

Mariswe ring

: Municipal Focus Western Cape ement

Sustainable

sludge manag

7 1978 ISSN 025

Infrastructure News

DELIVER Y

infrastructur

Engineerin Deputy Director: Municipality Overstrand

ring Water Mete Technology

• MAINTE NANCE

Enginee e solutions

of O&M the benefits Harness ing t g Planning, Hanré Blignau

Smart versus

@infrastructure4

IMESA

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INFRAST RUCTUR

All material herein IMIESA is copyright protected and may not be reproduced either in whole or in part without the prior written permission of the publisher. The views of the authors do not necessarily reflect those of the Institute of Municipal Engineering of Southern Africa or the publishers.

Sebokeng Wastewater Treatment Works (WWTW) in Gauteng, the Ratlou and Madibeng Bulk Water Supply schemes in the North West, and the Stellenbosch WWTW in the Western Cape. According to the DWS, various solutions are being investigated. A DWS statement says, “These include municipalities availing co-funding in the next financial year.”

Environmental EngineeringSani Pass Safe travel on

n c l . VAT ) R50.00 (i 2019 • • March 4 No. 3 Vo l u m e 4

Cover opportunity

In each issue, IMIESA offers advertisers the opportunity to get to the front of the line by placing a company, product or service on the front cover of the journal. Buying this position will afford the advertiser the cover story and maximum exposure. For more information on cover bookings, contact Jenny Miller on +27 (0)11 467 6223.

IMIESA March 2019

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President’s comment

IMESA

The reality of the 2019 budget As municipal engineers, we don’t create the budgets, but we certainly work hard to motivate for them. After that, it’s our job to ensure their implementation in the most efficient way possible.

T

hat means ensuring that designs are fit for purpose and that construction materials and processes are optimal. However, past reports from the Auditor General’s office show that inefficiencies and wastage at municipalities have been deepening trends over the past few years. There are extenuating factors. A key one is the prevailing nonpayment culture, which severely hampers the ability to budget, plan and deliver essential services.

To a large degree, municipalities need to be financially self-sufficient and are responsible for facilitating micro- and macroeconomic development within their regions – with infrastructure maintenance and new works being at the core of their town and city planning.

Money is tight; tax revenues are shrinking.

However, despite this, public record shows that billions, which could have been spent annually on deserving projects, have been misappropriated, misspent, or simply rolled over to a future financial year. As municipal engineers, we need to be part of the change that brings things back on track.

The 2019 budget speech delivered by Minister of Finance Tito Mboweni focuses strongly on regrouping, rebuilding and refocusing NDP and related goals. Among the core strategies is the need to boost GDP, reduce public debt, improve tax collection, and reconfigure SOEs.

No quick fixes As Mboweni stated, “It will not be easy. There are no quick fixes. But our nation is ready for renewal. We are ready to plant the seeds of our future.”

At this stage, government’s proposed Infrastructure Fund is a work in progress, but the pipeline of potential projects looks promising, particularly if there’s a positive appetite from the private sector for co-funded initiatives. One area that could see strong public-private partnership growth is in the renewable energy field. Other potential sectors include water and wastewater treatment works, and toll roads.

In terms of infrastructure spend, one of the budget highlights is the allocation of some R30 billion to maintain and build new schools.

An additional R2.8 billion has also been added to the School Infrastructure Backlogs Grant to replace pit latrines at over 2 400 schools.

Another encouraging note is the commitment to invest in the upgrading of informal settlements, which pose a major challenge for municipalities. The budget establishes a R14.7 billion pipeline to achieve this.

After a marked hiatus in roads spending, the construction sector has been hard pressed to survive. Hopefully, this picture will change soon. In the meantime, Sanral has been allocated an additional R3.5 billion, over the next three years, to improve non-toll roads.

As one of the budget’s central pillars, the successful roll-out of the Infrastructure

Fund is critical for the achievement of South Africa’s socio-economic objectives.

However, its success depends on crowding in investment flows from private sector and development finance institutions. If that works, then the plan is to accelerate R526 billion worth of on-budget projects.

That would certainly create a major boom for construction. If you add the R100 billion commitment from government over the next decade, the outlook could be very positive.

Randeer Kasserchun, president, IMESA

IMIESA March 2019

5

A 25 ML reservoir under construction in Kempton Park

What to expect from Mariswe Mariswe’s stated aim is to engineer infrastructural solutions that build communities to improve people’s lives.

A

new kid on the block?” you may ask. Not at all: rather a new name for a company that has matured and changed, and is no longer recognisable as the same company formed 47 years ago.

On 1 February 2019, UWP Consulting changed its name to Mariswe. The company remains true to its core business of consulting civil and structural engineering, driven by a desire to improve lives by providing sustainable engineering infrastructure solutions.

With sustainability in mind, Mariswe is positioned to provide services throughout the life cycle of infrastructure – from A structural steel sewer pipe bridge for a 900 mm diameter main outfall sewer constructed in Roma, Lusaka

planning, design and construction through to maintenance. “We are confident in our ability to successfully serve the total infrastructure life cycle, as we bring a great depth of knowledge, experience and client relationships to Mariswe,” says CEO Nonkululeko Sindane.

Companies change their names to announce that they are embarking on a journey of transformation. “For Mariswe, it was the other way around,” says Sindane.

“We’ve changed continuously in the past 47 years, but most significantly in the past decade.”

New owners UWP acquired three majority black-owned companies: Khula Africa Engineers in 2009, CME Consulting Engineers in 2012, and Sektor Consulting Engineers in 2018.

These acquisitions brought new technical expertise and projects to the company.

Most of the shares in the business have also changed hands. In 2016, UWP was 33% black-owned and 12% black-womenowned. A 25% stake of the black ownership was held by an external equity partner and 8% by black employees in management.

Nonkululeko Sindane, CEO, Mariswe

The remaining 67% was owned by white employees.

Today, Mariswe is 100% employee-owned and almost 56% black-owned. Black women effectively own 24% of the company. The equity partner’s 25% holding was bought

by Abaqeshwa, a company wholly owned by black employees in the business, while 31% of the shares are held by black managers and professionals within Mariswe.

These ownership changes are mirrored

by Mariswe’s board and management structures, with greater depth across service areas and regions. The company prides itself on the teamwork within and between its four self-sufficient regional operations, spread across eight offices in South Africa.

“Our presence across provinces means that we are particularly well placed to service national, provincial and, most importantly, municipal government, which continues to provide a steady flow of income for the company,” states Sindane.

BBBEE Level 1 She is delighted about Mariswe’s successful retention of its Level 1 BBBEE Contributor status in its first audit under the Amended Construction Sector Codes of Good Practice in November 2018. This achievement has a lot to do with Mariswe’s changing shareholding strategy, in which shareholders are becoming younger and more diverse in terms of race and gender, she explains.

Mariswe’s reputation as a company that upskills its employees through in-house mentoring and training is attracting motivated,

Cover Story Africa, Tanzania, United Kingdom, Zambia and Zimbabwe.

Water reuse PPP for City of uMhlathuze

A new 5 000 m3 stainless steel panel tank built to replace a leaking concrete reservoir in Lusaka

young employees. A new internal Leadership Development Programme was launched in 2019.

Sindane is particularly proud of Mariswe’s supplier development programme. “We have structured contracts in place for our supplier development programme; the support we provide is real and we hope to progress these relationships into meaningful partnerships.”

The company’s national initiative for teenage girls in their final years of school – entitled Nurture a Girl – is now in its third year, giving learners social support including mentorship and counselling.

Roots in Africa

But history has also played a role in Mariswe’s future, she points out. “Over 47 years, we have built a solid foundation. We have grown into a respected company with the depth of expertise to deliver projects of scale in our core technical disciplines of transportation, water and sanitation, structures, management services, and infrastructure planning.”

Mariswe’s experience across these core capabilities is proven by a strong portfolio of challenging projects. The largest assignment undertaken by the company is located in Lusaka, Zambia.

Lusaka water supply and sanitation project

When the Millennium Challenge Corporation, a US Federal Government-sponsored donor organisation, funded several large infrastructure construction packages in Lusaka, Mariswe was engaged to supervise six of the construction packages: • upgrading of Lusaka’s bulk water supply infrastructure, including the distribution network • construction of potable water storage infrastructure and reticulation networks in Name-change process high- and medium-density areas of Lusaka “The name change has taken two years (two projects) and we put our employees at the centre • construction of waterborne sewage of the journey by asking each office to infrastructure in high-density areas literally paint a picture of why they worked • upgrading and expansion of the sewage at UWP,” says Sindane. “Common themes treatment works at Kaunda Square emerged, providing the basis for a new set of • construction of 30 km of large, company values.” concrete-lined trapezoidal canals for stormwater management.

These are being undertaken The company has recently been appointed to undertake a study in Lesotho for the by six different international Ministry of Public Works and Transport contractors and the combined value of the construction works will exceed US$220 million (R3.1 billion) once completed in 2020.

Mariswe assembled a multinational, multi-disciplinary team of 70 people from the DRC, Ethiopia, Philippines, South More than 35% of Mariswe’s revenue is currently generated outside South Africa and successful subsidiary companies have been formed in Botswana, Ghana, Tanzania, Zambia and Zimbabwe. Projects have also been completed recently in the DRC, Lesotho, Liberia, Sierra Leone and Uganda.

A new branch of the South African business has recently opened in Lesotho.

Mariswe has been engaged by the City of uMhlathuze, incorporating the towns of Richards Bay and Empangeni, as lead consultant on the technical advisory team for the treatment and reuse of about 75 ML/ day of domestic and industrial wastewater through a public-private partnership.

Ghana OPRC To improve management of its road network, the Ghana Highway Authority appointed Mariswe to assess output and performancebased road contracts (OPRC) for the upgrading of 240 km of trunk routes and 800 km of feeder roads.

In performance-based contracting, the design and construction risks are transferred to the contracting entity, which is paid a lump sum to provide and maintain the road to specific standards.

Key aspects of Mariswe’s work are road network prioritisation, concept design and the preparation of draft bidding documents.

The company has recently been appointed to undertake a similar study in Lesotho for the Ministry of Public Works and Transport in a World Bank-funded project.

Water storage facilities Collaboration between Mariswe’s Structures and Water and Sanitation divisions has created an efficient one-stop shop for the design of urban reservoirs and water towers to meet growing requirements, resulting in appointments from both Johannesburg Water and the Ekurhuleni Metropolitan Municipality.

Following the design of a giant 5.5 ML water tower in Benoni in 2015, Mariswe has added another unique 1 ML water tower and three reservoirs to its portfolio in Gauteng.

These include the new 5 ML Benoni Central reservoir and 1 ML, 50 m high water tower; a new 25 ML reservoir in Kempton Park; and a new 22 ML reservoir in Woodmead, Johannesburg, which is still to be built.

www.mariswe.com

IMIESA March 2019

7

Hanré Blignaut, deputy director: Engineering Planning, Overstrand Municipality

Harnessing the benefits of O&M

Overstrand Municipality has awarded a 15-year operations and maintenance (O&M) contract to Veolia Water Solutions & Technologies South Africa to manage the municipality’s extensive water and wastewater infrastructure network.

O

verstrand Municipality has nine water and six wastewater treatment plants with a combined capacity of 59 Mℓ/day and 18 Mℓ/day, respectively.

These, together with the municipality’s five surface water sources, one river abstraction plant, 17 boreholes, three springs, 55 water and wastewater pump stations, 44 reservoirs, and 123 km of bulk water and wastewater pipelines must be managed and maintained on a daily basis.

AMBITIONS FOR

AFRICA

As of December 2018, Veolia is managing the day-to-day operations of this extensive network of infrastructure in what is the largest O&M contract of its kind in South Africa in terms of the equipment and number of facilities to be maintained.

With 15 different sites stretched over a distance of 250 km, Veolia has a difficult task to manage. A central management team has been established in Hermanus to manage and coordinate all aspects of operation, including the three maintenance teams that are available to assist and maintain the municipality’s infrastructure on a daily basis.

Why O&M? “Having Veolia manage our water and wastewater systems offers many benefits to the municipality – particularly having the full-time involvement of focused, skilled technical engineers who can train and upskill our existing process staff as well as improve the efficiency of treatment processes and maintenance procedures,” says Hanré Blignaut, deputy director: Engineering Planning, Overstrand Municipality.

He also cites improved energy efficiency, long-term asset preservation, value for money, and the development of small local subcontractors and creation of additional jobs as beneficial factors of an O&M contract such as this.

According to Coenie Loubser, operations manager: Overstrand, Veolia, the company is providing an operations manager and maintenance manager, complemented by support services, for the effective management of the municipality’s infrastructure. A dedicated maintenance structure will support the various aspects required to ensure the assets are maintained to improve their availability and longevity. This also gives Overstrand access to Veolia’s global wealth of technical expertise, which can be utilised for problem-solving and projects within the area.

“We are adopting a systematic approach to the development of municipal staff and appointed personnel by initiating training programmes in line with the requirements of Regulation 2834. We will also be investing in social projects and allocating 4% of the overall

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IMIESA March 2019

Municipal Insight

Key supplier: Hidro-Tech Systems Hidro-Tech Systems has been involved in the ongoing mechanical maintenance of all water and sewage pump stations, as well as water and wastewater treatment plants, for Overstrand Municipality for approximately six years, having worked through Veolia for the past three years.

contract value to exempted micro enterprises or qualifying small business enterprises, as part of our commitment to community upliftment,” says Loubser.

The phased approach adopted for skills development will take place over a three-year period and commences with assessments of the existing personnel to determine their

current skill levels. A structured NQF-level course is then identified and paired to the personnel, ensuring a focused approach to training. After completing the course, personnel can improve their classification rating as set out in Regulation 2834.

Veolia will be measured against 15 key performance indicators (KPIs) with regard to its mandate, including areas such as water and effluent quality compliance, infrastructure downtime, energy efficiency, water losses and staff training.

“Our current drinking water compliance is 99% and effluent compliance is 95%. These are included among the KPIs on the contract, and penalties have been built into the contract to encourage continuous improvement,” explains Blignaut.

Keeping up to date Although the decision to upgrade, expand and implement new technologies remains with the municipality, Blignaut points out that Veolia’s skills and expertise will ease the O&M of

Tel: +27 219491898 www.hidrotech.co.za

Municipal Insight

Key supplier: Maxal Projects Maxal Projects has been supplying, installing and maintaining chlorination systems, liquid poly systems, liquid chemical dosing systems as well as lime dosing systems to Overstrand Municipality for over 20 years.

infrastructure where new technologies have been deployed.

As part of Veolia’s drive towards standardisation, energy optimisation and reduction in chemical consumption, the company is currently conducting a number of process optimisation studies for Overstrand that might lead to potential upgrades and the implementation of new technologies to improve efficiencies and compliance. These new technologies include biological dewatering processes, AnoxKaldnesTM moving bed biofilm reactors, Hydrotech filters, as well as enhanced

coagulation and flocculation processes similar to Veolia’s MultifloTM clarification processes.

Loubser adds that, as part of a worldwide company called Veolia Environnement, Veolia Water Technologies South Africa has access to over 160 years of knowledge and experience in the management of water and wastewater services for public authorities and industrial companies. “With a solid background in water treatment technology, plant design, construction, and O&M, we can offer municipalities like Overstrand a truly holistic water solutions offering,” says Loubser.

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Chemical dosing pump skid

Chlorine Scrubber Systems

He believes that the O&M partnership offers Veolia the opportunity to showcase its skills within the Overstrand municipal environment and ultimately improve and optimise processes to ensure a beneficial relationship between contractor and client.

“Limited budget remains a challenge in most municipalities, and Overstrand is no exception.

With the implementation of this long-term O&M contract, efficiencies are to be improved, and the available funds are to be utilised optimally – to the benefit of our taxpayers,” concludes Blignaut.

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Municipal Focus | Western Cape

Tapping into the Klein Karoo When effectively managed, and its source allowed to replenish, groundwater abstraction is a viable alternative in ensuring sustained water security, with Oudtshoorn Municipality’s surrounding wellfields offering the promise of continuity of supply, when needed. By Alastair Currie

G

iven its location within the semi-deser t Klein Karoo region, Oudtshoorn is no stranger to drought conditions.

However, their extended frequency and severity are placing increasing pressure on existing dam storage capacity. Oudtshoorn Local Municipality encompasses the towns of Oudtshoorn, Dysselsdorp and De Rust.

Presently, all these towns have Level 3 water restrictions in place.

In response, the Department of Water and Sanitation (DWS) has given the go-ahead for the construction of the Blossoms water supply pipeline, which forms the main component of the Oudtshoorn Groundwater Project. This was previously earmarked as a medium- to longer-term bulk water supply augmentation inter vention, but has now been brought forward given the urgency of the situation.

The Oudtshoorn Groundwater Project entails equipping existing deep boreholes into the

Table Mountain aquifer and constructing a 22 km pipeline extending from the Blossoms wellfields to the town’s water network. Studies indicate that the supply capacity is sufficient to meet close to 50% of Oudtshoorn’s drinking water needs if dam levels at the town’s Koos Raubenheimer Dam drop accordingly. In midFebruary, capacity was sitting at around 42%.

Purely relying on the Blossoms pipeline in a ‘Day Zero’ scenario would translate to around a daily delivery of 50 ℓ per person.

The pipeline will also be linked to the existing Klein Karoo Rural Water Supply Scheme, which includes supply to Calitzdorp, falling under the nearby Kannaland Municipality. Currently, Calitzdorp does not have a secondary water source if its Nels Dam runs dry. Level 4 restrictions are currently being applied and the storage level recorded in February was at around 7.4%. This has required bulk water to be delivered to the town in various forms, including bottled water.

Blossom’s two-phased approach Split into two phases, the estimated total cost of the Blossoms pipeline project is R92 million. Neil Lyners and Associates has been appointed as the lead consulting engineer, responsible for overall design and project management of the pipeline and booster pump station, working in conjunction with Oudtshoorn’s municipal engineering team.

Approximately R50 million will be allocated for Phase I, with construction expected to commence in July 2019. An initial amount of R30 million was allocated to the DWS towards the end of 2018 by the National Disaster Management Centre. Additional funding will be sourced from the DWS, the Western Cape Provincial Government, and Oudtshoorn Municipality.

The scope of works in Phase I includes: the equipping of the boreholes (mechanical and electrical); the establishment of a pump line from these boreholes to a balancing reservoir;

Oudtshoorn’s Koos Raubenheimer Dam has a storage capacity of approximately 9 200 000 m3

IMIESA March 2019

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Municipal Focus | Western Cape

and the installation of a gravity water main from the balancing reservoir to the outskirts of the town.

During Phase II, the plan is to extend the gravity main and connect it to existing reser voirs within Oudtshoorn. This will include the installation of a booster pump station on the line.

Further afield, additional wellfields are also being investigated in the Calitzdorp area to augment the western part of the current rural supply scheme. The intention is to supplement supply when the Nels Dam drops to critical levels.

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IMIESA March 2019

With augmentation from Blossoms, the Dysselsdorp wellfields will also be sufficient to supply water to Dysselsdorp and the eastern regions of the rural scheme. A future project could also see the supply of water to the town of Dysselsdorp from the Rust-en-Vrede catchment waterfall.

For Oudtshoorn itself, the next phase in terms of longer-term storage capacity will be the building of the new De Kombuis

Dam, situated higher up in Schoemanshoek, which will supply irrigation water to the farming community in this separate catchment area. Once on-stream, De Kombuis is expected to add an additional 6 000 000 m3 to 7 000 000 m3 of storage capacity. This will free up all water associated with the Koos Raubenheimer Dam for dedicated municipal supply to the town’s residential and commercial potable water users.

Municipal Focus | Western Cape The new booster pump station

Pipe-laying outside the town of Beaufort West

Drought relief for Beaufort West

T

he Beaufort West Municipality emergency bulk water supply project was initiated to counter the severe drought conditions being experienced at the end of 2017. There was no water in the town’s Gamka Dam and existing boreholes could not supply sufficient water to meet current and future demand.

To alleviate the situation, the municipality applied for funding from the Western Cape Provincial Government, which was then sourced via the Department of Rural Development. Based on its three-year panel tender, Neil Lyners and Associates (Lyners) was appointed as the main civil engineering consultant and project manager.

The project was executed under the GCC 2015 contract at an approximate value of R23 million (incl. VAT). Due to strict expenditure deadlines to be met by end of March 2018, installations took place from January to April 2018, which was the main and most notable achievement of this project. The engineers had to ‘feed’ the contractors with final designs as they were installing pipes.

“Recent recorded historical water demand indicated that an upgrade was long overdue, since demand had already exceeded the yield capacity of Beaufort West’s existing water resources, excluding the Gamka Dam,” explains Francois van Eck, technical director, Neil Lyners and Associates. “The overall objective was to utilise the available water sources more effectively in order to ensure sustainable longer-term supply.”

The project scope included new bulk water pipelines, the mechanical and electrical equipping of five existing boreholes, and the construction of a new booster pump station at the existing reclamation plant. To ensure that the added water sources reached the community, Lyners also assisted the municipality with a leak detection programme to minimise losses in the water network.

Currently, Lyners is executing a pilot project in Beaufort West, which entails the replacement of traditional and prepaid water meters with smart prepaid meters.

This will enable the municipality to manage its potable water consumption much more effectively.

Typical mechanical and electrical borehole equipment installation

“From our George office, we’re assisting most of the local municipalities within the Garden Route and Klein Karoo regions, as well as Karoo Hoogland Municipality in the Northern Cape. Our focus is mainly on water and sewer bulk supplies, in addition to general civil, structural and electrical engineering infrastructure projects,” Van Eck concludes.

Professional team: Main civil engineering consultant and project manager: Neil Lyners and Associates Mechanical/electrical engineering subconsultants: MNE-OAK Environmental assessment practitioner: Sharples Environmental Services Main civil engineering contractor: De Jagers Civil Contractors Mechanical and electrical subcontractor: TG Electrical

Project scope: Beaufort West emergency bulk water supply • Connect five boreholes to the new booster pump station, with uPVC rising mains of 75 mm, 90 mm, 110 mm and 160 mm in diameter • New 200 mm diameter uPVC rising main from the new booster pump station to the town’s reservoir • New booster pump station with capacity of 40 ℓ/s • New mechanical and electrical installations at the boreholes and pump station • New security fences and alarm systems at the boreholes and around the pump station building • Electrical and control associated infrastructure within the MCCs for boreholes and pump station • Telemetry/Scada to tie in the boreholes and pump station with the existing bulk water supply system • 15 km of new pipeline

IMIESA March 2019

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Municipal Focus | Western Cape

Beyond durability with Flowtite GRP An approximately R1.5 billion upgrade at the City of Cape Town’s Zandvliet Wastewater Treatment Works (WWTW) in Macassar will incorporate glass-fibrereinforced pipe (GRP) on critical sections.

S

ewerage systems are among the most highly corrosive environments faced by process engineers, which means that every integrated component has to be rigorously evaluated before being specified for a new installation or upgrade. When it comes to wastewater treatment plants, two of the most commonly adopted materials for pipe connections, aside from concrete, are stainless steel and GRP. However, when it comes to large-diameter pipes, stainless steel comes at a high cost, while GRP is far more price-competitive across the board. In the case of Flowtite South Africa’s range, products have an envisaged life of 150 years or more, which makes the return on investment calculation even more attractive.

Flowtite GRP’s long-term durability has been consistently proven on projects worldwide and confirmed by materials experts at the Flowtite Centre of Excellence in Norway. These studies demonstrate that there’s no evidence of corrosion or erosion, even decades later: Flowtite remains resistant to aggressive elements like acids and gases. Plus, nothing adheres to the walls: they remain very smooth, which is a unique feature not shared by other materials.

Case studies A classic example is the Enga WWTW in Sandefjord, Norway. The plant’s marine outfall was installed in 1975. In 2008, a section of the ND 500 mm diffuser was brought ashore and its condition and mechanical properties tested. After 33 years, the internal condition was near perfect. The same was true of the external surface, despite being constantly exposed to seawater.

In South Africa, Flowtite carried out a similar exercise at the Bellville Main Sewer close to the Bellville WWTW in Cape Town, this time examining a 17-year-old section. Again, the interior had an ‘as new’ condition. Modernday developments, such as new resins and glass composites, now extend Flowtite GRP’s legendary durability even further.

Zandvliet Within the City of Cape Town, Flowtite’s GRP solutions have been part of the infrastructure landscape since 1993. For the Zandvliet project, Flowtite’s scope, valued at around R15 million, varies from 500 mm to 1 400 mm diameter GRP pipes, plus the supply of GRP fittings, flanges and manholes: essentially, a complete solution for the conveyance of wastewater within the revitalised plant. All pipes have an SN 10 000 stiffness.

These GRP products will be manufactured at Flowtite’s factory in Germiston, Gauteng, which is capable to producing up to 1 km of pipe per day (depending on the diameter, pressure and stiffness) to meet South Africa’s and Africa’s water and wastewater requirements.

“Flowtite prides itself on the ability to manufacture custom designs in any shape or form. These include our puddle coupling flanges, which go up to 600 mm in width at Zandvliet. Puddle couplings ensure a watertight seal at points where pipe sections pass through concrete walls. Another example is our GRP manhole chambers,” explains Heinrich Mostert, regional manager, Flowtite South Africa.

Flowtite SA worked with Aurecon, the project’s lead consulting engineers, to perfect the

design of the GRP elements. Main contractor Stefanutti Stocks will be responsible for their installation.

The upgrade meets future growth projections within the Khayelitsha, Delft, Blackheath and Eerste River areas. According to the City, the new plant is set for commissioning by December 2023.

“Flowtite currently has GRP products installed at all major treatment works within the City of Cape Town. The most recently completed plant is the Fisantekraal WWTW, where the entire pipe network is composed of Flowtite GRP. Alongside Zandvliet, we will also be involved in a number of future upgrades within Cape Town.

So, exciting times are ahead for Flowtite,” Mostert concludes.

IMIESA March 2019

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Municipal Focus | Western Cape

The future of sustainable sludge management The City of Cape Town plans on building three centralised biosolids beneficiation facilities in a move to establish a more sustainable sludge management chain. By Danielle Petterson

T

he use of activated sludge treatment processes for wastewater can result in large quantities of excess primary and/or waste activated sludge – the treatment and disposal of which presents a growing challenge, both in terms of treatment and disposal cost, and environmental legislation.

The answer to this challenge may lie in anaerobic digestion (AD).

Sven Sötemann, head: Development and Infrastructure Planning for the Wastewater Branch, City of Cape Town, explains that Cape Town is in a unique situation when it comes to anaerobic digestion.

The city has 25 wastewater treatment facilities, of which 15 are activated sludge wastewater treatment facilities. The majority of these 15 facilities were originally designed as extended aeration plants, without primary sedimentation and long sludge age bioreactors.

As a result, only five of the facilities originally had anaerobic digesters.

Of the five, three digester installations are ambient-temperature, unmixed digester facilities from when the treatment plants consisted of only trickling filters; two installations are heated and mixed, explains Sötemann. Currently, one heated (35°C to 38°C) and mixed digester complex and one ambient temperature and unmixed digester

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IMIESA March 2019

complex are in use, while the other three were decommissioned years ago due to concerns about their structural integrity.

The city recognised the need for a new and sustainable sludge treatment and disposal approach and, after several years of planning, Cape Town’s Wastewater Branch has received approval for the establishment of two centralised biosolids beneficiation (sludge treatment) facilities (BBFs), with the aim to establish a third facility in the future.

By establishing centralised AD facilities rather than installing digesters at each individual treatment plant, the city is able to harness economies of scale at both capital and operational levels, says Sötemann.

Managing Cape Town’s sludge The City of Cape Town currently disposes of its dewatered primary sludge at a hazardous landfill located within the city’s boundaries.

Dewatered waste activated (secondary) sludge is applied to ‘sacrificial’ farmland – agricultural land that is used to grow animal feed.

However, new national solid waste legislation seeks to divert organic material from landfill and, in future, legislation will prohibit the disposal of sewage sludge at landfills. While waste activated sludge may be deposited on land used to grow animal feedstock, Sötemann reports that available agricultural land is

Anaerobic Digestion & energy opportunities in SA The methane-rich biogas produced via AD presents an untapped renewable energy resource with several prospects for the South African wastewater industry.

Although feasibility studies confirm a high potential for biogas-to-energy uptake in the South African municipal sector, several critical steps are required before a municipality should invest in a biogas plant, including the optimisation of upstream sludge management processes and operation of anaerobic digesters.

To this end, WISA will be rolling out two mainstream training courses in 2019, focusing on: 1. Wastewater sludge management, anaerobic digestion and plant optimisation 2. Conducting energy audits at a WWTW, identifying areas and means to reduce energy consumption.

The City of Cape Town hosted two of the pilot training courses and Sötemann reports that the course was very valuable and highly relevant for South Africa’s AD needs.

Municipal Focus | Western Cape

running out, and an alternative solution for the disposal of both primary and waste activated sludge is needed.

It was, therefore, decided to provide BBFs to cater for the Cape Town’s future sludge handling, treatment and disposal needs. The facilities will incorporate imported sludge cake offloading and storage facilities, thermal hydrolysis sludge pretreatment, high-rate anaerobic digestion, digested sludge dewatering, sludge liquor treatment, and combined heat and power processes.

Funding for the first two facilities (Northern and Southern BBF installations) has been approved, with the design for the Southern BBF almost complete. The Southern BBF is anticipated to go out to construction tender early this year, while the Northern BBF project is expected to go out for professional services tender during the course of the year.

The Southern BBF, located at the Cape Flats Wastewater Treatment Works, will be constructed on a brownfield site, making use of the three existing 1 800 m3 anaerobic digesters. At an estimated project cost of approximately R650 million, this facility is expected to be completed by 2023. The greenfield Northern BBF will be completed over three phases, and is expected to reach completion two to three years after completion of the first installation, at an estimated total cost of R1.2 billion.

According to Sötemann, the wastewater branch initially explored potential synergies

with other City departments, such as Solid Waste; however, it was decided to provide dedicated sludge treatment facilities for wastewater sludge.

The City is currently not sizing the BBFs to accept waste from surrounding industries, as the capacity is needed to accommodate Cape Town’s current wastewater sludge streams. Each centralised BBF will receive dewatered sludge cake from approximately five to six surrounding ‘donor’ wastewater treatment works (WWTWs). The centralised facilities are being designed to accommodate the ultimate sludge production capacities of the surrounding WWTWs, and have been positioned to minimise travelling distance from the donor plants.

However, Sötemann says the Northern and future Eastern BBF may have spare capacity, in which case the city will explore the option of accepting additional sludge or clean organic waste from industry and adjoining municipalities for digestion.

Commoditising waste The benefit of anaerobic digestion is its simplicity, its relatively low-cost operation, and its ability to produce biogas, which allows for heat and energy production.

According to Dr Marlene van der MerweBotha, director, Water Group Holdings, electricity is one of the highest cost items on the operational budgets of energy-intensive WWTWs; however, when operated correctly, AD allows WWTWs to produce their own electricity and heat,

thereby saving on operational costs and reducing their reliance on Eskom.

Cape Town’s strategy is to implement thermal hydrolysis in order to hydrolyse the sludge upstream of the AD to improve its digestibility, and to achieve a pasteurised treated sludge product, which will allow for the digested sludge to be used beneficially for a larger number of end uses. The biogas produced from the high-rate anaerobic digesters will be used to generate steam for the thermal hydrolysis process, while the balance of the biogas will be used to fuel combined heat and power (CHP), which will produce heat and electricity for on-site use.

For the Southern BBF, the generated electricity will be able to supply approximately 70% of the host WWTW’s current electricity needs, thereby offsetting some of the costs of the facility. “We also hope to develop a small future income stream from selling the beneficiated biosolids,” says Sötemann.

Sustainable waste management “The City of Cape Town’s wastewater treatment plants are still among the best in the country when it comes to treated effluent compliance; however, the recent drought has posed some challenges and raw wastewater flows into our plants have decreased by between 30% and 35%.

Although we were expecting the nutrient load to remain the same, we have found that nitrogen and phosphorus loads have increased and, therefore, some of our plants are struggling in terms of their nitrogen removal performance. Therefore, the new designs will take into account the change in our wastewater characteristics,” says Sötemann.

“In terms of sustainability and sludge disposal, this project will be a big leap forward. Our current methods are no longer considered sustainable and this new step forward in sludge management will contribute to the municipality’s plans for making Cape Town a sustainable city.”

IMIESA March 2019

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Municipal Focus | Western Cape

Trenchless innovations for Cape Town Innovative trenchless design and methodology, coupled with the ability to adapt to changing circumstances, defined the project for the rehabilitation and upgrading of the The ribbed pipe was divided Sanddrift Bulk Sewer, which into 3 m long sections and lowered into a shored excavation won the 2018 Joop van Wamelen Award of Excellence.

Due to severe corrosion, the existing sewer had become a mushroom shape, presenting significant design challenges

To increase the incline, ribs were welded on to the pipe to suspend it at increased cumulative eccentricities

F

ollowing minor collapses between 2003 and 2006, and subsequent condition assessments, it was recommended that sections of the Sanddrift Bulk Sewer (SBS), located just upstream of Montague Gardens in Cape Town, be closely monitored and rehabilitated.

Upon further investigation, it was found that a number of sections of the over-fourdecade-old sewer were significantly degraded and in need of rehabilitation. Furthermore, the new Bridgeway Sewage Pump Station rising mains from Century City, which will discharge halfway down the existing 2 km SBS route, is expected to reach a peak discharge of 110 ℓ/s in the next 10 to 15 years, adding to the SBS’s already large catchment area, and flow. This increase in flow would exceed the future estimated peak wet weather flow capacity of the existing SBS, necessitating an upgrade downstream

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IMIESA March 2019

of this discharge point. The upstream section has enough hydraulic capacity to allow for trenchless rehabilitation.

The rehabilitation challenge The existing sewer consisted of reinforced concrete pipes with dolomitic aggregate and sacrificial lining. However, due to various sewerage rising mains of neighbouring catchments discharging at a constant flow into the upstream section of the bulk of the SBS, the sewer has been subjected to severe corrosion above the water line (only) into a non-circular/near-mushroom shape.

“Corrosion of the alkaline concrete sewer pipes occur when accumulated hydrogen sulfide gas in the effluent is released by turbulent flows or discharges to condensate

on non-submerged sewer pipe walls to form corrosive sulfuric acid. In certain sections, the sewer had corroded right through the pipe spring-line to reveal external encasement concrete,” explains Konrad Röhrs, associate engineer, Aecom.

As the consulting engineers, Aecom concluded that the section of the sewer upstream of the Bridgeway rising mains would have just enough capacity to allow for the increased future flow estimates, and determined that the installation of a close-fit inverted or pull-in cured-in-place-pipe (CIPP) rehabilitation lining in the existing SBS was the only viable trenchless solution.

However, the mushroom shape of the existing sewer presented a significant design challenge and Aecom needed to compile a 3D computer-aided finite element model (FEM), mirroring the expected mushroom-shaped cross-section profile and constraints of the expected liner within the existing sewer.

The ‘ASTM 1216: Standard Practice for Rehabilitation of Existing Pipelines and

Project team Client: City of Cape Town Consulting engineer: Aecom Contractor: CSV Construction Subcontractor: Tuboseal

Municipal Focus | Western Cape indentation/curvature around the corroded sill above the constant discharge flow level. This would be compounded by the high water table exerting external pressure on the liner. Moreover, the inner diameter of the existing sewer was expected to vary significantly along its length due to the severe and potentially varied corrosion conditions.

The solution

Conduits by the Inversion and Curing of a ResinImpregnated Tube’ design code only accommodates for circular linings with an allowance for ovality of up to 10%.

The mushroom shape of the corroded sewer was not only expected to exceed this tolerance, but also to have a negative

Using the 3D computer-aided FEM analysis, Aecom was able to explore resin and liner options, applying a realistic and calibrated set of ASTM 1216 design code parameters.

The team found that adding an additional calibrated safety factor (increasing the lining wall thickness by an additional 20%) could be applied to accommodate for the non-circular shape of the sewer.

In order to mitigate variances in diameter along the corroded sewer length, the appointed contractor, CSV Construction, supported by Tuboseal and Aecom, selected an un-reinforced felt liner with a diameter slightly above the average of the actual measured diameters of the existing corroded pipes.

Sustaining communities

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Joop van Wamelen Award Every year, the Southern African Society for Trenchless Technology (SASTT) awards the Joop van Wamelen Award of Excellence to a leading project team in recognition of exceptional contributions to the active promotion and implementation of trenchless technology in Southern Africa.

The un-reinforced liner was able to allow a 5% to 10% stretch to ensure a close fit of the liner around the circumference of the existing pipe.

Where the existing pipe was smaller than the liner circumference, longitudinal creases perpendicular to the pipe circumference could potentially form; however, it was expected that well-cured, resin-filled creases would cure into structural webs – ultimately adding to the structural stiffness of the cured liner.

RĂśhrs further explains that this was preferable to a non-close-fit lining, which could result in an uneven invert of the pipe due to sections of the liner potentially becoming buoyant from ingress groundwater pressure, which would in turn negatively affect the

Municipal Focus | Western Cape

By omitting running costs of a temporary over-pumping system, the team secured significant cost savings

The CIPP installations had to be conducted on busy public roads The main over-pumping system

hydraulic capacity of the rehabilitated pipe.

A pre-liner was also installed in advance of the actual CIPP lining, in order to protect the lining material when installed under hydrostatic pressure (pre-cure).

Tuboseal installed the liner in seven portions – from both up- and downstream positions – with the longest portion being over 100 m. The end result was a set of seven cost-effective, well-cured and rehabilitated close-fit lined sewer sections with a total length of over 700 m, achieved well within the programme schedule of the overall contract.

The installation team faced various difficult technical challenges, including having to conduct the installation under and from within the underground parking garage of

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IMIESA March 2019

the Sable Square Shopping Centre. Through excellent coordination and communication, the installation was safely conducted, with minimal impact and disruption to the public.

“Although we mitigated a lot of risk by the additional design measures and simulations, this remained a non-standard installation and a lot of risk still applied. We insisted that Tuboseal have a very thorough quality assurance plan to provide security and monitor conditions on-site. We must commend Tuboseal on the fact that they presented us with a set of very thorough quality control documents and records – making post-installation inspections much easier and informed – so that no sections with any potential fault conditions were left unresolved or approved,” says Röhrs.

Adapted slip-lining method The section of the SBS that required

upgrading could not follow the exact same route as the existing and still-active SBS. The upgraded ND 750 mm line provided to the SBS followed a new route; however, this resulted in the potential isolation of a small subcatchment of the existing SBS. This was overcome by ensuring the new sewer retained the same vertical alignment in this position as the existing sewer, to continue receiving a reduced flow of 30 ℓ/s – reduced from 120 ℓ/s. However, the reduced flow in the old large-diameter pipe brought a concern of sedimentation, says Röhrs.

In order to ensure that the reduced flow would maintain scour velocity along this section of the bulk sewer, an adaptation to the normal slip-line method was proposed. This involved using a slipline of a smaller ND 200 mm HDPE at an increased slope, by suspending it in 25 mm thick perpendicular HDPE extrusionwelded ND 450 mm chamfered flanges/ribs, spaced at 1.5 m intervals. The ribs work to suspend the pipe at increased cumulative

The existing bulk sewer was upgraded to ND 750 mm

eccentricities, resulting in the required increased incline.

Due to the limited workspace in the road reserve, the pipe was divided into 3 m long sections, to be lowered into a shored excavation, and joined by external electrofusion-welded couplings. This jointing method would ensure unobtrusive flow, unlike butt-welded beads, which could infringe on the flow of the effluent or strain any suspended solid materials, explains Röhrs.

Innovative flow diversion As part of the tender design, the contractor was required to accommodate the diversion of the bulk effluent flow resulting from the Brooklyn Chest Sewage Pump Station, where the SBS commences, through a 700 m long ND 450 mm continuously welded HDPE pipe.

Röhrs explains that although the safe and effective system of silent pack pumps was provided for as per the tender design, the project team identified the opportunity for coupling the proposed 700 m ND 450 mm HDPE bypass rising main to the existing Brooklyn Chest pump station instead.

Following investigation and testing, the two

rising main systems were joined effectively. By omitting running costs of the temporary overpumping system, the team was able to secure significant cost savings for the City of Cape Town.

Furthermore, the local reticulation systems were intercepted and accumulated at a central point, halfway along the rehabilitation section, before being tied in to the main ND 450 mm HDPE bypass rising main.

By combining localised bypass/over-pump systems and tying this into the main rising main, additional costs savings were realised.

These cost savings also allowed the project team to relocate the existing dilapidated and severely corroded rising main discharge

chamber, previously positioned in a residential children’s play area, into the nearby public road reserve in a new, corrosion-protected, reinforcedconcrete chamber.

Mark Brodovcky, Project Engineer for the City of Cape Town, commended the team on this innovative method, which was only conceptualised after the tender had been awarded and resulted in savings of several million for the city.

Röhrs believes the overall design was well workshopped and executed by the project team, ultimately extending the life and functionality of the local sewer system. “A year later, we are very happy to see that the design and concept have been successful and the system is running as expected.”

83RD IMESA CONFERENCE

02-04 October 2019 DURBAN INTERNATIONAL CONVENTION CENTRE

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WORLD WATER DAY

World Water Day 2019 Leaving no one behind

700 million people worldwide could be displaced by intense water scarcity by 2030

WHY ARE PEOPLE BEING LEFT BEHIND WITHOUT SAFE WATER?

80% 80% of countries have insufficient finances to meet national water, sanitation and hygiene targets

1. Sex and gender 2. Race, ethnicity, religion, birth, caste, language, and nationality 3. Disability, age and health status 4. Property, tenure, residence, economic and social status

2.1 billion 2.1 billion people live without safe water at home

Women and girls are responsible for water collection in 8 out of 10 households with water off-premises

Nearly two-thirds of the world’s population experience severe water scarcity during at least one month a year

884 million 884 million people lack basic water services

Globally, 80% of the people who have to use unsafe and unprotected water sources live in rural areas

159 million Around 159 million people collect their drinking water from surface water, such as ponds and streams

IMIESA March 2019

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83RD IMESA CONFERENCE

02-04 October 2019 DURBAN INTERNATIONAL CONVENTION CENTRE

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Water & Wastewater

Rethinking filtration Tracing its roots back to 1964, Mecana has cemented its position as a pioneer in the field of wastewater treatment. It’s no wonder that local solutions provider Logical Water has added the brand’s patented pile cloth filtration products to its offering.

W

ith over well 2 000 cloth media filters operating in more than 1 100 different treatment plants worldwide, Jason Gifford, director at Logical Water, believes that Mecana’s OptiFiber® pile cloth filtration products can meet the challenges of the South African industrial, mining and municipal wastewater sector.

A structure for solids separation What sets the patented process apart is the structure of the pile fabric used. “During filtration, the individual pile fibres, which are not unlike animal furs, lie flat to form a dense and effective barrier to suspended solids,” explains Gifford.

“Each filter fibre acts like a single, long, thin grain of sand; when wet, they sit on top of each other, forming a barrier to particles attempting to pass through, just like a deep bed of sand,” he continues.

This key feature allows for higher separation efficiencies, greater hydraulic throughput and extreme tolerance to shock loadings. It also allows for minimal backwash effluent volumes.

During the cleaning process, the fibres lift briefly within the suction beam, enabling the retained solids to be removed easily. The filters are always fully submerged and always online, even during backwash cycles.

Benefits of Mecana’s OptiFiber pile cloth media filtration • High separation efficiency • No pumping necessary • Low maintenance • No chemical cleaning agents required • Low operational costs • Simple installation

Stricter norms and guidelines Originally developed 35 years ago, as clarifiers after rotational biological contactors (RBCs), Mecana’s pile cloth media filters are commonplace in the international wastewater treatment market.

“Around the world, governments and institutions have turned their attention to the quality of municipal and industrial wastewater, with a particular focus on two essential objectives – i.e. the protection of public health and the protection of the aquatic ecosystem.

“As a result, we’ve seen stricter norms and guidelines emerging, especially relating to suspended solids, phosphates, micropollutants and micro-plastics. At the same time, energy prices are increasing and CO2 emissions targets are getting lower, highlighting that the time for energy-efficient solutions that are technically

effective is now and this is where pile cloth filtration media really help.”

Cutting emissions and micropollutants When used in conjunction with powderedactivated carbon (PAC) to adsorb dissolved micropollutants, which is both efficient and cost-effective. The pile cloth media filter then removes the PAC from the process flow, producing a high-quality final effluent with very low levels of suspended solids.

“Independent studies have shown that pile cloth media filters are a very practical and highly efficient technology for removing PAC particles and the micropollutants along with them,” Gifford notes.

Mecana’s OptiFiber pile cloth filtration products are extremely energy efficient because they have very low process headloss, meaning that they fit into most existing hydraulic profiles, eliminating the need for relift pumping stations and the associated power usage.

“Energy is only required during the short backwash cycles – the rest of the filtering typically being gravity flow,” he adds.

A filter for every application Turning to application, Gifford points out that Mecana’s pile cloth media filters can be used in almost all cases where there is a need to reduce suspended solids.

The filters can also be configured differently, depending on the application. The range includes two configurations for lower and higher volumes; the Drum Filter, for lower flow rates and the Disk Filter configuration, typically used in flows greater than 100m3/h. Due to their solids removal efficiency, these filters are assisting WWTWs to replace traditional chemical disinfection systems with UV systems, by reducing suspended solids to better than 5mg/ℓ ensuring safer operating conditions at the works and for the environment.

www.logicalwater.co.za

IMIESA March 2019

25

Water & Wastewater

Improving safety through odour control As part of the growing concern for operator safety at waste water treatment plants, Buffalo City recently requested the installation of an odour control system as part of their R187 million expansion project at Reeston Waste Water Treatment Works.

By Annejan Visser*

W

orking on the Reeston Wastewater Treatment Works (WWTW) upgrade, QFS was responsible for the fast deliver y and implementation of an I-BOx® 7010 odour control unit. The odour control was installed for the inlet works

I-Box odour control units advantages QFS offers I-BOx odour control units that can drastically help alleviate safety concerns with the following advantages: - fast implementation time - plug and play - compact and easy to deploy - simplified design - 99% effective H2S removal

section of the plant, as these areas are highly prone to hydrogen sulfide (H2S) generation due to the turbulence created through degritters, screens and various other equipment. The turbulent water allows the gases contained within the water to be released as the water follows its course though the inlet works.

The H2S released in these works can be a severe safety concern for the roughly 80 personnel operating at the Reeston WWTW, with high concentrations leading to severe safety risks of operators, as per Table 1.

The importance of odour control Table 1 categorically highlights the importance of odour control and its effect on plant safety for operators. Typically, H2S concentrations measured at inlet works are around

300 ppm, which can cause severe discomfort and necessitate additional medical care and treatment for personnel affected.

This could lead to minimised personnel on-site, which would mean fewer operators to maintain and operate equipment. This which can ultimately lead to strain on the plant and therefore strain on metropolitans and communities, as sewage cannot be treated effectively.

By implementing odour control measures such as the I-BOx, these safety concerns can be effectively mitigated, ultimately improving worker safety and the functioning of wastewater treatment plants. *Annejan Visser is a process engineer at QFS.

Table 1 Toxicity and effects of H2S at various concentrations

H2S concentration Toxicity Effect 0.1 – 3 ppm Odour threshold 3 – 10 ppm Offensive odour Rotten egg smell 10 – 50 ppm Headache, nausea, throat and eye irritation 50 - 100 ppm Eye injury Leads to serious eye injury 100 – 300 ppm Conjunctivitis, respiratory tract irritation, olfactory paralysis Coughing, eye irritation, loss of smell after two to five minutes 300 – 500 ppm Pulmonary edema Imminent life threat 500 – 1 000 ppm Strong nervous system stimulation apnea Loss of consciousness, death possible in 30 to 60 minutes 1 000 – 2 000 ppm Death Rapid unconsciousness (Source: ‘Odor prevention and control in process plants’, Chemical Engineering, Feb 2002, pp. 50 – 55)

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IMIESA March 2019

Water & Wastewater

Innovative aeration control

Balancing the biological stage of a wastewater treatment plant can be a tough act without the right tools. However, with innovative aeration control, industrial and municipal wastewater plants can ensure their operations are controlled and economical.

V

acomass®, by the Binder Group, provides wastewater professionals with precise and efficient aeration control in the biological treatment process. Supplied locally by Logical Water, the Vacomass® system features components that are matched to each other for precise measurement, control and distribution of air in wastewater treatment plants. The Vacomass® system comprises the jet control valve, various diaphram valves (for smaller pipes) and the flexcontrol interface.

“Aeration is the single biggest cost of treating wastewater. Wastewater works install highly efficient blowers and diffusion systems and then negate the efficiency gains by installing control valves that were never designed for controlling air,” explains Jason Gifford, director at Logical Water.

Biology under control Aeration air has to overcome static and dynamic back pressures on the

way to the treatment tank. These factors change over time and are hard to control, so even very small changes will have a significant influence on the air distribution and dissolved oxygen (DO).

This is exactly where the Vacomass® offering is extremely effective, Gifford points out.

“The Vacomass® flexcontrol system continuously monitors the predetermined process parameters and can immediately detect the smallest deviation from the setpoint.

This precision control coupled with the Vacomass® jet valve not only ensures pressure losses across 95% of the stroke of less than 2 mbar, but also provides the process controller with a system that they can confidently operate, and which allows them to consistently maintain the levels of DO at the desired setpoint within 0.2 mg/ℓ,” he adds.

The level of control afforded to the plant operator or process controller is typically only possible when a group of specialists work together on the plant to make adjustments. This means that once the adjustments have been made no further fine-tuning can be done by the plant operator over a period of weeks or even months as these specialists are required to be present to make these changes. This approach is simply not practical for a WWTW.

What sets Vacomass® apart is that it ensures that air is supplied according to actual oxygen demand in the various basins and aeration zones of the plant. This intuitiveness ensures that plant operations are not only well controlled but that energy consumption is also significantly reduced. The Vacomass® system works within the existing plant infrastructure and does not replace the Scada, PLCs, blower MCP, or any other major components. It simply sits within the control system and acts as a slave module utilising signal inputs that are typically already in place, this makes retrofits simple and economical.

Modular The modular design of the Vacomass® measurement and control system operates on the building block principle and, depending on plant size, control concept and specific requirements, the system components of the Vacomass® product family can be supplied individually or in combination with each other.

The Vacomass® product family features 16 modules, each with their own function, which can seem overwhelming; however, with support from Logical Water and Binder, wastewater plants can select the most effective solution for their operations.

“Each plant has its own requirements, which is why we sit down with our customers and develop control strategies that look at key factors including the number of aeration tanks, their geometry, their scope of supply and whether or not there is a need for integration of existing equipment, to select a Vacomass® product that will work for them,” Gifford notes.

“Our work with the Vacomass® system in South Africa has shown that the payback on investment ranges from 12 to 36 months, which is reassuring for operators in a developing country. So not only is the system cost-effective, it is also easy to operate and offers the security that comes with full local support.”

Intuitive operation Preventing the under or over supply of oxygen in the biological process is essential for an efficient operation. Too much or too little oxygen can lead to problems that include exceeding the legal limits of the effluent quality of the plant, uneconomical operations and process disadvantages.

www.logicalwater.co.za

IMIESA March 2019

27

Meters, pipes, pumps & valves

Smart versus mechanical Water resource management and infrastructure require sustained funding, which itself requires precise monitoring and accurate billing. Marcus Thulsidas, business development director at Utility Systems, talks to Alastair Currie about how developments in smart metering are adding value and ensuring financial sustainability for municipalities.

A

dvanced metering infrastructure (AMI) is a massive growth area globally as the world becomes more urbanised and city planners fast-track intelligent IT infrastructure for today and tomorrow’s smart cities.

Within this context, there are solutions that are designed to meet the needs and budget constraints of both the developed and developing markets. These systems are scalable and can be expanded in line with growing infrastructure requirements. Within

the water sector, the main focus areas for metering are consumption monitoring, supply regulation, and timeous revenue collection for services rendered.

“Our AMI systems provide water utilities and municipalities with more control of the end point,” says Thulsidas. “This especially applies to the payment, or nonpayment, of services, as well as the measured allocation of free services, a case in point being those delivered to indigent households.

“Across the board, where Utility Systems’ utiliMeter uses next-generation severe drought and water advanced metering infrastructure shortages conditions are technology experience, utilities and municipalities must have the ability to regulate supply.

That requires remote control

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IMIESA March 2019

with smart meters. Passive systems are inefficient and a thing of the past,” he continues. “In a number of cases where we have our older (electromechanical) flow limiter devices in place, we’re helping metros and municipalities to transition to smart metering.”

“EThekwini is a good example: we started installing electromechanical meters back in 2003. Some 150 000 are still in use, mostly

Meters, pipes, pumps & valves

for resource management. In parallel, the city has been moving to AMI technologies. In the past, we also worked with the city on a school project. Our devices automatically switched off the water at the end of the school day and then automatically reactivated supply in the morning. That made a significant difference in water savings by countering overnight losses due to leaking infrastructure. There were savings of approximately 40%, school-toschool, just by using our technology.”

Utility Systems’ utiliMeter is a prime example of an AMI device that offers bi-directional communication in near real-time via the cloud or over a local private network (APN).

Cape Town Within the City of Cape Town, Utility Systems has around 250 000 water management devices installed, which form a key part of the metro’s water management strategy. Utility Systems is now upgrading the network with the roll-out of some 500 support terminals communicating with Utility Systems’ latest

mobile apps, namely the utiliPro field service app and the utiliRead mobile data collector app.

A key benefit of utiliRead is convenience: it facilitates walk- or driveby meter reading and data capture, and marks out metering routes. It will also flag any faults, as well as generate predictive maintenance reports based on system health diagnostics. In turn, utiliPro

enables technicians to manage and configure AMI devices in-field.

“In addition to consumption management, our system is also assisting the city in the identification and separation of its technical and non-technical water losses,” Thulsidas explains.

The city is currently using the technology for specific projects. These include indigent management to its installed user base. This ensures that the city can accurately monitor free basic water delivery in terms of municipal by-laws, which is currently around 350 ℓ daily. Another is the measurement and control of water to all city households as part of Cape Town’s drought intervention strategy. The current daily limit is 40 kℓ. Where consumers abuse the restrictions, the system can switch off high-volume users under exceptional water restriction conditions.

“Smart integration is the future, which will increasingly shift to prepayment technologies in line with global best practices,” Thulsidas concludes.

Meters, pipes, pumps & valves

APE Pumps adds submersible series A leader in fluid control solutions for the past 67 years, APE Pumps is extending its market penetration into new sectors.

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PE Pumps has expanded its local line-up with the introduction of a series of submersible pumps targeting key sectors, which include the water and wastewater markets, mine and dam dewatering, and irrigation. Depending on the application, capacities range up to 50 000 m3/h and pumps are available with either dry or wet motors.

Manufactured in India by APE Pumps’ group holding company, WPIL Limited, these products have a long history of successful

M, G & WQDWS series dewatering pumps

utilisation on key installations worldwide and come to market in either horizontal or ver tical configurations.

Three key submersible categories are being launched, namely: - the M, G and WQDWS dewatering pump series, providing flow rates up to 1 000 m3/h and heads up to 100 m - the MS sewage pump series, providing flow rates up to 6 000 m3/h and heads up to 70 m - high-capacity models providing flow volumes up to 50 000 m3/h at heads up to 25 m.

“A key benefit of submersible pumps is their smaller footprint, which enables engineers to develop more efficient installations.

Examples in the municipal

Submersible high-capacity models provides flow volumes up to 50 000 m3/h

MS series sewage pump

field include sewage pump stations, where our pump designs achieve optimal flows and heads,” comments John Montgomery, general manager, APE Pumps.

WPIL group companies have extensive experience in assisting clients with the design and equipping of raw water systems, booster pumps, drainage and sewage stations, plus piped water schemes. A classic example is the revamping of the infrastructure for the Blantyre Water Board in Malawi, which was completed as a joint venture between WPIL and APE Pumps.

APE Pumps is currently ranked as a 7 ME contractor in terms of the Construction Industry Development Board grading system.

Working within the group, capabilities extend from concept to commissioning. This includes hydraulic system analysis and pump selection; mechanical piping and equipment layout; instrumentation; and electrical, civil and structural engineering.

“Adding submersibles to our existing offering is an exciting development, which opens up a new world of opportunities,” Montgomery concludes.

Pump application range - Mining: dewatering systems for process and seepage water, and for lowering water level - Dewatering of dams and floodprone areas - Pumping activated sludge and raw, untreated, highly turbid water - Lift irrigation: pumping from lowlevel water sumps - Pumping waste, storm-, service and cooling water Technical specifications - Capacities up to 50 000 m3/h - Heads up to 20 m - Compact unit in monoblock design - Wide range of duties - Available with wet and dry motor options

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IMIESA March 2019

Meters, pipes, pumps & valves

SupremeServ brings solid aftermarket services KSB Pumps and Valves has announced plans to intensify its aftermarket ser vices, adding value to customer operations far beyond the supply and maintenance of its own products.

K

SB intends to expand its ser vices and engineering exper tise to include the maintenance of entire systems, reverse engineering of rotating equipment and systems optimisation. This includes the maintenance of third-party peripheral equipment in order to ensure optimal per formance of clients’ systems.

“Our aftermarket engineering teams can also remanufacture or reverse engineer equipment that is no longer available but necessar y to meet clients’ requirements,” says Grant Glennistor, division manager: SupremeSer v, KSB Pumps and Valves.

SupremeServ Globally, all aftermarket ser vices fall under the new KSB SupremeSer v

Grant Glennistor, division manager: SupremeServ, KSB Pumps and Valves

banner, which encompasses existing and new maintenance, logistics and engineering infrastructure. SupremeSer v is focused entirely on elevating customer assistance to new heights within the pump industr y, and builds on a strong histor y of more than 60 years in the South African industr y.

“SupremeSer v is a safety net that ensures KSB’s extensive South African, as well as global, infrastructure and expertise is available to support customers’ fluid transfer projects, including equipment and related infrastructure, to ensure its longterm success,” says Glennistor.

“It includes a faster supply chain with a move towards fully automated logistics functions for faster spare parts turnarounds, upgraded high-tech ser vice

centres at all KSB branches, specialised repair ser vices on all makes of pumps and related equipment, specialised welding, as well as installations, commissioning, per formance testing on site, decommissioning and other advanced field ser vice and engineering ser vices.”

With specialists in all areas, KSB SupremeSer v ser vices are available for a wide range of clients, whether for basic or large-scale, complex ser vices for power generation plants, petrochemical, bulk water supply, industrial and agricultural projects.

KSB SupremeSer v centres are situated at all local branches with spares and standard parts available within 24 hours to ser vice all 22 000 variants of its own pumps.

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Meters, pipes, pumps & valves

The water crisis in the Western and Eastern Cape regions is a stark reminder that South Africa is a water-scarce country.

Businesses and individuals have responded to pleas from local government to reduce consumption, but damaged pipes still result in major losses.

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his places an increasing strain on dam levels, which come under pressure during extended drought conditions, like those experienced in Cape Town and Port Elizabeth over the past two years. As at mid-February 2019, the overall storage capacity for Cape Town’s large dams was sitting at around 67%, and 49% for Nelson Mandela Bay.

Regular pipeline inspections are critical According to a 2018 GreenCape market intelligence report, water demand in South Africa is expected to exceed supply by 17% in 2030, with demand expected to grow from 15 billion m3 in 2016 to 18 billion m3 over this period.

“In order to address water scarcity and provide reliable water to all people, businesses and industries in South Africa, it is estimated that – over the next 10 years – an investment of around R70.4 billion is required each year in water infrastructure. This includes refurbishing and upgrading existing infrastructure, as well as new infrastructure to support population and economic growth,” the report states.

Claude Marais, general manager of Averda Sight Lines, a pipeline assessment and maintenance

specialist, suggests that, if we want to avoid running out of water, we need to take better care of our infrastructure.

“We cannot increase the amount of rainfall we get, but what we can control is how much water is lost due to leaks or breakages,” he says.

“While it would be naive to believe we can reduce this to zero, our experience shows that we can significantly cut water leaks through a programme of planned assessment and maintenance.”

As Marais points out, water utilities, municipalities and users alike can benefit by using inspection data to plan and budget for scheduled repairs and upgrades. In addition to saving water, these efforts can reduce overall maintenance expenditure by up to 70%.

Meters, pipes, pumps & valves

With or without annulus LEFT When renovating with annulus, the pipe cross section decreases. In part, the reduced transport capacity is compensated due to the absolutely smooth inner surfaces of the AgruLine pipes RIGHT When relining without an annular space, a folded and, therefore, reduced PE pipe string, the so-called Agru SureFit liner, will be pulled into the old pipe

E When it comes to the rehabilitation of steel or concrete pipes, water tanks or concrete basins, polyethylene (PE) plastic products play an essential role.

Pipes and entire tunnels with cross sections of more than 1 m in diameter are thermoplastically lined with AgruSafe concrete protection liners

ngineering plastics are among the preferred solutions for many renovation projects, thanks to factors like high chemical resistance and competitive installation costs. Either way, it’s important to distinguish whether the restoration can take place with or without annulus.

When refurbishing without annulus, the advantage is that the old inner diameter remains almost unchanged, so the media flow and transport capacity are maintained.

Here, Agru Kunststofftechnik’s Agru SureFit liner is a well-proven solution.

Folded when inserted, this liner is pulled through the existing pipe. Once in place, both ends are sealed and the pipe is pressurised

with water vapour. Heat and pressure activate the memory effect, so the Agru SureFit liner regains its original round shape and nestles like a second skin inside the old pipe.

Then for large pipe cross sections, Agru Kunststofftechnik has developed the AgruSafe concrete protection liner. The end result is a permanently sealed composite pipe, which is resistant to corrosion, abrasion and chemical media.

Annular gap When renovating with annulus, the pipe cross section is reduced because the new PE pipe must have a smaller diameter. This results in an unavoidable annular gap; however, reduced transport capacity is compensated for to a certain extent due to the smooth surface of the new PE pipe.

The rehabilitation takes place with coiled AgruLine pipes in standard lengths of 100 m and an outside diameter (OD) of up to 90Â mm.

For larger diameters, individual AgruLine pipes can be welded step by step in the excavation and pushed into the old pipe. AgruLine PE pipes range from OD 20 mm to OD 3 500 mm to meet most applications.

IMIESA March 2019

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Doing more with less The Southern African Plastic Pipe Manufacturers Association (SAPPMA) highlights the financial and environmental benefits of using thermoplastic pipes as a cost-effective way to extend budgets without compromising on quality and durability.

S

APPMA and its international counterpar ts have been researching and documenting the environmental impact of plastic pipes, comparing this data with pipes manufactured from other materials.

Results have unequivocally proved that pipe systems made from thermoplastics have much lower manufacturing and transportation costs, better long-term maintenance, and higher recyclability.

“The dramatic increase in the size of the world’s population and the

Plastic pipes are being manufactured in much larger diameters and higher pressure ranges than ever before

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IMIESA March 2019

Jan Venter, CEO, SAPPMA

corresponding strain this places on infrastructure has placed the focus on assessing the net impact products have on the environment,” explains Jan Venter, CEO, SAPPMA. “From an environmental and economic point of view, engineers are recognising that investing in plastic pipes makes sense.”

Meters, pipes, pumps & valves

through pipelines. Here again, plastic pipes have proved to save costs, owing to the fact that their walls offer very limited resistance to flow (low friction) and, even more importantly, remain virtually unchanged throughout their design life. All of this helps to keep pumping costs to a minimum and saves money on maintenance in the long run.

Studies have unequivocally proved that pipe systems made from thermoplastics have much lower manufacturing and transportation costs, better longterm maintenance, and greater recyclability

Lower transportation costs: Because plastic weighs much less than steel or concrete, it costs considerably less to transport plastic pipes.

Plastic pipe is recycled on a relatively large scale because of the high value of polymer used in the manufacturing process.”

Benefits of plastic pipe High recyclability and recovery: Plastic pipe is recycled on a relatively large scale because of the high value of polymer used in the manufacturing process. Although ductile iron and steel pipes can also be recycled, the energy cost to do so makes the process considerably more expensive than with plastics. Basic calculations show that the power consumption to recycle plastic pipe is approximately R0.09/kg compared to between R0.23 and R0.45 for steel – bearing in mind that many steel pipelines are internally lined with material that first needs to be stripped.

“Plastic pipe is not wasted and, therefore, does not contribute to environmental pollution. Every last gram of recycled pipe can be reused, although strict quality requirements set by SAPPMA allow most of it to only be used in non-critical applications,” Venter explains.

Low manufacturing energy requirements: In order to quantify and correctly assess the amount of energy used to manufacture a material or product, an embodied energy analysis is performed.

This involves assessing the overall amount of energy needed to extract the raw material, and manufacture and maintain the product.

The basic factors that influence the embodied energy of a piping system include the pipe size, type of material used, durability and design life of the system, and the amount of energy required to pump the fluid.

Test results showed that even though the material energy of ductile iron is a lot less than that of plastics in terms of mass (MJ/kg), the opposite is true when the wall thickness and mass per metre are taken into consideration (MJ/m). Similarly, the amount of carbon dioxide emitted by the production of plastic pipe is far below that of ductile iron.

Lower pumping costs: Energy shortages and high electricity costs are increasingly influencing societies around the world.

Approximately 60% of the world’s electricity is consumed by electric motors, 20% of which is for pumping. Therefore, it has become vital to consider the amount of electricity needed to pump fluids

IMIESA March 2019

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Bigger application thanks to new sizes: Plastic pipes are being manufactured in much larger diameters and higher pressure ranges than ever before. This is an exciting development that is opening up new markets and possibilities that were traditionally occupied by steel pipe.

“Globally, the plastic pipe industry is in a strong position and continues to grow its market share and influence. In South Africa, there is definitely more potential for growth through creating awareness and understanding of the various materials and combination of offerings that can be used,” Venter continues.

“At the same time, we need to create a stronger pull-through effect by increasing market acceptance. That will drive the demand by end-users, engineers and specifiers who recognise the significant energy savings and environmental benefits afforded to them by specifying thermoplastic pipes. From our side, SAPPMA will continue to ensure that clients are not disappointed by inferior products,” he concludes.

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Virtual Reality

Design review using VR Developments in the use of vir tual reality (VR) technology enable designers to develop intricate simulation models, alongside the remote assessment of existing systems, like process plants, to troubleshoot operational bottlenecks.

By Luchelle Damons*

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ypical engineering applications often see design work being done by hand and with appropriate software, usually in two dimensions (2D). Although designs are reviewed prior to the commencement of construction, design shortcomings can be overlooked, as reviews of 2D designs often lack the complete perspective that three dimensions (3D) offer.

An effective means of per forming comprehensive design reviews throughout

the project life cycle is required, in order for the design to be analysed from a holistic perspective. This would allow potential design challenges and possibilities for improvement to be identified and implemented in a time- and cost-effective manner.

The design, review and analysis of design alternatives form an integral part of any infrastructure delivery project. VR offers an innovative and effective way to perform the above-mentioned functions so as to ensure

that the best possible infrastructure solution is ultimately implemented.

2D designs can be imported into VR software.

Once in VR, the user is able to explore and interact with their design in 3D, in real time.

VR incorporates tracking of natural head and hand interactions to simulate the feeling of immersion and navigation of the virtual space, as the user wears a head-mounted device and uses handheld controls.

Walking through the design VR visualisation enables the various stakeholders involved in the infrastructure delivery project to explore, interrogate and interact with the design. These designs could include structures, P&ID (piping and instrumentation diagram) processes, plants, networks or systems. During the early project stages, the user is able to virtually ‘walk’ through the design and experience it as though construction has been completed.

If a model is visually interrogated from a virtual perspective in 3D prior to the

FIGURE 1 User analysing an engineering design using VR

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IMIESA March 2019

Virtual Reality

FIGURE 2 Realistic virtual renderings produced during the design phase of a project

commencement of construction, the design can be optimised. Since the virtual model is a 1:1 representation of the design, stakeholders will be able to gain a realistic perspective.

They could then ascertain whether there are any components that are inaccessible, identify any obstructions, note any physical design errors (such as clashing pipes), pinpoint areas where working spaces need to be revisited, model and explore design alternatives, and identify where aesthetics are unappealing, among others.

VR advantages If an error is identified as a result of design analysis through VR (as opposed to identifying the error during construction), the following will be avoided: • time spent by the engineer verifying the error and formulating a design solution • rework required, with associated abortive cost for the client, funder, contractor and engineer • delays in construction programme.

Furthermore, using VR before construction commences, to demonstrate what the design will ultimately look like, ensures that all stakeholders holistically understand the project and can accurately anticipate the end result.

The benefit of using VR as a tool to analyse an engineering design can be derived throughout the project life cycle – not just during the design phases. In addition to being an effective visualisation tool, the virtual model can store information pertaining to the respective assets within the design. This information is known as building information modelling (BIM). For

example, such information for a pump within a wastewater treatment works (WWTW) could include the pump’s model, duty, efficiency, and service/maintenance information – any data the designer deems relevant.

Therefore, while the user is undergoing a VR immersion to visualise the design in 3D, they are also able to access this additional realm of information – the BIM data – without breaking immersion. This allows the designer to gain a more complete understanding of the project, as they can experience the physical components and access relevant data simultaneously, while they navigate the virtual space.

Furthermore, programmes such as Scada (supervisory control and data acquisition), can be incorporated into the virtual model to allow for the review and analysis of a new or existing plant to take place effectively. The Scada hardware and software gathers data on the actual performance of the various components within an operational development, which can then be accessed as BIM data in VR. Being able to receive updates on the actual performance of the development remotely, while simultaneously visualising every component of that development in 3D, through VR, enables effective system management and maintenance while the development is operational. To continue the example of the pump within the WWTW: the Scada information

recorded could include the actual flows, velocities, pump efficiency, and more. If the data reveals that the pump is not operating as it should, the engineer will be able to identify the possible causes through interrogation of a 3D virtual model (and the embedded BIM data), as well as Scada information (relating to the actual operational data of the component).

To illustrate: a sudden drop in pressure could be indicative of a burst pipe in a network, or a reduction in output volume could be the result of an upstream blockage – all of which can be determined remotely by the engineer using VR. By performing design reviews and troubleshooting operational problems using VR, time and money are saved during the design phases, while the development is operational, and right to the end of the component’s operational life. While VR does not attempt to replace physical site visits, stakeholders can visit the site virtually without incurring the potential travel costs to and from site. In the same way, if a problem requires specialist input, the specialist can virtually visit the site repetitively to perform analysis, irrespective of geographical boundaries.

By incorporating VR into a project workflow, the engineer can design more efficient and well-thought-out developments, with reduced design, construction and operational costs. Work will be executed as though all stakeholders had foresight into how their designs will be translated into reality – with VR, that foresight is possible.

Through visualising and experiencing the VR model – from project initiation to the end of the operational life – engineers can better understand engineering problems.

Ultimately, through the analysis of designs with VR, engineers become equipped to provide robust, holistic and innovative infrastructure solutions. *Luchelle Damons is an urban infrastructure civil engineer at iX engineers.

FIGURE 3 Complex engineering and operational data embedded within the virtual model as BIM

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Waste Management

Poor waste planning and health While district and local municipalities are legally required to develop and implement Integrated Waste Management Plans (IWMPs) that reflect national environmental priorities, widespread non-compliance is exposing communities to an increased risk of disease.

A

combination of budgetary constraints and skills gaps, plus inadequate oversight fr om government, has left many municipalities without a working waste management plan.

“Where these are in place, insufficient commitment to implementation is often observed,” says Andrew Caddick, senior environmental scientist at SRK Consulting.

“The Depar tment of Environmental Af fairs’ National Waste Management Strategy must inform strategic priorities at provincial government level, and these priorities must cascade down to district and local municipalities’ IWMPs, but it seems that this requirement is not well enforced,” Caddick explains.

In the absence of professional waste management planning and implementation, landfills are poorly managed, dumping is often uncontrolled and waste-related infrastructure lacks proper maintenance, among other issues.

As well as visual and air-quality considerations, the fundamental risk of inappropriate waste management is the onset of health issues in communities.

“Rural areas are often characterised by poor waste management practices.

People in these areas often rely on

surface and groundwater for domestic purposes, putting these communities at risk of exposure to waterborne diseases and contamination of water sources,” Caddick continues.

Situation analysis, execution IWMPs aim to reduce the amount of waste generated, guide the reuse of waste, and promote recycling. The legislated process required to develop an IWMP involves a situation analysis, setting goals and targets, selecting the best approaches to reach these targets, compiling the plan, and aligning and integrating the IWMP with the municipal Integrated Development Plan (IDP). Once the IWMP is finalised and incorporated into the IDP, ongoing monitoring of performance against the plan is required.

“It is vital to appoint qualified, experienced and professionally recognised experts to guide waste management planning to ensure that IWMPs align with legislation and can be practically implemented,” he concludes.

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Environmental Engineering

Safe travel on Sani Pass

Maccaferri’s retaining walls and erosion measures have provided an engineered solution for a complex road realignment in Lesotho, which also provided the opportunity for community training and skills transfer.

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he upgrade of the Main Road P318 along Sani Pass between Himeville and the Lesotho border has been steadily progressing since construction began on this 14 km route in January 2017. The upgrade includes rerouting and raising the current road sections, as well as the paving thereof, enabling easier pass navigation.

The rerouting and raising of the road required innovative retaining structures to ensure retention of the soil beneath. Furthermore, the lower-lying road sections next to the Mkhomazana River required protection from scour and undermining, particularly in flood conditions.

Maccaferri offered soil retaining and flood mitigation solutions using Terramesh®, gabion and Reno Mattress® structures. These are modular systems used for soil reinforcement. They are composed of pre-assembled units fabricated with double twisted wire mesh 8x10 made of Galfan (Zn-Al alloy) and polymer-coated steel wire. They are produced in compliance with SANS 1580:2010 and EN 10223-3:2013.

The benefits of these solutions at Sani Pass (and in similar environments) include: • Aesthetics: The project required non-invasive options that blended into the existing environment. These solutions maintain the general aesthetic of the surrounding area by appearing as a natural feature of the region.

• Installation: Due to the limited, and difficult, working space on many of the road sections, the installation of concrete using machinery would have proved very difficult. Terramesh, gabion and Reno Mattress units can be placed and filled by hand without using machinery,

allowing for less impact on the traffic up the pass, ensuring the safety of both the contractor and commuters.

• Flexibility: The structures are semi flexible, with a high resistance to longitudinal differential settlement. As such, they allow for a 2% differential settlement, 5% compressibility and ±100 mm on the alignment (SANS 54475-1:2017).

• Job creation: Skilled labour was not required for the installation. Labourers installing the units were able to do so adequately and economically through Maccaferri’s training programme. This allowed for community upliftment through local job creation and negated the need to bring in skilled labourers from outside the area.

• Cost: The use of these solutions significantly reduced the total cost of the project as compared to other solutions (based on cost of rockfill from commercial source).

A section of Terramesh retaining wall

Training As part of Maccaferri’s project services, which included design, supply and project management, continuous site training was also offered. Being a KwaZulu-Natal Department of Transport (DOT) project, falling under the framework and auspices of the Expanded Public Works Programme, this presented a great opportunity for the main contractor, Leomat Construction, to invite local emerging enterprises to subcontract for the erection of the gabion and Terramesh structures.

The construction of gabions is highly labour intensive, and the large volume of gabion works on this project allowed for a greater inclusion of local small to medium enterprises. This resulted in the improvement of the project’s community participation goals and increased the local participation in the construction.

Maccaferri’s on-site training allowed for the labour force to be upskilled, and the continued monitoring during the project life cycle assists in ensuring that the construction is kept in line with the project quality specifications. A total of 60 people have participated in the training and construction of the gabion works.

IMIESA March 2019

41

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Insurance

Engineering and construction insurance in a challenging market Sustaining a business in an economy under prolonged pressure is a challenge. Add the risks associated with the engineering and construction sector, and it’s no surprise that many companies are closing or scaling down, and mining operations are showing contraction.

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ccording to Michael Steensma, senior manager: Engineering at Old Mutual Insure, this situation is largely due to delays in contracts being awarded, as companies go into business rescue owing to the poor economic climate.

“Insurers should expect their clients to downsize portfolios,” he states.

Risks for insurers and the insured The biggest risks for insurers in the engineering and construction sector include contract types, location, and lack of skills – combined with fire, theft (particularly where copper cabling is involved), riots and strikes. “Furthermore, we are moving into an era where climate change is a reality and needs to be considered by the insured and insurers,” says Steensma.

For the insured, the risks include failing to cover free-issue materials in their policies. These are the materials given to the contractor free of charge (not catered for in terms of the bill of quantities) for incorporation into the project and which must be included in the sum insured.

“Some clients forget or fail to insure their surrounding property exposures correctly,” says Steensma. This would cover employers’ property in the care, custody and control of the contractor against damage caused by construction activities.

Another consideration to take into account is covering delays in start-up. “This is available for employer-controlled projects to cover the loss of profits, revenue or rental in the event that the project is not completed in time due to an insurable event such as fire damage,” he says.

Tailored insurance solutions According to Steensma, a tailored insurance solution across a number of lines of business associated with construction projects could mitigate risks. “Our Construction Risks policy provides cover to our customers for their construction projects not only for loss or damage to the works but also the thirdparty losses arising from the performance

of the project, from the time they break ground until the project is completed and handed over. The policy includes the works and liability covers during the defects liability period.”

Future engineering and construction insurance opportunities Steensma sees the increase in infrastructure and housing projects, due to urbanisation, providing key opportunities for insurers.

“Another opportunity would come from replacing of ageing infrastructure (roads and services) and renewable energy.”

To meet these opportunities, the insurance industry needs to innovate and adapt. “One way we have done this is by providing a single product for megaprojects that require cover from the marine stage through to construction and then operational cover, including liability exposures.”

Steensma further suggests increasing the emphasis on actuarial and computerbased risk modeling to better understand and evaluate risk exposures at any stage of a project. “Future clients will expect to do business quicker, easier and more efficiently, promoting the need to review our distribution channels.” He cites the business information modeling process, which is being implemented by the larger construction companies, as a good example.

“An increase in technology could lead to improvements in efficiency and potentially make a risk more attractive,” concludes Steensma.

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Cement & Concrete

Crafting footpaths in sand and mortar Well-constructed walkways have functional, safety and aesthetic benefits.

Br yan Perrie, MD of The Concrete Institute, provides some guidelines on how municipalities with limited budgets can achieve great paving results.

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IMIESA March 2019

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Bryan Perrie, MD of The Concrete Institute

hen installing maintenance-free paving laid with open joints on either a mortar or sand bed, there are a number of factors to consider. The paving materials to choose will depend on cost, design preference and whether a formal or informal effect is required.

Generally, the thicker the units, the stronger the paving will be and the greater the loads it will carr y without distorting.

The finished paving must have a minimum slope of 1:50 for proper drainage, and it must slope away from buildings.

Cement & Concrete

All cement sold in South Africa must meet the requirements of SANS 50197 for common cement or SANS 50413 for masonr y cement and the National Regulator for Compulsor y Standards (NRCS) requirements as detailed in NRCS VC9085. Bags should be clearly marked with the strength grade, notation indicating composition and a Letter of Authority (LOA) number issued by the NRCS. An LOA is issued for each cement type from each source. Note that masonr y cements complying with SANS 50413 are not permitted to be used in concrete.

A simple way of deciding whether a sand specification is suitable for mor tar is to mix 5 kg of cement with 25 kg of airdr y sand and then add enough water to produce a consistency suitable for mortar.

If more than 6 ℓ of water is needed, the sand is unsuitable.

When it comes to recommended laying methods, paving units less than 40 mm thick should always be laid on a bed of mortar to give a total thickness of not less

than 40 mm: thicker units may be laid on a sand bed.

Site preparation In preparing the site, Perrie says the ground below the paving must be firm and stable so that it does not settle unevenly with time. Plus, it must have the same slope as the finished paving.

The best approach is to remove all roots and vegetable matter from the site, and preferably the topsoil. The bed then needs to be trimmed to the correct level and slope. Soft and filled areas must be well stamped down.

“If the fill is ver y dr y, mix in just enough water to dampen it and then compact it,” Perrie explains. “If paving is laid IMIESA March 2019

45

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A strong foundation for infrastructure success

on sand, a kerb should be provided to prevent outward movement.”

Laying procedures “On mortar: mix one part cement with six parts sand until the colour is uniform, then add water slowly. You will need soft mortar – about the consistency of toothpaste,” he continues.

Alternatively, the in situ soil can be stabilised as follows: • by loosening the top 50 mm of soil and then spreading cement at a rate of 1 bag/8 m2 • mixing and adding water until the mix has the consistency of a smooth paste.

“Lay small areas of about 1 m2 at a time. Lay a bed of mortar so that the paving plus mortar will be 40 mm or thicker,” Perrie continues. “The mortar layer thickness should not be less than 15 mm. Place the paving units on the mortar, tap each one down firmly and check that it is level and at the correct slope. The mortar will rise a little into the joint between the units.”

“On sand: spread a layer of loose sand 25 mm thick and level it off. Lay the paving units on this and tap each one firmly into place with, for example, a wooden mallet. Check regularly that the paving is at the correct slope and that the units are correctly lined up.”

Jointing

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With sand, installers should pour dry sand on the surface of the paving and brush it into the spaces between the units. Then water it lightly to wash the sand well down into the joints. The sand stabilises the paving by limiting the movement of the units.

With mortar: for a jointing mortar, mix one part cement thoroughly with four parts sand, then add water slowly and mix to a soft paste. Completely fill the joints with mortar. If the units are laid on a mortar base, the joints should preferably be filled within about two hours of laying the mortar bedding. This will ensure a good bond between the joint and bedding mortars.

Dry sand-cement mix (one part cement, three parts sand) can be brushed over the paving and lightly watered into place provided that the surfaces of the units are smooth enough to ensure that spillage on the surface can be removed entirely. Use a wet cloth or brush to remove any mortar from the top of the paving while it is still plastic; once it has hardened it is difficult to remove.

Where large areas are paved with mortar-filled joints, it is advisable to provide contraction joints at intervals of not more than 2 m. They should be about 10 mm wide, extend right through the paving and be filled with sand.

“Cover paving that has been laid with mortar with wet sacking or plastic sheeting for two or three days so that it does not dry too quickly,” Perrie advises. “Premature drying results in the mortar not developing its full strength and the paving may crack.”

It’s important to add that methods of paving for driveways and other areas that will be used by motor vehicles may differ from the above. “Consult relevant publications before building driveways or other areas that may need to take heavier loads,” Perrie concludes.

Cement & Concrete

Precast as a vocation

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earners at The Gateway School in Roodepoor t are exploring the creative world of concrete, under the guidance of precast manufacturer Caleon Garden Creations.

Through a structured programme, three to four learners are taken in at a time and mentored by Caleon’s management and employees at the company’s Rietfontein factor y. Products produced here include tables, benches, pots and water features.

The Gateway School’s mandate is to help learners with special needs achieve their full potential, developing them holistically. The school often works with external stakeholders and has partnered with Caleon for the past four years. AfriSam

also recently came on board to suppor t this worthy initiative.

Speaking on behalf of The Gateway School, its occupational therapist Karen Botha says the school is touched that there are people who understand its needs and are committed to helping this cause.

“Our continued partnership with Caleon, and now with AfriSam, gives our learners opportunities to learn new skills,” says Botha. “More importantly, it helps them

Under the guidance of Caleon Garden Creations personnel, learners undertake projects and take tremendous pride in their precast creations

build confidence in their abilities and shows them just how much more they are capable of. For that, we are grateful.”

IMIESA March 2019

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Ammann Construction Machinery, Unit 3 Great North Industrial Park, 20 van Wyk Road Brentwood Park, Benoni 1500, South Africa Tel. + 27 11 849 3939, Fax + 27 11 849 8889, info.aza@ammann-group.com For additional product information and services please visit : www.ammann.com MMP-2488-00-EN | © Ammann Group

Transport, Logistics, Vehicles & Equipment

Technology driven Ammann leads through a concerted investment in innovation designed to maximise uptime and lower working costs.

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ithin its product portfolio, Ammann provides a broad range of solutions to deliver class-leading performance across its light equipment range, which is supplied and supported within Southern Africa by ELB Equipment’s dealer network.

Light equipment machines comprise rammers, vibratory plate compactors, walk-behind rollers, add-on compactors and trench rollers.

“We’ve achieved strong gains within South Africa for our asphalt plants, soil and asphalt compactors, and asphalt pavers,” explains Rocco Lehman, general manager, Ammann South Africa. “In 2019, our goal is to gain new ground in the light equipment sector, which has excellent growth potential among both small and large contractors. This will include competitive pricing on light machines when bought in conjunction with our heavier-duty models, such as Ammann tandem rollers.

“We also have a specific strategy for the plant hire market, which includes the development of flexible finance leasing packages. This could include buy-back agreements for low-hour machines, which would create a pool of certified used units, with extended warranties. That will lower the barrier to entry for SMMEs, who tend to be more price-sensitive,” he continues.

www.ammann-group.com

BELOW The ACR 70 diesel poweredrammer is a class leader. This unit weighs 83 kg, has a percussion rate of 12.2 HZ, and a maximum compaction performance of 60 cm

Walk-behind leader Best-sellers in South Africa to date include the Ammann ARW 65 walk-behind roller, which is a dual-amplitude machine, making it highly versatile on-site. The operator can choose whether to utilise a high-amplitude setting for work on gravel/soil, or a low-amplitude setting for asphalt and bituminous materials.

Two petrol-driven rammer models are available locally, namely the ATR 60 and ATR 68. Amman also fields the ACR 70 dieselpowered rammer. “A number of contractors prefer the ACR 70, since the balance of their

LEFT The ARW 65 has an approximate operating weight of 719 kg and a drum width of 650 mm. The machine delivers a maximum vibration frequency of 60 Hz and a maximum centrifugal force of 11/21 kN

earthmoving and allied fleet runs on diesel,” explains Craig Sheppard, national product manager, ELB Equipment.

The add-on compactor range provides further versatility when compacting in hard-to-reach places like deep, narrow trenches and steeper grades. Fitted to an excavator arm, these addons also provide more power than most other compaction options in these applications.

In turn, Ammann’s trench rollers provide a more specialised compaction solution and the OEM remains the only manufacturer currently offering both articulated and skidsteered versions.

Hydrostatic plate compaction Within the plate compactor segment, Ammann produces an extensive line, starting at an operating weight of around 54 kg and extending up to 778 kg. Based on local demand in this class, ELB Equipment currently supplies the APH Series. This is a fully hydrostatic, reversible vibratory plate compactor range equipped with unique technological features. On top-end models, these include Ammann’s triple-shaft exciter system, which boosts performance and climbing ability, while making the machine more responsive and easier to turn.

Ammann pioneered the development of hydrostatic walk-behind rollers and has subsequently transferred this technology to other products, like the APH. As opposed to mechanically driven systems, hydrostatic operation significantly simplifies maintenance and provides unsurpassed operator control.

“Since ELB Equipment was appointed as the Ammann dealer some five years ago, we’ve seen a progressive roll-out of our full solution, thanks to excellent service and after-sales support. The focus on further expanding our light equipment range this year is an exciting development for the market,” Lehman concludes.

14 Atlas Road Anderbolt, Boksburg, 1459 Tel: +27 (0)11 306 0700

IMIESA March 2019

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Transport, Logistics, Vehicles & Equipment

Wacker Neuson’s EZ17e is the first e-powered mini excavator to go into production

e-Power evolution Wacker Neuson is renowned globally for its class leadership position in light and compact equipment solutions. IMIESA speaks to Rainer Schmidt, product manager at Wacker Neuson South Africa, about key developments within its diverse line-up. These include lithium-powered machines that are world firsts. By Alastair Currie

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dvancements in lithiumion batter y technology have revolutionised many areas of industry, including motorspor t, where electric-powered (e-powered) motorcycles now compete on the international GP circuit, producing outputs similar to their carbon-fueled counterparts. So it’s not surprising that the construction sector is following suit – a case in point being the pioneering work undertaken by Wacker Neuson’s research and development (R&D) teams.

Batter y-powered machines in the Wacker Neuson zero-emission range include rammers, plate compactors, trackdumpers, articulated and all-wheel steer loaders, and mini excavators. The AS60e rammer and the AP2560e vibratory plate compactor are recent additions, alongside the 1.5 t EZ17e mini excavator and DW15e wheel dumper.

“We understand that these e-powered machines are competing against petrol and/or diesel power, so our designs are field-proven to ensure that they meet the same or similar performance standards,”

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IMIESA March 2019

explains Schmidt. “In most instances, a single battery charge suffices for an average day’s work. Another plus is that these batteries are designed to be interchangeable with other Wacker Neuson units. Plus e-powered machines are emission-free, virtually maintenance-free, and provide a saving of up to 55% in energy costs.”

Three batter y-driven rammers are available: the mid-range AS50e is sold locally and is proving popular with contractors and plant hire companies.

The new AS60e is now the flagship model.

The AS50e’s BP1000 battery takes 80 minutes to charge and provides 30 minutes of consistent power. Wacker Neuson will also be releasing a longer-life battery, the BP1400, which lasts around 40 minutes following an approximately 90-minute recharge.

Within the e-powered plate compactor lineup, the model chosen for the Southern African region is the AP1850e (the first two numbers stand for 18 kN and the second two for 50 cm working width).

Approximately two hours of operation can be achieved on a single battery charge.

Rise of the mini excavator Wacker Neuson’s design philosophy is driven by the ‘voice of the customer’, which heavily influences its R&D programme and expanding conventional and e-powered product line strategy.

South Africa’s mini excavator population is still relatively small, but is expected to grow as customers begin to appreciate the high power-to-weight-ratio The AS50e has an operating weight of 70 kg and delivers a maximum percussion rate of 680 blows/minute. The ramming shoe size is 330 mm x 280 mm

Transport, Logistics, Vehicles & Equipment capabilities provided by these compact machines. Driving down costs is another major factor, as fleet owners look for more fuel-efficient machines that can multitask.

Wacker Neuson currently offers a comprehensive mini excavator range in the 1.5 t, 2 t, 2.5 t, 3.5 t and 5 t class. Strong growth locally is anticipated within the 5 t to 6 t segment for diverse industries that include agriculture, construction and mining. The introduction of a 6 t Wacker Neuson model is at an advanced stage of development, and will further bolster the OEM’s leadership position. In the meantime, the EZ17e is the first e-powered mini excavator to go into production.

The AP1850e plate compactor

Compaction news A new development is Wacker Neuson’s entry into the heavy compaction class to meet customer demand for a full solution.

The OEM is famous for its compact rideon tandem rollers, starting with the RD12 1 t series and extending up to the flagship RD45 range, which tops out at around 4.4 t, including rollover protection structure.

This product offering has now been expanded with the addition of the Wacker Neuson

RC110 (10 t), RC120 (11 t) and RC190 (20 t) smooth drum rollers for the South African market.

“We cater for the traditional market and new adopters, and continue to expand our niche offerings accordingly. As batterypower technology advances, this will certainly play a greater role across all our product classes,” he continues.

“Whether electric, petrol or diesel powered, every machine is purpose-designed to provide the lowest cost of ownership. Naturally, that makes after-sales service a key focus.

This is underscored by the fact that even after a model has been discontinued, we still guarantee parts availability for 10 years. That’s our commitment to long-term customer relationships.”

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Paving the Way

Power and efficiency Geared towards lower total cost of ownership, Mercedes-Benz’s new Arocs truck range is targeting niche growth in the distribution and construction sectors.

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T

he Mercedes-Benz Arocs series is powered by the same OM460 Euro III 12.8 litre engine installed on the new long-haul Actros series sold into the Southern African market, with drive provided by the OEM’s PowerShift 3 automated transmission.

Two Arocs distribution models will be launched in the first phase: the Arocs 2636L/57 6x2 and the Arocs 3345/48.

Initially, customers will have a choice between either a 265 kW (360 hp) or 330 kW (450 hp) power plant. Both come standard with a one-year/unlimited km complete vehicle warranty and a five-year/650 000 km standard warranty on the powertrain.

The construction line will also kick off with two models: the Arocs 3336K/36 tipper chassis and the Arocs 3236B/51 8x4 mixer chassis, both powered by a 265 kW output OM460 Euro III engine. Additional engine outputs are planned going for ward.

The Arocs 3236B/51 features a weightoptimised hypoid rear axle, as well as a lightweight aluminium fuel tank, disc brakes and aluminium rims to reduce kerb weight and increase payload. This enables the 8x4 mixer chassis to supply 8 m3 of ready-mixed concrete on ever y trip. The overall gross vehicle mass is approximately 35 tonnes.

Next in line, the Arocs 3336K/36 has been designed with a short rear overhang

Transport, Logistics, Vehicles & Equipment

The Arocs range can be reconfigured to a wide range of tasks within the construction and distribution segments

featuring robust planetar y axles, a double disc clutch, robust drum brakes optimised for off-road use and a 16-speed PowerShift 3 automated transmission. The Off-Road Drive programme is standard.

The new Arocs for construction is sold with a one-year/ unlimited km complete vehicle warranty and a three-year/ 250 000 km/5 000 hour standard warranty on the powertrain.

Market developments “The second half of 2018 saw a rebound in truck sales, particularly in the long-haul segment and, although the construction sector remains subdued, we expect conditions to improve here over the next 12 months,” comments Jasper Hafkamp, CEO, Daimler Trucks & Buses Southern Africa.

Since the introduction of the new Actros around May last year, more than 2 000 orders have been placed, which underscores the market’s confidence in the product. Actros models are now available with either Euro III or Euro V engines. So far, more than 100 Euro V models have been sold, indicating a willingness by South African consumers to invest in energy-efficient and ecofriendly technologies. Mercedes-Benz is the current South African market leader in long-haul.

“Traditionally, Mercedes-Benz has always been a strong contender in construction and distribution, and we recognised the need to find new solutions to take the brand to the next level,” says Maretha Gerber, head of Mercedes-Benz Trucks South Africa.

As with the Actros range, the Arocs line-up offers higher levels of fuel efficiency than previous-generation units. Within construction and distribution fleets, fuel represents between 30% to 50% of the total cost of ownership; for long-haul, that figure is much higher, at around 62%. As fuel costs rise, adopting technologies like advanced driveline set-ups that pass on savings becomes even more critical. The driveline fitted on the Actros and Arocs is field-proven, having undergone some 16 million km of testing on South African roads.

IMIESA March 2019

53

“We are confident that Arocs customers within the distribution segment will experience a 3% to 5% saving, depending on the application,” adds Gerber.

Extended ser vice inter vals will also prove attractive for Arocs customers: up to 50 000 km in the distribution environment, and 35 000 km within the construction space. Combined with routine maintenance and focused driving, that will translate into more time on the road.

Building Materials

Cutting carbon emissions South Africa is the largest CO2 emitter in Africa and the 12th largest in the world. The Switch Africa Green Project is attempting to help address this by suppor ting sustainable building materials.

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he South African clay brick sector, which produces more than 3.5 billion clay bricks per year, has committed to playing its part in meeting government’s targets to reduce carbon emissions.

The industry’s sustainability initiatives are being driven by the Clay Brick Association of South Africa (CBA). Over the last five years, the CBA’s Energy Efficient Clay Brick Programme has resulted in a 10% to 15% reduction in the industry’s greenhouse gas emissions.

Switch Africa Green In 2018, the CBA was commissioned to execute a three-year plan, co-sponsored by the EU, under the Switch Africa Green Project.

“Switch Africa Green encompasses several integrated industry initiatives to support, promote and implement sustainable development in the sector,” reports Mariana Lamont, executive director, CBA. “Our project plan includes research on improving sustainability in production, as well as educating construction professionals, government and homeowners on how to design resourceefficient buildings.”

By reviewing and assessing lessons learned in the European clay brick sector, CBA is able to provide

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IMIESA March 2019

The CBA is working with its members to conduct training courses and distribute educational materials, giving informal brick makers the skills needed to operate more sustainably and profitably

The Local Economic Development offices at several municipalities have shown interest in engaging with the project and the informal sector.

internationally proven, locally relevant fact sheets on green building practices, promoting continuous environmental and sustainability improvements in the local industr y.

A key topic for CBA members is reducing CO 2 emissions. To achieve a real drop in CO2 emissions, CBA members need to improve or upgrade their production facilities.

CBA members are currently collaborating on a range of pilot projects that improve the sustainability of their operations. An online data gathering and reporting portal has been developed. This will track nine sustainability metrics, which will help to identify the most effective energy-saving methods and technologies.

“The Clay Brick Association of Southern Africa has led research in brick production and brick building design for 55 years,” says Lamont. “This information aids architects and engineers to maximise thermal comfort and energy efficiency in residential and commercial buildings.”

Transforming the formal sector

Developing the informal sector The Switch Africa Green Project promotes an exchange of ideas between formal and informal brick producers, sharing practical ways to reduce coal and water consumption, air pollution and waste.

A four-day pilot training session held in Indwe in the Eastern Cape was attended by 24 informal clay brick makers. Conducted in English, Afrikaans and isiXhosa, the training was well received by both the informal brick makers as well as the municipality, and additional courses are being developed.

PROFESSIONAL AFFILIATES AECOM siphokuhle.dlamini@aecom.com Afri-Infra Group (Pty) Ltd banie@afri-infra.com ALULA (Pty) Ltd info@alulawater.co.za AQUADAM (Pty) Ltd sales@aquadam.co.za Aurecon Fani.Xaba@aurecongroup.com Aveng Manufacturing Infraset werner.booyens@infraset.com Averda claude.marais@averda.com Bigen Africa Group Holdings otto.scharfetter@bigenafrica.com BMK Group brian@bmkgroup.co.za Bosch Munitech info@boschmunitech.co.za Bosch Projects (Pty) Ltd mail@boschprojects.co.za BVI Consulting Engineers marketing@bviho.co.za Civilconsult Consulting Engineers mail@civilconsult.co.za Corrosion Institute of Southern Africa secretary@corrosioninstitute.org.za Development Bank of SA divb@dbsa.org.za DPI Plastics Farhana@dpiplastics.co.za EFG Engineers eric@efgeng.co.za Elster Kent Metering Leonardus.Basson@honeywell.com ERWAT mail@erwat.co.za Fibertex South Africa (Pty) Ltd rcl@fibertex.com GIBB yvanrooyen@gibb.co.za GIGSA secretary@gigsa.org GLS Consulting nicky@gls.co.za Gudunkomo Investments & Consulting info@gudunkomo.co.za Hatch Africa (Pty) Ltd info@hatch.co.za Henwood & Nxumalo Consulting Engineers (Pty) Ltd pmboffice@hn.co.za Herrenknecht schiewe.helene@herrenknecht.de Huber Technology cs@hubersa.com Hydro-comp Enterprises dan@edams.co.za I@Consulting louis_icon@mics.co.za INGEROP mravjee@ingerop.co.za Integrity Environment info@integrityafrica.co.za IQHINA Consulting Engineers & Project Managers info@iqhina.co.za iX engineers (Pty) Ltd hans.k@ixengineers.co.za JBFE Consulting (Pty) Ltd issie@jbfe.co.za JG Afrika DennyC@jgafrika.com KABE Consulting Engineers info@kabe.co.za Kago Consulting Engineers kagocon@kago.co.za Kantey & Templer (K&T) Consulting Engineers info@kanteys.co.za Kitso Botlhale Consulting Engineers zimema.jere@gmail.com Lektratek Water general@lwt.co.za Lithon Project Consultants (Pty) Ltd info@lithon.com Makhaotse Narasimulu & Associates mmakhaotse@mna-sa.co.za Malani Padayachee & Associates (Pty) Ltd admin@mpa.co.za M & C Consulting Engineers (Pty) Ltd info@mcconsulting.co.za Maragela Consulting Engineers admin@maragelaconsulting.co.za Marley Pipe Systems info@marleypipesystems.co.za Martin & East gbyron@martin-east.co.za

Masithu Consulting & Project Management info@mcpm.co.za Mhiduve adminpotch@mhiduve.co.za Mogoba Maphuthi & Associates (Pty) Ltd admin@mmaholdings.co.za Moedi Wa Batho Consulting Engineers (Pty) Ltd info@wabatho.co.za Much Asphalt bennie.greyling@muchasphalt.com NAKO ILISO lyn.adams@nakogroup.com Nyeleti Consulting ppienaar@nyeleti.co.za Odour Engineering Systems mathewc@oes.co.za Pumptron info@pumptron.co.za Ribicon Consulting Group (Pty) Ltd info@ribicon.com Royal HaskoningDHV francisg@rhdv.com SABITA info@sabita.co.za SAFRIPOL mberry@safripol.com SALGA info@salga.org.za SAPPMA admin@sappma.co.za / willem@sappma.co.za SARF administrator@sarf.org.za.co.za SBS Water Systems mava@sbstanks.co.za Sembcorp Siza Water info-sizawater@sembcorp.com Sigodi Marah Martin Management Support lansanam@sigodimarah.co.za SiVEST SA garths@sivest.co.za Sizabantu Piping Systems (Pty) Ltd gregl@sizabantupipingsystems.com SKYV Consulting Engineers (Pty) Ltd kamesh@skyv.co.za SMEC capetown@smec.com SNA stolz.j@sna.co.za Sobek Engineering gen@sobek.co.za Southern African Society for Trenchless Technology director@sasst.org.za Southern Pipeline Contractors (Pty) Ltd spc@vinci-construction.com SRK Consulting jomar@srk.co.za STAR OF LIFE EMERGENCY TRADING CC admin@staroflife.co.za Syntell julia@syntell.co.za TECROVEER (Pty) Ltd info@tecroveer.co.za TPA Consulting roger@tpa.co.za Ulozolo Engineers CC admin@ulozolo.co.za UWP Consulting nonkululekos@uwp.co.za V3 Consulting Engineers (Pty) Ltd info@v3consulting.co.za south-africa@vetasi.com Vetasi VIP Consulting Engineers esme@vipconsulting.co.za VUKA Africa Consulting Engineers info@vukaafrica.co.za Water Institute of Southern Africa wisa@wisa.org.za WAM TECHNOLOGY CC support@wamsys.co.za Water Solutions Southern Africa ecoetzer@wssa.co.za Wilo South Africa marketingsa@wilo.co.za WRP ronniem@wrp.co.za WRNA washy@wrnyabeze.com WSP Group Africa ansia.meyer@wsp.com

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