IMIESA August 2020

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

I N F R A S T R U C T U R E D E V E LO P M E N T • R O A D S • B U I L D I N G • M A I N T E N A N C E • S E R V I C E D E L I V E R Y

M&D Construction Group At the cutting-edge of municipal infrastructure delivery

Roads & Bridges Bridges that glow in the dark

Water & Wastewater Virtual audits hold new opportunities

Bitumen & Asphalt Pavement design and construction

Municipal Focus Eastern Cape metros

IN THE HOT SEAT The utilisation of automated road assessments ensures objectivity, accuracy and an exceptionally high degree of repeatability in a fraction of the time when compared to conventional methods.”

Yeshveer Balaram General Manager, ARRB Systems Africa ISSN 0257 1978

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INSIDE

VOLUME 45 NO. 08 AUGUST 2020

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MUNICIPAL FOCUS

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www.infrastructurenews.co.za

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

I N F R A S T R U C T U R E D E V E LO P M E N T • R O A D S • B U I L D I N G • M A I N T E N A N C E • S E R V I C E D E L I V E R Y

M&D Construction Group At the cutting-edge of municipal infrastructure delivery

Roads & Bridges Bridges that glow in the dark

INSIDE

Regulars Editor’s comment

3

President’s comment

5

Index to advertisers

63

Bitumen & Asphalt

Pavement design and construction

Municipal Focus Eastern Cape metros

IN THE HOT SEAT

Cover Story At the cutting-edge of municipal infrastructure delivery

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The utilisation of automated road assessments ensures objectivity, accuracy and an exceptionally high degree of repeatability in a fraction of the time when compared to conventional methods.”

Yeshveer Balaram General Manager, ARRB Systems Africa ISSN 0257 1978

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ON THE COVER M&D Construction Group, a leading multidisciplinary construction company, continues to build on an impressive track record of successfully completing technically complex infrastructure projects for South African municipalities and other client bodies operating at local government level. P6

IN THE HOT SEAT Maintaining and preserving South Africa’s paved and gravel road network is crucial for society and the economy.

Yesh Balaram, general manager, ARRB Systems Africa, discusses how ARRB’s technologies are redefining automated road assessments. P8

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ROADS & BRIDGES Bridges that glow in the dark

42

Niche infrastructure delivery

53

Reindustrialising Buffalo City

43

Civil suite software

55

Tapping the Coegakop wellfield

46

Achieving water security through 4IR

49

Roads to economic growth

56

Bridging communities

57

Power by design

59

Water & Wastewater Wise spring water use is essential 31

Water & Wastewater Virtual audits hold new opportunities

Tackling the drought

Hot Seat Intelligent pavement management and big data

8

Winning through remote teamwork 10

Bridges that glow in the dark Franki supports the Great River Bridge in Mauritius

Bosch Munitech works towards a sustainable future

37

Project management – the key to service delivery

38

Pressure reduction solution

Tackling the drought

42

14

Reindustrialising Buffalo City

43

18

Tapping the Coegakop wellfield

46

Achieving water security through 4IR 49 20 22

Building Systems Schools built with bricks

24

Gabion architecture

26

Niche infrastructure delivery

53

Civil suite software

55

Roads to economic growth

56

Bridging communities

57

Power by design

59

Waste Management How to extend the life of your landfill

Cement & Concrete The role of glass and steel fibres in concrete

28

Legal

Carbon fibre reinstates Saldanha Bridge

30

PPPs – the benefits and obstacles to success

26

BUILDING SYSTEMS Gabion architecture

40

Nelson Mandela Bay & Buffalo City

Stormwater & Urban Drainage Permeable paving is not porous

34

12

Roads & Bridges The power of geosynthetics

32

Ensuring SA’s water security

Pumps & Valves

Bitumen & Asphalt The right way to design and construct surface treatments

Virtual audits hold new opportunities

34

60

62

WATER & WASTEWATER Ensuring SA’s water security

IMIESA August 2020

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@boschholdings

EDITOR’S COMMENT MANAGING EDITOR Alastair Currie SENIOR JOURNALIST Danielle Petterson HEAD OF DESIGN Beren Bauermeister CHIEF SUB-EDITOR Tristan Snijders CONTRIBUTORS Roger Feldmann, Randeer Kasserchun, Samantha Naidoo, Bryan Perrie, Natalie Reyneke, Gerrie van Zyl, Leslie van Zyl-Smit PRODUCTION & CLIENT LIAISON MANAGER Antois-Leigh Nepgen PRODUCTION COORDINATOR Jacqueline Modise GROUP SALES MANAGER Chilomia Van Wijk FINANCIAL MANAGER Andrew Lobban BOOKKEEPER Tonya Hebenton DISTRIBUTION MANAGER Nomsa Masina DISTRIBUTION COORDINATOR Asha Pursotham SUBSCRIPTIONS subs@3smedia.co.za PRINTERS Novus Print Montague Gardens +27 (0)21 550 2300 ___________________________________________________ ADVERTISING SALES KEY ACCOUNT MANAGER Joanne Lawrie Tel: +27 (0)11 233 2600 / +27 (0)82 346 5338 Email: joanne@3smedia.co.za ___________________________________________________

PUBLISHER Jacques Breytenbach 3S Media 46 Milkyway Avenue, Frankenwald, 2090 PO Box 92026, Norwood 2117 Tel: +27 (0)11 233 2600 www.3smedia.co.za ANNUAL SUBSCRIPTION: R600.00 (INCL VAT) ISSN 0257 1978 IMIESA, Inst.MUNIC. ENG. S. AFR. © Copyright 2020. All rights reserved. ___________________________________________________ IMESA CONTACTS HEAD OFFICE: Manager: Ingrid Botton P.O. Box 2190, Westville, 3630 Tel: +27 (0)31 266 3263 Email: admin@imesa.org.za Website: www.imesa.org.za BORDER Secretary: Celeste Vosloo Tel: +27 (0)43 705 2433 Email: celestev@buffalocity.gov.za EASTERN CAPE Secretary: Susan Canestra Tel: +27 (0)41 585 4142 ext. 7 Email: imesaec@imesa.org.za KWAZULU-NATAL Secretary: Ingrid Botton Tel: +27 (0)31 266 3263 Email: imesakzn@imesa.org.za NORTHERN PROVINCES Secretary: Ollah Mthembu Tel: +27 (0)82 823 7104 Email: np@imesa.org.za SOUTHERN CAPE KAROO Secretary: Henrietta Olivier Tel: +27 (0)79 390 7536 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 Email: imesafsnc@imesa.org.za 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. _____________________________________________

Data accuracy shapes our destiny

O

ver the last six months, we’ve experienced pandemic modelling scenarios on an unprecedented scale.

Fortunately for South Africa, our >84% Covid19 recovery rate far exceeded best scenario predictions. Local and global stock markets also didn’t plunge to the levels forecasted, and gold breached US$2 000 (R33 700) per ounce.

Financial markets are always going to be influenced to some extent by variable factors – emotion and subjectivity being two key ones.

However, the best executed plans and forecasts still depend on the most accurate available data to achieve some degree of statistical certainty.

Most countries, including South Africa, have an act relating to statistics, which authorises governments to collect and analyse socioeconomic data.

It will never be perfect, and that’s true for the best-case examples from the developed and developing worlds. However, this forms the basis for informed decisions, reinforced by experience and an in-depth analysis of historical trends.

For this reason, investing in statistical agencies is vital, especially for South Africa, where the information and infrastructure gaps keep growing.

We need greater clarity and urgent answers.

Informal settlement trend This is particularly true for South Africa’s informal settlements. Covid-19 highlighted the obvious water and sanitation issues, as well as the absolute right to safe and secure shelter. However, the escalation in land invasions during the lockdown was unexpected.

Was it exacerbated by an economic displacement from formal to informal? Or an escalating urban migration from collapsing rural economies?

Additionally, what percentage of the homeless seeking shelter were South African citizens, as opposed to illegal residents? Without accurate statistics, these questions remain unanswered, and that’s a major concern since funding requirements and budgets depend on verified data.

They also require an accurate population census.

Armed with the right information, we can better prioritise spending in key areas like health, education, housing, water and sanitation, and align them more realistically with national development goals that create employment.

So far, the Auditor-General’s reports show that many municipalities are out of control.

That needs to change within the next financial year. To make it happen, we need exact records of expenditure and proven return on investment as a basis for future budget and grant allocations.

Then we need per formance management systems in place that can be tracked effectively. We also need to ensure that the materials and construction techniques employed meet the highest standards.

Going forward, ratepayers and investors will expect a much higher standard.

Alastair @infrastructure4

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ction Group M&D Construng-e dge of At the cutti ery structure deliv municipal infra

Roads & Bridges

Bridges that glow in the dark

Water & Wastewater hold

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The last door-to-door census was completed in October 2011, where the resulting population estimate was approximately 51.8 million. The next official census will be held between February and March 2021. In the interim, estimates place the 2019 population at around 58.7 million.

That’s in line with South Africa’s actual birth and death statistics.

Khayelitsha (‘our new home’ in Xhosa) in Cape Town was estimated to be home to some 392 000 residents during the 2011 census. Can we confirm the true number in 2021? We need to, so that we can ensure the best service delivery solutions are implemented for one of South Africa’s fastest growing township populations.

Current estimates, factoring in formal and informal settlements in Khayelitsha, now put the number at well over 1 million. The same equally applies when determining the numbers for all informal communities across South Africa.

Virtual audits new opportun ities

Bitumen & Asphalt

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 Joanne Lawrie on +27 (0)82 346 5338.

Pavemen t design and construct ion

Muni cipal Focus metros Eastern Cape

IN THE HOT SEAT automated road assessments ensures objectivity, y in a The utilisation of degree of repeatabilit exceptionall y high methods.” accuracy and an to conventiona l when compared fraction of the time ARRB Systems Africa General Manager, Yeshveer Balaram 0 • 8 ISSN 0257 197

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IMIESA August 2020

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Watch this space for future announcements!

IMPORTANT NOTICE: Due to the global Covid-19 pandemic, this year's 84th IMESA Conference has been postponed by the organisers until October 2021.

Watch this space for future announcements!

CONFERENCE ENDORSED BY

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IMESA ORGANISER

THE INSTITUTE OF MUNICIPAL ENGINEERING OF SOUTHERNÂ AFRICA (IMESA) TEL: 031 266 3263 DEBBIE OR MELANIE

PRESIDENT’S COMMENT

IMESA

Infrastructure is a sound investment

Across the world, regional economies are slowly regaining momentum as we move through and past what is hopefully the worst of the Covid-19 storm.

For developing countries like South Africa, our road to recovery will be a bit steeper, but manageable with the support and coordination of public and private sector investors.

T

he South African Reser ve Bank will be central to this process in maintaining interest rates at attractive levels for foreign direct investors. Then at the implementing end, National Treasur y is on the critical path in prioritising and approving municipal budgets and grants.

The US$1 billion (≈R17 billion) Covid-19 Emergency Programme Loan received in June 2020 from the New Development Bank (NDB) will go a long way in mitigating the health and socio-economic fallout in South Africa. Similar NDB packages have also been approved for India and China.

Added to this is the R70 billion loan from the International Monetar y Fund. The purpose is to help meet South Africa’s

urgent balance of payment needs flowing from the Covid-19 crisis and to implement growth-enhancing structural reforms.

Metro loans Major loans are now also starting to filter through to the metros via the Development Bank of Southern Africa (DBSA). At the end of July 2020, the DBSA announced the approval of a R3 billion development loan for the City of Johannesburg, and a R1.5 billion loan for the City of Tshwane.

It’s significant to note that both metros qualified because they had the in-house municipal engineering capabilities and resources to execute capital projects.

These loans, which will be repaid over a period of 15 to 20 years, are directly intended for infrastructure and related community upliftment projects, with housing being a clear priority to reduce the growing number of informal settlements.

In addition to new works, there’s a strong focus on maintaining and upgrading essential ser vices. As a further plus, the DBSA estimates that some 10 000 jobs will be created.

public and private sector financing will make the Infrastructure Fund a ver y welcome reality. So far, government has committed to some R100 billion over the next 10 years, with provision for R10 billion during the current medium-term expenditure framework.

On the roads front, Sanral is poised to release major new works into the industr y across South Africa. During the current financial year, R7.3 billion worth of projects have been awarded to date, out of a potential shovel-ready total of R30.2 billion.

In the meantime, let’s hope that the worst of Covid-19 is behind us and South Africa can shortly move on to Level 1 of the lockdown. For the construction sector, the prospect of spearheading an infrastructure-led economic recover y is an exciting one.

Infrastructure Fund developments In August 2020, the DBSA’s mandate in terms of government’s Infrastructure Fund initiative was formalised following the signing of a memorandum of agreement with the Department of Public Works and Infrastructure, and National Treasur y.

The DBSA will be instrumental in ensuring that ‘shovel ready’ projects are bankable.

From there, a blended combination of

Randeer Kasserchun, president, IMESA

IMIESA August 2020

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COVER STORY

At the cutting-edge of municipal infrastructure delivery M&D Construction Group, a leading multidisciplinary construction company, continues to build on an impressive track record of successfully completing technically complex infrastructure projects for South African municipalities and other client bodies operating at local government level.

The extensive 18 month long contract for the establishment of the Koster WWTW entailed 20 ha of site clearance and 45 000 m³ of earthworks, in addition to the placement of 2 460 m³ of structural concrete and the construction of 6 760 m2 of block paved roads

H

anded over to the Kgetleng Local Municipality, with all tie-ins completed within the contractual schedule in 2019, the Koster Wastewater Treatment Works (WWTW) stands out as yet another sound example of the contractor’s focus on its core values of ‘being safe’, ‘doing it right’, ‘finding the best way’ and ‘doing what we say’. These are closely aligned to those of Magalies Water,

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IMIESA August 2020

for whom the project was undertaken, as well as other clients tasked with delivering essential municipal services to their constituents.

The scope of construction work for the 6 Mℓ WWTW included an inlet, combined settlement and reactor structure, clarifier, chlorine contact tank, and concrete-lined balancing dam. This is in addition to interconnecting pipework. The latter comprised unplasticised polyvinyl chloride pipes with a maximum diameter of 500 mm and

a 9.5 km long sewer outfall pipeline between various connection points in Kgetleng township and the new sewage treatment plant.

As part of the contract, M&D also constructed a blower house, administration building and recirculating aquaculture system pump station, as well as an access road that consisted of conventional layerworks with an interlocking paving finish and kerbs on both sides.

While this R108 million contract was awarded to the company through an open tender process, M&D’s long professional relationship with Magalies Water and its previous stellar performance on other public sector projects in the province were also very strategic competitive advantages when tendering for the work.

“Certainly, our extensive experience in the water sector, especially in constructing WTWs and WWTWs, also contributed towards M&D being selected as Magalies Water’s preferred contractor for this project,” says Niekie Wagener, head: Infrastructure, M&D. “Executed by M&D’s Infrastructure Division, with support from the company’s fittings factory, the strong team allocated to this contract was also involved in successfully completing the Vaalkop WTW and the Vryburg WWTW in recent years,” he continues.

Niche sectors M&D, a true multidisciplinary construction company, comprises the following divisions: Infrastructure • Civils • Surface infrastructure for mining • Water retaining structures • WTWs and WWTWs • Roads and earthworks • Specialised industrial and marine infrastructure Pipelines • Water, sewer and stormwater • Gas and petrochemical • Plant pipework Oil and Energy • Constructing and upgrading fuel depots • Petrochemical infrastructure • Building specialised tanks • Solar, wind and liquid natural gas projects Special Projects • Forming strategic partnerships with specialists to offer clients significant value. Examples include independent water producer off-

COVER STORY balance-sheet infrastructure on a ‘pay-as-yougo’ basis and new technology-based solutions to solve critical issues in the water sector • Design and build offerings for the construction of education, healthcare and social housing developments • Public-private partnerships • Structural steel and platework • Electrical and instrumentation • Deconstruction.

Notably, the company’s fittings factory in Kya Sands was one of the first contractor workshops to be certified to ISO 3834 quality standards by the South African Institute of Welding, the International Standards Organisation’s authorised national body for company certification.

Ingredients for success The Koster WWTW serves as a prime example of the way M&D plans and executes projects to ensure the highest possible standards of workmanship. Importantly, the company wanted to make ample use of the opportunity that this project provided to expose its many young engineers to a broad spectrum of civil engineering operations.

One of M&D’s strengths is that it has a strong balance between young and seasoned staff. Young construction professionals have an opportunity to be groomed into a successful career in construction by their more experienced counterparts to introduce fresh thinking and ensure business continuity.

Among the young M&D team members who benefited immensely from the extensive training undertaken on this project was Nomsa Tshiitamune, a previously disadvantaged woman engineer promoted to the position of site manager. This supports the company’s ongoing drive to ensure transformation in the South African construction sector as a Level 1 BBBEE contractor, with greater than 51% black and significant black woman ownership levels.

The project also proved to be a very suitable training ground for the many locals who were employed, as well as the more than 15 subcontractors appointed by M&D to complete parts of the work scope. This included the various buildings – the largest component of the project outsourced to emerging contractors – as well as the earthworks, layerworks, concrete paving and kerbs for the access road, which was designed right from the outset to ensure maximum participation by SMMEs.

Nurturing SMME development Notably, M&D recently stepped up their focus on developing SMMEs in the construction sector, with its Khula Nathi platform set to be launched to assist and develop struggling smaller companies to still participate in the economy and create

jobs after the Covid-19 crisis. In so doing, the contractor continues its long legacy, serving as a ‘bigger brother’ to smaller companies in the construction sector, particularly within the communities where it operates.

This culture enshrined in the company’s motto of Khula Nathi (‘grow with us') continues to make a significant contribution towards the successful completion of the company’s projects. For example, there was not a single work stoppage on the Koster WWTW project site due to the excellent rapport that was established with community members right from the outset.

This approach was complemented by excellent team dynamics between the contractor, engineer, employer and the local council as the first point of contact with community members.

Importantly, due consideration also had to be given to the significant pace of construction activities at Koster. This extensive undertaking, involving 20 ha of site clearance and 45 000 m³ of earthworks, in addition to the placement of 2 460 m³ of structural concrete and the construction of 6 760 m2 of block paved roads, had to be completed within 18 months.

The team had to be able to apply innovative thinking to solve an array of challenges, including the extremely rocky terrain over which the full length of the pipeline travelled. All of this had to be done while ensuring the required gradient of the sewer pipeline was maintained.

The scope of construction for the 6 Mℓ WWTW included an inlet, combined settlement and reactor structure, clarifier, chlorine contact tank, and a concrete-lined balancing dam

The ability to establish direction, execute plans and deliver results on all of M&D’s projects is also facilitated by the Murray & Dickson Operating System

MDOS ensures alignment The ability to establish direction, execute plans and deliver results on all of M&D’s projects is also facilitated by the Murray & Dickson Operating System (MDOS). MDOS is based on a tried-and-tested entrepreneurial operating system that promotes accountability throughout the group to ensure that all employees are aligned to core values and pulling in the same direction. It also facilitates a system whereby issues that arise are identified, discussed and solved by identifying the root cause of the issue quickly.

The sensitive location of the Koster WWTW construction site was also another major challenge. Working in a township area, detailed control systems had to be implemented to ensure the safety of community members, especially with regard to the deep open trenches.

“The exceptionally high safety track record that we maintained throughout the project stands out as one of many highlights for the entire professional team. Notably, there was not a single lost-time injury on this contract – testament to the efficacy of our strict health and safety protocols,” says Juan Venter, construction manager, M&D. Rukesh Raghubir, CEO, M&D, says that this project has again demonstrated why the

company continues to grow its share of projects driven by local government.

“Similar to its counterparts in other municipal jurisdictions of the country, Magalies Water is driven by high service levels and on-time project delivery. At the same time, these clients encourage active participation by the local community on all their capital expenditure programmes, as direct labour and through subcontracting portions of the work scope to competent SMMEs. As such, training is an important part of their social investment. By leveraging our own training drive, their investment into infrastructure has benefited many communities in poor areas of the country during the construction phases,” he explains.

“We are certainly very proud of our long legacy of helping local government bodies deliver essential services to South Africans,” Raghubir concludes.

www.mdconstruction.co.za

IMIESA August 2020

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HOT SEAT

At the centre of ARRB’s pavement data collection operation is the ASTM E-1656 compliant Network Survey Vehicle fleet

Intelligent pavement management and big data Maintaining and preser ving South Africa’s paved and gravel road network is crucial for society and the economy. IMIESA speaks to Yesh Balaram, General Manager, ARRB Systems Africa, about how his company's technologies are redefining automated road assessments.

What are some of your career highlights to date?

YB Being in charge of disruptive technology in the pavement engineering and asset management environment is both challenging and engaging. This brings about research opportunities that one would not find in a typical workspace and I am constantly learning new things.

I have authored various peer-reviewed papers and have had the opportunity to travel extensively to share my experience at conferences and seminars around the world. It’s always a pleasure to network and socialise with both new and old industry peers in a foreign land. This is all possible

Yeshveer Balaram, General Manager, ARRB Systems Africa

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IMIESA August 2020

The Roughometer 3 is a Class 3 IRI roughness measurement device suitable for both sealed and unsealed roads

because I am surrounded by exceptional people – from the young, talented and resilient team that I lead, to my accomplished mentors and visionary leaders.

What’s the current state of South Africa’s paved road network?

While our national roads are comparable to the best in the world, our provincial and municipal road networks are generally in an advanced stage of deterioration.

A vast number of roads are well beyond their original structural design life. There is an ever-increasing maintenance backlog, which threatens transportation logistics, increases road-user costs and reduces road traffic safety.

To further exacerbate these dynamics, the already constrained funding earmarked for road maintenance is being ineffectually utilised. This is largely due to a lack of credible and pertinent road condition information and inappropriate or non-existent road asset management implementation. The net result is that whole life-cycle management strategies are not applied. This obviously has a direct influence on our economic output.

Road traffic accidents for example, cost the economy around R160 billion each year!

How is ARRB helping to address the challenges?

At the centre of our pavement data collection operation is the

ASTM E-1656 compliant Network Survey Vehicle (NSV) fleet. The NSV has various subsystems that work in unison to collect comprehensive surface and functional road data. What sets our NSVs apart from other similar equipment is the fact that all subsystems are genuinely integrated and controlled through a single data acquisition and processing software system called Hawkeye.

This structure allows for a seamless spatial integration of all collected data streams including GPS, high-resolution imaging, 3D laser crack measurements (LCMS); geometry, such as slope, grade, horizontal/ vertical curvature; and surface profiles, such as texture, rutting and roughness.

The system operator (and others) can monitor all data streams in real time for quality control purposes.

Our intelligent Pavement Assessment Vehicle (iPAVe) and intelligent Safety Assessment Vehicle (iSAVe) have the same capabilities as the NSVs, but with the added ability to measure continuous pavement deflection and skid resistance, respectively.

How do these technologies influence asset management practices and maintenance budgets?

HOT SEAT To put it simply: better information leads to better decisions, leads to better maintenance practices, leads to better and safer road conditions! Up-to-date, accurate information is essential for transport departments to properly plan construction and maintenance activities and subsequently manage their networks in a cost-beneficial way. The utilisation of automated road assessments ensures objectivity, accuracy and an exceptionally high degree of repeatability in a fraction of the time when compared to conventional methods. This helps road authorities make better, more well-informed decisions.

Our technology is fine-tuned to identify problems as early as possible, saving time, money and lives. Road agencies recognise the considerable benefit that this technology brings to their road network management and are incorporating its use into their roads policies. This is Industry 4.0 in road asset management.

Where are the gaps in terms of current structural condition assessment practices?

One of the limitations with falling weight deflectometer (FWD) measurements is the frequency of data gathering. Five or ten points in a kilometre are insufficient to enable an accurate analysis of subsurface conditions.

The FWD is also slow and relatively dangerous in that each test takes around 30 to 40 seconds, with the vehicle being stationary and requiring formal traffic control.

Conversely, traffic speed deflectometer devices such as the iPAVe are capable of continuously measuring pavement response at traffic speed. This means more data points per kilometre can be safely measured. This results in a significantly more intensive insight of structural condition, thus identifying areas of weakness that could go undetected by an FWD or visual condition assessment.

How is the collected data managed and interpreted?

The golden rule of road asset management systems is to practice good data management.

ARRB’s specialist vehicles all automatically stream location, progress, data quality, and system health metrics to a cloud-based quality management program, accessible by the data collection manager. Good data management is especially true when working with big data. For example, the iPAVe measures profile/deflection bowl data at 25 mm intervals, records high-resolution images every 10 m, while the LCMS has a resolution of 1 mm x 1 mm, all of which translates to around 1 GB of data per lane kilometre.

The physical storage of large volumes of data can be risky and expensive. We employ a webbased solution called the Hawkeye Insight. The

processed data is published to a secure cloud-based server, where users can access the information from anywhere in the world over the internet.

Additional information, such as classified traffic counts and safety indices, can be added. In essence, data saves lives by combining machine intelligence with human intelligence.

Where are your technologies currently being used?

Our technologies are deployed all over the world. While we have a major presence in the USA, Australia, Asia and Europe, we also have global reach through our distributor network, which spans 23 countries. Closer to home, our technologies are used to support numerous provincial and municipal departments’ RAMS – the most recent being eThekwini metro. We also offer our services and equipment to other companies, such as consulting engineers, contractors and civil engineering laboratories.

Contractors realise the benefit of owning the equipment – such as the Walking Profiler – as it saves them time and, therefore, money, by using it as an integral part of their construction quality control. With the equipment on-site, there is no need to wait for external service provider availability and they can use it from project to project, enabling the initial investment to be paid off quickly and preventing unnecessary reworks.

Does ARRB provide solutions for gravel roads?

We most certainly do! Unlike paved roads, the condition and profile of gravel roads can change, quite literally, overnight. Experience shows that response type road roughness meters are best suited for measuring unpaved road conditions quickly and objectively.

We provide the Roughometer 3, which is a Class 3 IRI measuring device.

The Roughometer consists of a highprecision accelerometer that directly measures vehicle axle movement, thereby eliminating uncertainties such as suspension and passenger weight. It is integrated with GPS so the data can be formatted into custom graphs, tables and maps. This can be used in conjunction with an imaging

The Walking Profiler G3 is a high-precision measurement instrument for collecting surface condition information, at true walking speed

The Hawkeye 1000 digital laser profiler fitted to this vehicle measures longitudinal profiles, roughness and macrotexture

system to create a permanent record of the road and undertake post-rated condition assessments, which is the norm in many countries. The Roughometer is also used extensively in Southern and Central Africa, including Namibia, Mozambique and Kenya, confirming its robustness to withstand tough conditions.

What is your R&D team focusing on at present?

Our R&D team is constantly innovating, trying to find simpler and better ways to help our customers. We are continuously developing and updating our software to ensure we meet our customer expectations. We are also finalising an automated systematic TMH9 visual assessment capability. The Roughometer 4 prototype is currently undergoing initial testing and is expected to be released in 2021.

What is ARRB’s strategic focus for the balance of 2020 and going into 2021?

Our focus is on our employees and our customers. While we are living in uncertain times, we remain focused on our core purpose: to be the leaders in our field of expertise. The Covid-19 pandemic has forced us all to re-evaluate our strategic position and approach. To be successful in a highly volatile industry, staying steps ahead by rapidly adapting to changing circumstances is key to success and sustainability.

We will continue to invest in R&D, new technology and our people to maintain growth and business continuity. It is fundamental that we keep abreast of local and international trends as we strive towards our objective of being the global leader of pavement technological solutions.

www.arrbsystemssa.com

IMIESA August 2020

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The components of the blender unit packaged by D&H for shipping from Houston, Texas

Teamwork takes on new meaning when restrictions to personal movement necessitate people across cities and even continents working together remotely to achieve an engineered outcome.

Winning through remote teamwork

W

hen the multiple components for a new bitumen blending plant were despatched from Texas, USA, to Cape Town in midMarch 2020, no one could foresee the looming global severity of the Covid-19 crisis. Ordered by AECI SprayPave, this is the first plant of its kind in Africa. And with the lockdown in place, a complex assembly was going to prove even more challenging.

“Operating in a competitive market, AECI SprayPave needs to offer the whole spectrum of bitumen products,” explains company director Eddie Jansen van Vuuren.

“Bitumen rubber is one of the products we must produce to meet market needs and the new blending plant gives us this capability.”

Initially, the mobile plant will be used at the company’s operation in Parow Industrial,

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Cape Town, but can be moved anywhere in South Africa in containerised form. It comprises a 23 000 litre capacity aromatic/ extender oil tank, a 67 000 litre capacity bitumen base tank, a 23 000 litre diesel fuel tank, and a 550 kVA Cat generator – all supplied locally by Kenzam Equipment and built on to two trailers for ease of site establishment. Additionally, a blending unit and two 37 500 litre capacity reaction tanks were supplied by D&H Equipment, based in Blanco, Texas.

To give context to the complexity of the plant, the blending unit has the capacity to produce 25 tonnes/hour of rubber at 25% rubber crumb or 12 tonnes/hour of SBS polymer with a high shear mill. Each of the two reaction tank units has two compartments with separate, fully automated valving, heating, agitation and level indicators.

The D&H equipment left the Port of Houston on 13 March 2020. “Meanwhile, site preparations began in the AECI SprayPave yard in Cape Town while daily production continued on the other plants,” explains Stoffel Coetzee, a technical specialist based at the company’s branch in Alberton, Gauteng.

A giant puzzle The shipment arrived in Cape Town on 24 April during Level 5 of the lockdown. Landfilling, levelling and compaction had been put on hold from 27 March pending a further easing of restrictions.

Some restrictions were lifted on 1 May. This meant that limited AECI SprayPave personnel were allowed on-site, some production could recommence, and preparation work for the new rubber plant could continue. However, due to travel bans, D&H was unable to send any technicians from the USA to assist its new customer with the project.

The components of the D&H plant were cleared and delivered to AECI SprayPave on 11 May and Kenzam Equipment delivered the trailer units on the same day. Nobody was completely certain of what to expect of this new and unique plant. What arrived was like a giant puzzle consisting of various major individual components, as well as a 6 m long container filled with parts, consumables and spares. A series of steps had to be followed meticulously to get the plant up and running.

Lockdown restrictions prohibited all but essential local and interprovincial travel, so employees in Cape Town had to assemble

BITUMEN & ASPHALT TECHNOLOGY

Side view of one of the two reaction tanks The blender unit operating panel, with the heat exchanger visible to the rear

the units with the off-site help of Coetzee, assisted by Cape Town-based AECI Much Asphalt technicians Wesley Engelbrecht and Danie de Koker. Coetzee and Jansen van Vuuren subsequently travelled to Cape Town during June to compete a physical plant inspection and initiate the calibration and commissioning process.

Every step – from unpacking the parts to building pipelines, electrical work and assembling the units – was communicated thoroughly prior to execution. Randy Watt,

service manager, D&H, also remotely logged into the automated controls to monitor the system from 14 500 km away.

Calibrating and commissioning The first test batch produced through the automated inline system, running the plant at 16 tonnes/hour with 18% rubber content, provided accurate results to everyone’s satisfaction. Thereafter, the first recipes were loaded, and it was time to start the process for real.

With caution and online oversight by D&H in Texas, AECI SprayPave fired up the plant for its final test on 25 June. Two minor programming errors were experienced during the first run; however, once that was resolved, the first batch of bitumen rubber was successfully produced, marking a new milestone for asphalt innovation in South Africa.

“This project also showcases how technology and teamwork can achieve amazing results,” Jansen van Vuuren concludes.

Southern African Bitumen Association After 40 years Sabita continues to provide a valuable service to the roads industry, both local and international. Every success this Association enjoys is driven by member companies and other stakeholders equally dedicated in creating quality black top road in southern Africa.

• • • • • •

Continued development of bituminous material technology Production of world class technical guidelines and manuals Transfer of technology & knowledge with global partners Promotion of sustainable health & safety practices Provision of quality training that meets industry requirements Engagement of stakeholders on all issues relevant to a sustainable road network.

5 Lonsdale Building Tel: +27 21 531 2718 Fax: +27 21 531 2606

Lonsdale Way

Pinelands

7450

email: info@sabita.co.za website: www.sabita.co.za

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The right way to design and construct surface treatments

South Africa’s flexible pavement network is predominantly surfaced with specialist bituminous layers typically 20 mm or less in thickness. While thin in principle, technological advancements in bitumen formulations have made today’s asphalt surfaces highly durable. Getting it right depends on well-founded layerworks, optimal product selection and the right application techniques. By Gerrie van Zyl*

O

ngoing research, backed by case studies and forensic investigations into premature failure, has resulted in the development of high-performance bituminous binders over the pas t decade. Running in parallel have been updates to national specifications and test methods. In response, the Southern African Bitumen Association (Sabita) working groups have kept pace by updating Sabita’s manual on the design and construction of surface treatments.

Sabita Manual 40 (2020) will replace the national guideline document TRH3 (2007) for the selection, design and construction of surfacing seals, as well as existing Sabita manuals that include: • Manual 10: Bituminous Surfacings for Low Volume Roads and Temporary Deviations • Manual 28: Best Practice for the Design and Construction of Slurry Seals.

The updated document comprises eight parts, namely: • Part A: General • Part B: Materials • Part C: Performance • Part D: Seal type and binder selection • Part E: Design • Part F: Construction • Part G: Quality assurance

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• Part H: Repair of premature failures.

Part A provides background to the purpose and functions of surface treatments, the development of the local seal design method, and a summary of typical seals used in South Africa. Specific attention is given to basic requirements in terms of skid resistance, road surface macro texture and road tyre noise, the measurement thereof and typical values for different surface treatment types.

Development history highlighted that most of the design methods used for single and double seals in South Africa evolved from a concept of partially filling the voids in the covering aggregate to minimise the risk of whip-off.

Combining four different design methods Up until 1986, the four former provinces in South Africa adjusted their designs to suit their unique traffic situations, materials and climatic environments. This resulted in four different design methods, each giving a different recommended application rate for a given situation.

In addition to the four different provincial design methods, the first national guideline document (TRH3) published in 1986 added an additional complexity by suggesting a rational design method for seals in South Africa. However,

following push-back from industry, the Committee of Transport Officials (COTO) identified the need for its revision.

COTO initiated an investigation whereby only one standard method of seal design would be accepted. Adjustments in the basic assumptions of the rational design method resulted in the ability to obtain similar application rates that proved to be acceptable in different parts of South Africa over a period of 30 years.

Since publishing TRH3 (1998), a dramatic increase in the use of polymer modified binders for single and double seals has been experienced in South Africa, resulting in improved knowledge and performance data and further need for design adjustments. These and other improvements were incorporated in TRH3 (2007), which served the industry well for a period of 13 years.

Changes in the contracting environment, welldocumented performance studies, and improved knowledge on performance and risk minimisation resulted in the need to update TRH3 (2007). The urgency resulted in Sabita driving this initiative.

Materials and Performance Part B of Sabita Manual 40 (2020) addresses material requirements with reference to the latest SANS Specifications, TG1 document (The Use of Modified Bituminous Binders in Road Construction) and latest test methods.

BITUMEN & ASPHALT TECHNOLOGY

Significant adjustments to seal aggregate specifications for lower-volume roads are recommended to optimise the use of local sources. This is in line with the latest National Specifications for Road and Bridge Works (COTO 2020).

Part C discusses the influence of various factors on seal performance. Several examples are provided from forensic investigations and research, highlighting specific situations and binder/seal combinations that should be avoided.

Performance under different conditions provides valuable information for the selection of appropriate seals and binders. It also highlights the effects of poor construction and provides information for the adjustment and calibration of performance models for road asset management.

Upper pavement structure Of special interest is the influence of the upper pavement structure in terms of: A soft/low stiffness layer just below the seal, which could be the result of the base construction or ingress of moisture. Different investigations confirmed the value of reducing the moisture content in the upper base before sealing and confirmed that the radius of curvature (ROC) is a good indicator of crack initiation in any thin bituminous surfacing. Oxidative hardening of bituminous surfacings with time results in both increased stiffness and increased permeability, leading to a ‘glass plate’ on a ‘soft foam mattress’.

Coarseness of the base surface, resulting in base aggregate coming into direct contact with vehicle tyres. Referenced study results further confirmed that: • Polymer modified binders could increase the effective service life of a seal by 25%.

• Bitumen rubber binders increase service life by more than 70%.

• Rejuvenation sprays could increase the seal life by more than three years.

and highlights appropriate surfacings for the conditions selected: • 22 different surface treatment types plus an asphalt option • traffic volume • gradient (incorporating constructability and urban/rural drainage systems) • maintenance capability • traffic actions (turning and breaking) • equipment quality, experience and works method – e.g. labour enhanced • macro texture required for skid resistance.

Design Part E provides guidelines and processes for the design of various surface treatment types, as follows: • prime coats • uniform design sections • single and double seals • Cape seals (single seal plus slurry) • slurry seals • rapid-setting slurries and microsurfacings • inverted double seals • choked seals (racked-in seals) • geotextile seals • graded aggregate seals • stress-absorbing membrane interlayer (SAMI) • sealing through winter (embargo periods) • designing for very low and very high traffic volumes.

A step-by-step process for the design of single and double seals is provided with specific attention given to measuring and interpretation of input parameters.

Although the design diagrams as per TRH3 (2007) are incorporated, formulas are provided for calculation, and spreadsheet applications are available for download and use to determine appropriate application rates for single and double seals. This facilitates ease of sensitivity analyses.

Construction Seal type and binder selection Building on Part C, Part D discusses the factors to be considered for the selection of appropriate surfacings. It provides guidance for the selection of surfacings for: • initial construction • reseal type and binder, and type of pretreatment required • low-volume sealed roads • temporary deviations • forestry roads and game parks • small airports • footways and non-motorised traffic roads.

A spreadsheet tool is available for download and use. It considers the following variables

Part F deals with the construction of surface treatments and provides guidelines for each seal type. Numerous examples are given of poor and good practices.

With reference to Part C (Performance), a high percentage of premature failures relate to: • base quality before sealing • aggregate spread rate (too high) • uncontrolled opening to traffic.

Specific attention to these aspects is given to reduce the risk of failure. Of importance to note is that the construction process does not fully orientate and/or embed the seal aggregate.

This results in a sensitivity for the aggregate to dislodge when road surface temperatures

fall below the critical threshold for a specific binder. (Failing in either binder cohesion or binder/aggregate adhesion.) Controlled traffic compaction (at suitable temperatures) shortly after construction is essential to stabilise macro texture variation.

Quality assurance The focus of Part G is to ensure that the surface treatment is constructed with materials meeting the latest published COTO specifications, applied on a suitably prepared substrate and in accordance with best construction practice. New recommendations in terms of allowed macro texture are provided to ensure that the existing surface is suitable for the selected surface treatment type.

Emphasis is placed on simple on-site processes to minimise risk of failure – e.g. by enforcing trial sections to verify: • the ability of the contractor, the equipment, safety, traffic accommodation and the seal process management • the appropriateness of design application rates and aggregate spread rates • the sampling and testing location and frequency • the appropriate rolling type, methodology and sequence • the controlled process for opening to traffic.

Several diagrams are provided to assist with decisions regarding acceptance, conditional acceptance and rejection for each uniform design section (UDS).

Repair of premature failures Last, but not least, the purpose of Part H is to highlight the most common types of premature seal failures and to provide guidance regarding appropriate repair methods. Although premature cracking and delamination occur from time to time, most problems are related to aggregate loss and bleeding.

“The document has been reviewed and final comments are currently being evaluated and incorporated,” explains Saied Solomons, CEO, Sabita. “Once this process has been completed, Manual 40 will be made available on our official website, together with spreadsheet applications for selection and design.”

Highlights from this manual and changes from TRH3 (2007) will be shared through the Society for Asphalt Technology seminars, plus the existing South African Road Federation ‘Seal Design and Construction’ course. The latter has been amended to incorporate current best practice. *Gerrie van Zyl, Pr Eng, is a director at Mycube Asset Management Systems.

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ROADS & BRIDGES

The power of geosynthetics For nearly 140 years, Maccaferri has been developing innovative, sustainable engineering solutions. Our teams are on hand to offer full technical support, including analysis and design, product selection and installation supervision. By Samantha Naidoo*

G

FIGURE 1 Geosynthetic uses

eosynthetics can be designed from below subgrade level as geocomposite drainage to glass fibre geogrids with the overlay of the road layerworks – as highlighted in Figure 1. To assist in the design process, Maccaferri has developed a sophisticated software package, MacREAD. The software enables the design and optimisation of the full road structure, including both unbound and bound layers, in standard and improved conditions through the addition of geosynthetics within the various layers.

ASPHALT REINFORCEMENT When flexible asphalt pavements are exposed to repeated cyclical loads, rutting, pothole formation and fatigue cracking can occur. With increasing vehicle use and axle loads, this problem may get worse. The reinforcement of asphalt pavements can produce a threefold increase in the service life of highway pavements by reducing fatigue, reflective, thermal and settlement cracking.

Maccaferri offers a range of reinforcement products for bituminous paving. Whereas MacGrid® AR glass fibre and polyester geogrids inhibit reflective cracking, RoadMesh® additionally structurally reinforces the pavement. RoadMesh provides lateral restraint to the asphalt, which improves resistance to rutting and shoving.

Rehabilitation of P88 Durban, South Africa Product: RoadMesh & MacGrid AR 10A.7 Problem Cracking, deformation, rutting and potholes were just some of the problems encountered

on the P88 leading from the Sappi Saiccor factory to the P541, which connects to the N2 in Umkomaas on Durban’s South Coast.

Site investigation revealed the road to be very old, constructed using the waterbound macadam method over the compressible alluvial soils associated with the river next to the road. The main failure was in the base layer, caused by a combination of excessively heavy loading (predominantly logging trucks and the occasional sugar truck) as well as a variable road pavement construction.

The length of the road was divided into two zones that needed rehabilitation. The first was considered as complete failure – low areas, uphill areas and where ponding occurs. The second was considered as semi-complete failure, which included the less critical areas.

Solution A comprehensive analysis of the pavement structure was performed, considering the road to be a Category Class C as per TRH4.

An 80 mm HMA overlay was considered over the existing surface, lasting only 0.7 MESAL according to South African Mechanistic

FIGURE 2 Potholes and cracking on the existing pavement

FIGURE 3 During construction: Installation of RoadMesh

Case History 1 – Asphalt Reinforcement

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Design Method – compared to the 1.7 MESAL required. A RoadMesh was then considered and designed with Maccaferri’s internal software, OlCrack, producing a TBR (traffic benefit ratio) of 2.5, exceeding the design traffic load.

On the segment that was deemed to have completely failed, 8 000 m² of RoadMesh was used on the 840 m section. The mesh was manufactured to a width of 3.1 m to accommodate lane width. On the segment that was deemed to have semi-completely failed, 5 200 m² of MacGrid AR 10A.7 was used.

After comprehensive analyses, the solution was derived by the parameters that included effectiveness, cost and time.

SUBGRADE IMPROVEMENT & GROUND STABILISATION Pavements that are bound or unbound are exposed to repeated, highly focused loads, which can cause precipitate ageing and failure of road construction. Thus, roads should be constructed in strong soil deposits and the behaviour of the road surface depends on

FIGURE 4 Installation of MacGrid AR 10A.7 with deployment frame

ROADS & BRIDGES

the strength of the fill material and subgrade below it (Maxwell, 2005).

Good quality subgrade and fill materials are not always available in road design and construction. Improvements to subgrade can be achieved by using geogrids or a combination of geosynthetics. Appropriately designed and installed reinforcement placed within unbound granular layers improves the performance of the road, extending its life and increasing maintenance intervals.

Woven geogrids and extruded polymer grids provide a complete solution to reinforcement and stabilisation of the unbound layers, and can be used in conjunction with woven geotextiles and geocomposites to form a separation barrier to prevent interlayer contamination. Woven polypropylene and hightenacity polyester geotextiles geocomposites are used to provide cost-effective separation and reinforcement of unbound roads on soft ground.

Case History 2 – Glentana Subgrade Improvement Product: MacGrid EG 30S Problem The investigation of the road revealed that major a deep-seated deformation had taken place over certain sections of the road. A geotechnical investigation indicated the presence of a deep (up to 8 m in certain locations), soft, low-strength subgrade.

Various pavement rehabilitation options were investigated during the design stage of the project. This included, among others, the removal and replacing of the poor subgrade material. This option was found to be impractical considering the depth of the poor subgrade and the restrictive environment of the road.

Other options investigated included the use of micro piling but, due to the high cost, this option was also not considered to be viable.

The rehabilitation strategy that was found to be the most cost-effective was a ground stabilisation technique using geosynthetics in order to reduce the overburden pressure caused by the increase in pavement thickness.

FIGURE 5 During construction: placing of asphalt layer

PROMOTING WOMEN IN ENGINEERING Samantha Naidoo plays an active part in training and skills development in the industry.

As a female professional engineer, her drive and passion are in the investment in the recognition of young female engineers.

What advice do you have for young professionals looking forward to joining the profession?

SN My advice is: • Work hard to prepare for the academic requirements needed for engineering. What you put in is what you get out.

• Explore faculties that give you realistic job opportunities.

• Mentorships – it will always be beneficial to gain knowledge and guidance from an engineer.

• Question everything – this can help you decide on your field of study.

• Keep learning – keep abreast of current technologies and engineering news. A wellinformed person is more employable.

What is your management and leadership philosophy?

Leadership should allow individuals to apply their mind and become innovative thinkers.

Allow young engineers to make choices and encounter obstacles that will allow them to grow and learn. Mistakes often make for the best and most memorable lessons, and failure should never impede your progress.

Recognise your duties and obligations as a young engineer and develop skills that help you progress. Teamwork and respect for other’s ideas are very important. For me, a good leader is able learn, adapt and set standards for the next generation of engineers.

As Thomas Edison said, “Our greatest weakness lies in giving up. The most certain way to succeed is always to try just one more time.”

How well represented are women in STEM? In 2016, women made up only 23% of STEM talent globally. According to the Engineering Council of South Africa, only 11% of registered engineers are female and only 4% of those are professional engineers.

We as professional engineers and technologists need to encourage, mentor and grow the industry. Increasing STEM education participation and proficiency for girls starting in school is a critical step. Mentorship is often cited as a key strategy for exciting, supporting and keeping students, young scientists and engineers in the STEM fields.

Remember the historical day of 9 August 1956. Remember what was fought for. Remember that we are strong and can only get stronger. Happy Women’s Month.

Solution One of the main design criteria was to maintain an undisturbed stress state in the soft, poor subgrade material to avoid deformation and resultant failure. A traditional design – run using the South African Mechanistic Pavement Design Method - SAMPDM considering a road Category B as per TRH 4 with an ES3

(3 million ESAL) – resulted in a total pavement depth of 1.2 m.

The results from the model shown in Figure 8 were placed, one in the G7 and one in the G4 base, reducing the excavation from 1.2 m to 0.7 m. This achieved a no-stress variance in the soft layer (which would have failed due to the overburden pressure caused by the extra layer thickness), as well as maintained the same road surface level, which was paramount due to the main intersections and road annexures.

Construction commenced in March 2014.

Stormwater reticulation along the edges of the road prism was upgraded before proceeding with the layerworks. Due to traffic

FIGURE 6 Construction completed

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ROADS & BRIDGES

FIGURE 7 SAMPDM pavement structure

time. The request was accepted by the client and traffic was redirected through the surrounding municipal areas.

By constructing in full width, the contractor was able to lay down the geogrid in one operation, minimising jointing and effectively only using three roll widths to cover the road prism. The first geogrid layer was placed on the road box cut and then covered with a G7 subgrade. Particular attention was given to jointing of the geogrid. A minimum overlap of 300 mm was required to ensure the tensile forces in the geogrids would be transmitted through the layerworks.

CONCLUSION

FIGURE 8 AASHTO design improved with geogrids

constraints, the contractor was only allowed to work half-widths.

The contractor requested access to the full width of the road to reduce the construction

Technology has advanced extensively with utilising geosynthetics in roads. To carry out effective implementation of a project, one must consider field testing as well as design calculations backed by years of research in the field of geosynthetics. Time and costeffectiveness assess heavily on project outputs and, with the use of geosynthetics, this becomes increasingly easier. *Samantha Naidoo is the manager: Special Projects at Maccaferri Africa. She

FIGURE 9 First layer of geogrid placed under G7 material

is a professionally registered engineering technologist with over 15 years of experience in the geosynthetics industry. Her key focus areas are to develop and implement appropriate measures and procedures for the effective implementation of projects, which includes the management of the design, construction and contracts of projects.

www.maccaferri.com/za

eZimbokodweni bridge’s ‘glow in the dark’ parapets are fabricated from photoluminescent concrete polymers

Bridges that glow in the dark The pioneering adoption of photoluminescent concrete polymers adds a new dimension to infrastructure projects. Alastair Currie speaks to Josh Padayachee, director: Bridges and Buildings at Naidu Consulting, about how a passion for innovation is helping improve community safety. A recent example is the eZimbokodweni pedestrian and pipe bridge project.

T

he concept of using glow-in-thedark concrete polymers for local infrastructure projects stemmed from a simple brainstorming session. The quest was to find an alternative to costly electrical lighting systems.

To further develop the idea, Naidu Consulting approached South African specialist Resocrete Composites to investigate the possibility of developing a range of product applications for the illumination of pathways, bridges and highway structures. This led to the formation of a research and development initiative between Naidu Consulting, the University of KwaZuluNatal and Resocrete Composites, which is currently ongoing.

Using pigments to change the colour of conventional concrete has been a standard

practice for decades. Until recently, though, it wasn’t possible to create photoluminescent effects. This is chiefly due to concrete’s opaque nature, as well as the way it hydraulically bonds during the cementitious process. The absorption and emission of light is only possible in materials that allow light to pass through them, so that rules out standard concrete.

This is an international, first-of-a-kind breakthrough using synthetic resins as a basis to create polymer concretes that can now be chemically infused with phosphorescent particles. The ratio of polymer and photoluminescent particles, as well as the thickness of the photoluminescent layer, determines the level of potential energy storage.

As this photoluminescent polymer concrete is introduced worldwide, it will continue to grow in popularity, thanks to the following key features: • It is a green product that can make extensive use of recyclable materials.

180 160

Luminosity (mcd/m²)

140 120 100 80 60 40 20 0

30

60

120 Time (min)

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240

360

720

The initial light intensity drops off in the first two hours, and thereafter provides a sustainable glow for around 10 hours

• Steel reinforcing is not required.

• It is lighter and stronger than conventional precast concrete.

• It is an alternative energy/lighting source using renewable energy.

• It is a long-term, virtually maintenance-free and cost-effective product.

How it works Phosphorescent particles absorb light during the day and release them as stored energy once the sun begins to set, forming a luminous glow. Based on available studies, the light intensity is at its brightest initially and then starts to decrease at a faster rate in the first two hours. Thereafter, it stabilises and gradually decreases for the next 10 hours – in the process, providing improved sight distances for both drivers and pedestrians at zero energy cost.

“The key emphasis of photoluminescence is to aid in the identification of critical areas during the night, so it’s not a substitute for traditional lighting, but rather a valueadded contribution to pedestrian and road safety,” Padayachee explains. “However, as a lower-cost intervention, and with an expected lifespan of at least 20 years, there’s huge scope for the wider adoption of this technology.”

Possible applications include: • making parapets on bridges visible

ROADS & BRIDGES

The footpaths leading up to the bridge feature photoluminescent strips prefabricated into the precast panels

The new structure serves a dual function as a pipe and pedestrian bridge. The piers support precast concrete beams that were delivered to site and lifted into position by mobile cranes

and other reasons, which include maintenance and replacement, lighting has been eliminated on many bridges and roads,” he adds.

eZimbokodweni’s new sewer connection, which ties into the main line.

The reinforced concreted bridge deck was later positioned on top to complete the design

• lighting up walkways on pedestrian structures • providing a guiding light on stairwells and corridors • i lluminating the approaches to bridges • p roviding an alternative to road markings • improving the visibility of signage • enhancing aesthetics in and around buildings and public recreational facilities.

“Photoluminescence has a place when the electrical lighting of roads and bridges is not feasible. This may be due to the remoteness of the site, recurring cable theft or a lack of electrical infrastructure,” Padayachee explains.

“Where electricity is available, the high cost of lighting – especially if conventional metal halide lamps are used – also makes this an uneconomic option for many municipalities.

Switching to LED lamps brings down the costs but increases the risk of vandalism. For these

Illuminating the eZimbokodweni bridge A recent project appointment by eThekwini Municipality, Water and Sanitation Unit provided the perfect opportunity for Naidu Consulting to showcase the application of photoluminescent concrete polymers. The scope of works entailed the design and construction management of the eZimbokodweni sewer pipe and pedestrian river bridge in uMlazi, south of Durban. The main contractor was AfroStructures.

In the past, crossing this section of the uMlazi River was only possible via a low-level concrete footbridge, which became impassable during flood conditions. There was also an existing sewer syphon traversing the river and underlying the footbridge. This needed to be upgraded due to regular blockages.

Both structures were also being progressively undermined due to illegal sand quarrying.

That paved the way for their demolition and replacement.

The eZimbokodweni bridge was formed using custom-made precast concrete beams supported on cast in situ piers. As per the design, the new elevated and gravity-fed sewer pipeline is housed in the lower section and

closed off with a concrete deck to form the pedestrian walkway.

The most distinctive element though is the bridge’s specially designed photoluminescent parapets, which were manufactured and supplied by Resocrete Composites. To add a further dimension, the precast concrete polymer footpaths approaching the bridge also feature luminous strips.

“The fact that the new bridge delivers improved sanitation services, plus a secure pedestrian crossing in all weathers, was a major cause for celebration,” says Padayachee. “However, the bridge’s glow-in-the-dark parapets and footpaths were welcomed with even greater joy and enthusiasm by the eZimbokodweni community. This bridge redefines how form and function can come together.”

The eZimbokodweni project demonstrates that creativity doesn’t always have to come at a prohibitive cost or compromise on safety when delivering infrastructure. It also showcases how technology can improve the quality of life and allow communities to reimagine their future.

“Working with eThekwini and our project partners, we’ve opened up a whole new world of possibilities for increased pedestrian and roadway safety in rural and urban areas, and it’s not reliant on electricity,” Padayachee concludes.

A daytime perspective of the bridge

ROADS & BRIDGES

Franki supports the Great River Bridge in Mauritius

Artist’s impression of the Great River North West Bridge

Paving the future for one of the most aesthetic infrastructure landmarks in Mauritius, the Frankipile team achieved another milestone with the successful completion of the foundations for a new iconic ravine bridge.

By Roger Feldmann*

L

ocated south of Port Louis, the A1 M1 bridge – as it is commonly referred to – will effectively connect the areas of Chebel and Sorèze on either side of the Great River North West Valley and finally join the main A1 and M1 arterial roads.

The Road Development Authority (RDA) of Mauritius has been planning a bridge to link these two areas on the eastern and western side of the valley for

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some time in order to ease the growing vehicular traffic congestion in the area and provide a dedicated pedestrian walkway between Chebel and Sorèze. Finally, on 11 April 2018, the government of Mauritius and the RDA launched the construction of the A1 M1 link as part of the larger road decongestion programme.

Frankipile Mauritius International, a Keller Company, was appointed by the client to supply and install the specialised piled foundations to support the two piers of the bridge.

“The new bridge is based on a classic extradosed design and is the brainchild of Systra International Bridge Technologies,” says Mirvesh Jugurnauth, contract engineer and manager, Frankipile Mauritius. “Boasting a bridge deck length of 330 m and supported by two piers towering in excess of 80 m from the river level, the bridge is set to become a national landmark.”

The bridge deck incorporates a dual-lane asphalt surface for vehicles, a pedestrian walkway on each side and two observation decks, guaranteeing spectacular sunset views over the Indian Ocean.

Between a rock and a hard place The comprehensive geotechnical report provided by ARQ Consulting Engineers and the position of the two piers posed distinct logistical and technical challenges to the foundation solution.

First, it was clear that the piles needed to be founded in the hard rock basalt some 18 m to 22 m below the riverbed level.

Second, it was evident that the final pier positions were located in the largely inaccessible 100 m deep ravine, making it extremely complex for the heavy-duty piling equipment and materials to reach the site.

The underlying soil profile at each pier position revealed a combination of silty gravels, colluvium, clay, rock layers and boulders common in riverbeds. The pile design called for a total of 40 piles per pier, and each pile was 1 080 mm in diameter.

The piles were designed to carry a working load of 8.85 MN. Through careful coordination and planning with the main contractor (made up of the Transinvest-General Construction Co-Bouygues TP-VSL Joint Venture), the experienced Franki team was able to mobilise

ROADS & BRIDGES the large track-mounted piling equipment to the engineered platforms at the pier positions in a safe and carefully controlled manner. Franki used a combination of a powerful Bauer BG20 piling rig to handle the drilling and a Liebherr 845 crane to service the site, weighing in excess of 70 t and 50 t, respectively. This robust combination was well suited to handle the installation of the 1 080 mm Ø piles to a depth of 20 m.

The Franki team was fully prepared for the anticipated ground conditions.

Belts and braces “To overcome the complex soil profile, a combination of rock augers, coring buckets and a chisel were used. Where thick rock layers were encountered, a cluster drill was used to penetrate them,” explains Jugurnauth. “The cluster drill incorporates numerous small down-the-hole (DTH) hammers and is specifically designed to penetrate hard rock. Having both methods available on-site enabled the team to reach the required founding depth with relative ease, regardless of the ground conditions.”

This ‘belts and braces’ approach ensured Franki was able to meet the approved programme and complete the project on time and within budget.

Due to the upper soil profile and the high water table, temporary steel casings were used to ensure the integrity of the pile shaft. The piles had to be cast underwater using a gravity-fed tremie pipe system. The high-slump, self-compacting concrete mix was transported to the pile positions using traditional readymix trucks.

Preparing the pile cap encompassing forty piles of 1 080 mm diameter each

In order to meet the tight timeline of the contract, the Franki team worked a double shift each day.

“All things considered, and with the strong commitment from the team, the project was plain sailing,” adds Yannis Mongelard, country manager, Frankipile.

They proved to be cost-effective for tests with very high test loads. These tests were carried out by Fugro Loadtest to a maximum load of 17.65 MN. The test piles performed extremely well, with settlement of 7 mm at 14.5 MN and 11 mm at 21 MN.

Safety first Osterberg cell (O-cell) testing In a first for Mauritius, two O-cell tests were carried out to verify the design and construction of the foundation piles. O-cell tests require no kentledge or reaction piles.

The robust combination of the Franki Liebherr 845 (left) and the powerful Bauer BG20 (right) piling in the Great River North West Valley in Mauritius, where an iconic ravine bridge is being built

The platform at Pier 2 was very close to a steep cliff, which posed a safety risk due to potential rock fall. A sturdy catch fence was designed by ARQ and installed by the main contractor above the pier position to protect the works below.

In line with Franki’s stringent safety standards, the ‘Think Safe, Work Safe, Go Home Safe’ mantra was always top of mind.

The piling contract was completed with no lost time incidents recorded.

“This prestigious project emphasises Franki’s diverse technical exper tise and capability to successfully overcome the unique piling challenges related to infrastructure of this nature,” concludes Dr Nicol Chang, group technical director, Franki. *Roger Feldmann specialises in business development at Franki Africa.

www.franki.co.za

IMIESA August 2020

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STORMWATER & URBAN DRAINAGE Sustainable urban drainage systems (SUDS) are slowly gaining traction in South Africa, but more awareness and training are needed to successfully increase their wider adoption, says Justin Kretzmar, sales engineer, ISG Group, which incorporates the Rocla and Technicrete manufacturing divisions.

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roundwater replenishment and water reuse are now top of the list of sustainable interventions for municipalities, particularly those in drought-affected regions, backed by stricter regulations on how stormwater is attenuated and managed.

“As green spaces lose ground to urban development, the resulting increase in hard surface areas intensifies stormwater run-off volumes, which greatly exacerbates downstream river erosion,” Kretzmar explains.

“To counter the loss of natural drainage into the water table, among the best solutions are SUDS and more specifically permeable paving, which collects, attenuates, and actually purifies stormwater before infiltrating it back into the environment.

“Alternatively, stormwater can be intentionally stored and reused for greywater. As a further plus, these systems have been proven to filter out heavy metals from the water, as well as small concentrations of hydrocarbons,” he continues.

Permeable paving Different to what you think ABOVE Aqua Zig-Zag permeable pavers (left) integrated with Technicrete’s standard Double Zig-Zag units (right). The gaps shown in the Aqua Zig-Zag pavers will be filled in with small stones that form part of the integrated filtration system RIGHT Stone infill completes the permeable paving installation

Within its Aquaflow permeable paving range, Technicrete fields the Aqua Trojan Slab and Square®, plus the Aqua Zig-Zag®.

When installed correctly as a complete system, these pavers allow rain to flow through the paved surface layer into purpose-designed stone layerworks. Thereafter, the water is released in a controlled manner into stormwater systems or watercourses via installed drainage pipes.

Alternatively, the system can be designed to intentionally allow steady infiltration and thereby recharge the underlying water table via porous geomembranes, which prevent any fines loss that might undermine the system.

The system could also be lined with an LDPE/ HDPE membrane to store water for reuse.

Subtle by design Installing permeable paving on the prepared sub-base layerworks

Aquaflow products are almost identical in design to Technicrete’s standard pavers. The key distinction is that they have drainage

gaps or recesses. The intention is to get the stormwater to drain through the paved layer, after which the rest of the system kicks in.

“Underneath the paving and bedding are stone layerworks that have up to 40% air cavities. Collectively, these form a holding ‘tank’,” Kretzmar continues. “A square metre of stone layerworks 300 mm thick with 40% cavities can store up to 120 litres of water, so there’s potential to temporarily capture, hold and release a substantial amount of stormwater, depending on the scale of the permeable paver installation.”

For example, a municipality might specify that a development needs to have a maximum stormwater discharge rate of 50 litres per

A completed permeable paving installation at an industrial site

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second. The SUDS designer will then factor this into the storage calculation based on the square meterage of the ensuing paved area and storm data. For infiltration-designed systems, it is essential to conduct in situ permeability testing on the in situ soil.

Getting the installation right However, even the best SUDS designs will quickly unravel if poor installation practices are applied, which remains a recurring issue in South Africa. Numerous contributing factors could include incorrect layerworks depth, incorrect materials and/or poor construction; not making provision for local weather and surrounding vegetation, like excessive falling leaves; and poor maintenance practices. Maintenance interval recommendations must be built into the engineering report up front, since they are critical and very site specific.

“Permeable pavers are always bedded on small stone layers, and never on river sand, as per conventional paving. We’ve also seen situations where permeable pavers have been placed directly on compacted earth, or a layer of compacted riversand or G5, which is a problem as this type of layerworks cannot accommodate the inflow of water and will most certainly fail,” Kretzmar continues.

Routine maintenance also needs to be factored in, with the intervals determined by the extent of possible contamination from windborne debris, typically ranging from every 2 years up to every 10 years.

(Preventing contamination during installation is equally important.) Left unchecked, the best system will eventually clog up. This typically occurs in the top 25 mm to 35 mm of the paving layer infill.

In regions like Europe and the USA, SUDS are well entrenched, with regular servicing of these installations using specialised trucks that loosen, suck up and replace the small stone columns filling the paver recesses. These specialised trucks are not yet in South Africa; however, there’s a good opportunity for local OEMs to develop smaller equipment that performs the same job.

Locally, Technicrete recently secured a contract to supply approximately 8 000 m2 of permeable paving for one of the metros as an inner-city stormwater management intervention. Included in the contract is a further 8 000 m2 of standard paving.

“There’s a lot of work being done on permeable paving in South Africa, but the traction should be far greater, especially when you consider the benefits compared to conventional stormwater designs.

On top of that, SUDS add a proven environmental benefit that cannot be ignored,” Kretzmar concludes.

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Schools built with bricks Investing in education infrastructure is vital for South Africa’s future. In turn, every school should be the embodiment of stability, permanence and strength.

And their building materials should reflect this, says Mariana Lamont, executive director, Clay Brick Association of Southern Africa (CBA).

By Alastair Currie

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any of South Africa’s schools that date back to the early 1900s were formed using clay bricks as the main design element. The fact that they continue to stand today, more than 100 years later, in near pristine condition is thanks to the natural durability and relatively maintenance-free nature of this fired clay material. This is especially the case for exposed brick and face brick buildings.

Clay bricks are entirely natural, contain no pollutants or allergens and are resistant to ants, borers and termites. They are also inert and don’t release volatile organic compounds or toxic fumes that would otherwise impact on air quality and compromise health and safety.

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“Money spent on maintaining existing buildings could be better used for enhancing learning experiences through new facilities and teachers, which has a direct bearing on how current and future schools are designed and constructed. In this respect, the natural structural strength and dimensional stability of clay brick, coupled with its high fire rating, make it a practical and safe choice,” says Lamont.

Thermal efficiency and weather Other key distinctions about clay brick are their proven energy-efficient properties and ability to withstand extreme weather conditions. In addition to being water-resistant, the outer layer naturally absorbs moisture.

“Walls that become damp dry out just as quickly (without ugly colour changes).

Clay bricks also have well-known thermal insulating properties, offering natural coolness in summer and warmth in winter,” Lamont explains.

Together with their ability to regulate air humidity, learners and teachers can enjoy an environment close to the preferred human comfort zone in both the coolest and hottest months. This natural temperature regulation significantly reduces the need for mechanical heating and cooling (where available) and lowers energy costs.

Sound attenuation is another important feature. The density of clay brick resists the transmission of airborne sound waves. This shields learners and teachers from excessive noise via adjoining buildings or classrooms.

Clay brick versus ABTs Increasingly, clay brick competes with alternative building technologies (ABTs) like steel frame construction, timber, tiltup construction, prefabricated kits and 3D printing. ABTs are especially popular where the user requirement is for a modular, quickly erected and easily replicated solution.

Purpose-designed and using first-class materials, ABT systems can perform well for decades. However, where the original

BUILDING SYSTEMS

design intent is for a quick, cheap and more temporary solution, then comfort and durability are not the primary deciding factors. Another point to consider is that not all ABT systems are locally produced or quality approved. In contrast, clay bricks produced by CBA members meet SABS, NHBRC and other local and international standards. Clay bricks are also mined and manufactured in South Africa.

Locally, ABTs form part of the mix for the execution of programmes like the Accelerated Schools Infrastructure Delivery

Initiative (Asidi). Asidi targets more than 3 000 schools across South Africa for reconstruction or service improvements. The issue here is whether short-term gains, like prefabricated accommodation, achieve a beneficial result.

The CBA argues that temporary solutions frequently end up costing more in the end, and not just in terms of infrastructure and maintenance costs. There’s also the overriding human factor to consider. Unlike clay brick walls, for example, the insulated lightweight walls typically used to construct prefabricated container-type buildings are

unable to self-regulate temperature. Unlike the thermal mass of clay brick walls, the heat remains trapped inside. In the absence of air conditioning, the result is a hot box that creates an uncomfortable and inefficient learning environment for most of the school day.

“The evidence clearly shows that clay brick stands the test of time for generations. Even more significantly, though, the aesthetic appeal of brick adds a sense of security and stability, a feeling of pride and belonging, especially when these schools are built for and by their communities,” Lamont concludes.

BUILDING SYSTEMS Once seen purely as a civil engineering intervention, the striking geometric shapes and stone composition of gabion structures are now gaining ground in the architectural segment. At times, there’s an opportunity to combine both disciplines, says Louis Cheyne, managing director, Gabion Baskets. By Alastair Currie

Gabion architecture

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ithin the smart cities of the future, the need to remain connected to the natural environment is a key theme. This strongly influences the evolution of industrial art and architecture as designers and town planners rethink how buildings and infrastructure impact positively or negatively on urban dwellers.

“Every structure has a function, but that doesn’t mean the resulting form can’t have strong aesthetic appeal,” says Cheyne.

For civil engineering applications, hexagonal double-twisted steel wire mesh remains the

2 m free-standing wall typical section

mainstream choice due to its strength and inherent flexibility. The latter is especially important for river erosion and weir structures, where sustained water velocities, seasonal flooding and some degree of flotsam impact must be built into the design.

Over the years, the natural beauty of gabions has increasingly caught the attention of architects, landscape architects and infrastructural planners as a viable alternative to precast concrete block retaining systems. Typical gabion projects include bridge abutments, commercial and industrial mass gravity retaining walls, and stormwater works, including attenuation dams.

50 x 50 x 3 mm welded mesh 2 x 1 x 0.5 mm baskets

75 x 75 x 5 mm square hollow section cast into concrete at 2 m centres

Ground level

0.5 x 0.5 x 0.2 m foundation standard

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25 MPa concrete for free fencing

A welded mesh retaining wall constructed within Sandton’s central business district

“An interesting development has been the use of wire-mesh gabions for non-structural applications, like fence posts, public seating and free-standing walls,” Cheyne continues.

“However, that trend is now being rapidly overtaken by major interest in welded mesh – a system that can perform both architectural and engineering roles. The exception would be river and marine protection works since the product is too rigid. In these environments, gabions need to be able to flex or the wires will eventually break under the strain. In contrast, the rigid and flat front face design of welded mesh makes it ideal for specific effects, like perfectly formed lines or the cladding of buildings.”

Aperture configurations All welded mesh products supplied by Gabion Baskets are Class A galvanised, with the option of three standard aperture configurations, namely 50 mm x 50 mm, 50 mm x 100 mm, and 75 mm x 75 mm. The most popular option is the 50 mm x 50 mm, which is also the strongest in terms of rigidity. For all systems, the standard wire diameter is 3 mm, unless otherwise specified. Mesh panel dimensions are cut to size for each specific project.

Class A wire is manufactured with a zinc coating to counter corrosion and is recommended for most applications, particularly in coastal zones.

However, some designers specially request ungalvanised wire with the intention of creating a weathered patina effect.

BUILDING SYSTEMS A close-up view of a welded mesh section

Gabion mesh panelling used to form fence posts

To study the extent of longer-term inland corrosion on ungalvanised wire, Gabion Baskets erected an outdoor freestanding test structure at its Sandton factory. A slightly thicker 4 mm welded mesh wire was used to factor in future corrosion, chiefly from rain and windborne dirt. After some three years of exposure, the corrosion remained superficial.

As a starting point, welded mesh panels used as building cladding need to be correctly anchored.

Depending on the wall height and weight of the infill material, the recommended approach is to use a combination of angle irons and steel plates spaced at 0.5 m to 1 m intervals. These are positioned vertically and/or horizontally to secure the rear mesh panel to the wall. The facing mesh is then laced securely to form the final rectangular shape.

“To fill welded mesh panels, installers on-site simply need to pour in the materials,” says Cheyne. “That’s a major departure from your conventional hexagonal double-twisted woven mesh baskets, which need to be meticulously packed by hand to achieve the optimal shape and stability. For this reason, welded mesh panels are so much faster and simpler to install.”

Mesh gabions are typically formed using in situ rock, river pebbles or commercially sourced quarried material. The use of sandstone, combined with PVC wire coatings in specific colours, can provide an especially attractive rustic finish; however, since welded mesh panels are smaller and flatter, any type of material can be used, ranging from white and pink quartz, to shells and recycled products. Since it’s only the front face that will be displayed, designers can save on costs by filing the core with cheaper materials, provided they don’t degrade over time. Welded mesh with PVC is also available and is a good option for coastal belts.

Welded mesh structures As with the traditional hexagonal twisted-wire systems used predominantly in civil applications, welded mesh projects have specific installation requirements. This has a bearing on the size and quantities of rock required, fill techniques, the foundations, and structural support.

Typical section 100 x 100 x 6 mm welded mesh gabions

Free-standing mesh Alongside cladding systems, free-standing mesh walls are growing in popularity for commercial, industrial and residential projects. The same is true for perimeter walling, fence posts, public seating and pillars used for signage.

75 x 75 x 5 mm angle bolted to wall with M10 bolts @1 200 mm centres

A free-standing gabion mesh wall, using sandtone fill to create a natural effect

Free-standing walls generally range in height from 2 m to 3 m, but can be higher, and tend to be under 500 mm in width. Given their weight, the design recommendation is that the reinforced concrete foundation should have a minimum width of 500 mm. Structural steel columns anchored into the concrete form the central support throughout, with the fill material packed around it. Making sure the wall is secure is important in case of potential wind loads or vehicular impacts.

Where designers prefer to use wire mesh gabions for free-standing structures, formwork is required to support the baskets during installation and filling. This makes the process far more complex compared to welded mesh.

“It’s fascinating to see how seasoned gabion designers and contractors that used to focus predominantly on functionality are now placing equal weighting on aesthetics,” adds Cheyne.

“Whether our habitats are rural or urban, gabion structures maintain our connection with the natural world that sustains us. They also provide durable and inspiring structures that stand the test of time for generations,” Cheyne concludes.

Front elevation

Existing wall 50 x 5 mm plate 200 mm long bolted to wall with 2 x M10 bolts

75 x 75 x 5 mm angle bolted to wall with M10 bolts @ 1 200 mm centres

A cross section showing the typical anchoring method for an external wall cladding system

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CEMENT & CONCRETE

The role of glass and steel fibres in concrete The toughness and tension of concrete made with Portland cement can be greatly improved by the inclusion of certain fibres in the mix. Bryan Perrie, MD of The Concrete Institute, discusses the role of glass and steel fibres.

Bryan Perrie,

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oday alkali-resistant glass fibre is used in the manufacture of glass-reinforced cement (GRC) products that have a wide application range. Initially, though, glass fibres were found to be alkali-reactive and products in which they were used deteriorated rapidly. As research and development progressed, however, alkaliresistant glass containing 16% zirconia was

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managing director, TCI

successfully formulated in the 1960s and was in commercial production in the UK by 1971. Running in parallel, other sources of alkali-resistant glass were also developed during the 1970s and 1980s with higher zirconia contents.

In terms of composition, glass fibre is available in continuous or chopped lengths. Fibre lengths of up to 35 mm are used in direct spray applications and

25 mm lengths for premix processes. They exhibit high tensile strength (2-4 GPa) and elastic modulus (70-80 GPa) but have brittle stress-strain characteristics (2.5-4.8% elongation at break) and low creep at room temperature. As an interesting aside, claims have been made that up to 5% glass fibre by volume has been used successfully in sand-cement mortar without the cement and water clumping together (or ‘balling’).

Glass-fibre products exposed to outdoor environments have shown a loss of strength and ductility. It is speculated that alkali attack or fibre embrittlement are possible causes. GRC has been confined to non-structural uses, where it has wide applications. GRC has also been used as a replacement for asbestos fibre in flat sheet, pipes and a variety of precast products. GRC

CEMENT & CONCRETE

products are used extensively in agriculture, for architectural cladding and components, and for small containers.

Steel fibres Steel fibres have been used in concrete since the early 1900s. The early fibres were round and smooth and the wire was cut or chopped to the required lengths. The use of straight, smooth fibres has largely disappeared, and modern fibres have either rough surfaces, hooked ends or are crimped or undulated throughout their length.

Carbon steels are more commonly used to produce fibres, but fibres made from corrosion-resistant alloys are available.

Stainless steel fibres have also been used for high-temperature applications.

Steel fibres have high tensile strength (0.5-2 GPa) and modulus of elasticity (200 GPa), a ductile/plastic stress-strain characteristic, and low creep. Diameters (based on cross-sectional area) typically range from 0.1 mm to 2 mm, lengths from 7 mm to 75 mm, and aspect ratios from 20 to 100. (Aspect ratio is defined as the ratio between fibre length and its equivalent diameter, which is the diameter of a circle with an area equal to the cross-sectional area of the fibre.)

They have been used in conventional concrete mixes, shotcrete and slurryinfiltrated fibre concrete, where the content of steel fibre ranges from 0.25% to 2% by volume. Fibre contents of over 2% by volume generally result in poor workability and fibre distribution, but can be used successfully where the paste content of the mix is increased and the size of coarse aggregate is not larger than about 10 mm.

Steel-fibre-reinforced concrete containing up to 1.5% fibre by volume has been pumped successfully using pipelines of 125 mm to 150 mm in diameter. Steel fibre contents up to 2% by volume have also been used in shotcrete applications using both the wet and dr y processes, while fibre contents of up to 25% by volume have been obtained in slurr y-infiltrated fibre concrete.

Improved impact resistance Concretes containing steel fibre have substantially improved resistance to impact and greater ductility of failure in compression, flexure and torsion.

The elastic modulus in compression and modulus of rigidity in torsion are also no different before cracking when compared with plain concrete tested under similar conditions.

Steel-fibre-reinforced concrete, because of its improved ductility, could find applications where impact resistance is important. Fatigue resistance of such concrete is reported to be increased by up to 70%.

On a final note, optimising the fibre mix ratio is vital. If the fibre content of the concrete is too low, the fibres will not have a significant effect on the strength or modulus of elasticity of the composite. For this reason, mix designers must evaluate

THE USE OF FIBRES • Fibres should be significantly stiffer than the matrix – i.e. have a higher modulus of elasticity • Fibre content by volume must be adequate • There must be a good fibre‐ matrix bond • Fibre length must be sufficient • Fibres must have a high aspect ratio – i.e. they must be long relative to their diameter

published test data and manufacturers’ claims carefully.

“At the other extreme, high-volume concentrations of certain fibres may make the plastic concrete unworkable, which again underscores the need for specialist skills to achieve the best result,” Perrie concludes.

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CEMENT & CONCRETE The Saldanha Bridge’s deck has been strengthened with Sika CarboDur BC-16 carbon fibre rods, which have a tensile strength six times that of structural reinforcing

Carbon fibre reinstates Saldanha Bridge

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he application of specialist carbon fibre rods and an adhesive played a key role during the recent remediation of the Saldanha Bridge in the Western Cape. The bridge’s structural integrity was compromised due to miscalculations on the top-steel installation during initial construction.

The repair, which was carried out by RHDHV Engineers, together with main contractors Power Construction, was completed within

three weeks at an estimated cost of R2 million. The alternative would have been to demolish and rebuild the bridge at a cost of around R9 million over a six-month project duration.

The first step in the repair process entailed cutting 1.4 km of longitudinal slots into the concrete bridge deck. These slots were specifically created to carry Sika’s CarboDur BC-16 carbon fibre rods. Measuring 16 mm in diameter, these rods have a sanded finish to give added mechanical key and

exhibit a tensile strength six times that of structural reinforcing. This provides the ability to carry very heavy loads.

These rods were glued into place using Sikadur-30 epoxy mor tar and trowelled flush with the deck surface. Easy to mix and apply, this adhesive requires no priming prior to application and has high creep resistance under permanent loads.

On completion of the near-sur face mounted carbon fibre rod application, the subsequent road surfacing commenced.

InfraChamps Consulting is a 100% Black-Owned multi-disciplinary consulting engineering firm, providing a complete offering of professional engineering services. We have a full complement of highly professional skilled engineers, technologists, technicians and project managers with a combination of more than 30 years’ experience.

Our Company Memberships includes IMESA, SABTACO and our professionals are registered with ECSA, SACPCMP, SAICE, SAIEE and SAIMechE. Our Services are: • Civil Engineering, • Structural Engineering, • Transportation Engineering, • Water Engineering, • Building Services, • Project Management, • Electrical Engineering, • Mechanical Engineering.

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HEAD OFFICE 43 Montrose Street, Birchwood Court, Midrand, Gauteng Tel.: 011 655 7299 Email: info@infrachamps.co.za www.infrachamps.co.za We have offices in Gauteng, KZN, Free State and Eastern Cape.

WATER & WASTEWATER

Wise spring water use is essential As water levels in the Integrated Vaal River System (IVRS) continue to decline, calls to use water sparingly and wisely have intensified.

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he water levels in the main dam in the IVRS, the Vaal Dam, are a far cry from the roughly 70% capacity it recorded this time last year. Instead, water levels have plummeted below the 50% mark.

While many of the other dams in the IVRS are in a better position, they too have experienced a decline in their levels. The Mohale and Katse dam levels remain concerningly low. Mohale Dam has dipped below 13%, while Katse Dam sits just below 37%. The entire IVRS now sits at around 66.6%.

As the summer rainfall portion of the country enters spring, the declining dam levels highlight the importance of conserving water.

Water Wise recommends wetting your hands and turning off the tap while you soap your hands. Soap your hands for 20 seconds, making sure you clean your hands thoroughly, and only then turn the tap on to rinse. Dry your hands with a paper towel and throw the used towel in the bin.

To this end, communities should avoid water losses through leaking pipes and taps by fixing those in their yards and reporting municipal leaks to the local authorities. Behavioural change around water use is also critical during this period, so that the current water we have is conserved until the next rainy season in the catchment area.

Water leaks and non-revenue water can be very costly and are a large contributor to water wastage in South Africa. Households and businesses are encouraged to read their water meters and regularly test for leaks to help save both water and money.

Water Wise assists in educating the general public on how to read water bills so that there is a greater understanding of how much water is consumed in the home.

FOR MORE INFORMATION ON HOW TO BECOME WATER WISE, VISIT: facebook.com/WaterWiseRSA twitter.com/water_wise www.waterwise.co.za/site/home.html

A family of four in South Africa can use up to 1 200 ℓ/day of water in the home (300 ℓ/day/person). It has been estimated that the world average per capita water use is 185 ℓ/day – which means South Africans use significantly more water per person per day than the global average.

All water users – from bulk customers to business, local authorities and individual households – must use water efficiently and sustainably.

Water decline and Covid-19 As South Africa deals with the Covid-19 pandemic, the declining dam levels come at a time when water is essential for practising good hygiene. Rand Water, through its ‘Water Wise’ campaign, has called on the community to use water wisely and sparingly, to prevent any wastages, while maintaining good hygiene and handwashing practices.

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WATER & WASTEWATER

When lockdown necessitated the introduction of virtual audits, opportunities arose for innovation, improved processes and future methodologies.

By Danielle Petterson

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Virtual audits hold new opportunities

outh Africa’s Blue, Green and No Drop programmes received worldwide recognition for their incentive-based regulation approach. Although the Department of Water and Sanitation (DWS) has not enforced these programmes for several years, numerous municipalities and water utilities

WHY CONDUCT GREEN DROP AUDITS? • Drive consistency in performance and continuous progress in wastewater services management • Ensure legislative compliance for wastewater operations and management • Facilitate a competitive environment with incentive to excel and perform • Continuously identify gaps in knowledge, infrastructure, systems, coupled with external expertise to make recommendations to address the gaps • Forge proactive and informed planning • Ensure a high state of readiness as/when the DWS requires national audits to recommence

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have adopted the Green Drop (GD) audit criteria as an internal standard to measure and drive continuous improvement in wastewater management.

One such organisation is ERWAT, which provides bulk wastewater conveyance and treatment to thousands of industries and more than 3.5 million people.

A consortium appointed by ERWAT under a three-year contract has been conducting GD audits for the organisation. This consortium is headed jointly by Water Group Holdings and AHL Water, supported by specialist subconsultant Emanti Management, which provides IT and development support, and brings vast auditing experience to the table.

The consortium is responsible for: • quarterly GD audits of ERWAT’s 19 wastewater treatment works (WWTWs) • development, implementation and tracking of Wastewater Risk Abatement Plans • development, implementation and tracking of GD Improvement Plans for all 19 WWTWs • quarterly reporting of GD performance to top management and its municipal partners to ensure continuous improvement in the operation and management of the WWTWs • intermittent training as/where knowledge gaps are identified.

“We must applaud ERWAT for having a vision to continue with GD audits. In this

way, ERWAT continues to drive its internal performance objectives and remains in a state of readiness when the DWS announces continuance of the national GD programme,” says Marlene van der Merwe-Botha, director, Water Group Holdings.

Introducing the virtual audit The consortium’s final year 3 quarter 4 audits, for the period April to June 2020, fell during the nationwide Covid-19 lockdown.

Given the travel restrictions and social distancing requirements, remote auditing was the best option.

According to Ayesha Laher, director, AHL Water, specifications for remote auditing are already included in ISO 19011:2018 – Guidelines for auditing management systems. A remote audit includes all aspects of the conventional audit utilising internet platforms such as Skype or Zoom and cloud-based data sharing services such as Mimecast, Dropbox and OneDrive.

The team followed an approach of targeted verification audits, preceded by an online audit conducted on information shared online, as outlined in Figure 1.

According to Shawn Moorgas, director, Emanti Management, preparation was essential for the success of the virtual audit process. The consortium team wrote up a

WATER & WASTEWATER

protocol for the virtual audits and engaged with ERWAT to plan the way forward.

Prior to starting the virtual audit, the team established a database that captures all the information needed for each of the audit criteria along with the relevant portfolio of evidence. The ERWAT teams were given 1.5 weeks to populate the database, which was reviewed by the inspectors who drew up their first assessment scorecard. This was given back to the teams to review and prepare for the actual virtual audit.

“To maximise concentration and participation, we kept the virtual meetings to a maximum of 1.5 hours, focusing on key criteria within each scorecard, and each ERWAT team was given their own slot,” says Moorgas.

Photos were key to the virtual site inspection. Two Inspectors, along with works personnel, performed a walkthrough, completed forms, and raised questions for the lead inspectors. The photos were uploaded for review and discussed during the virtual meetings. The team believes further opportunities exist to use video in the future.

“If you take enough pictures, you can be anywhere in the world and see the challenges a WWTW is facing. And it provides you with a means to benchmark faults for review in the next site inspection,” adds Moorgas.

ERWAT personnel, with 90% indicating a score >8/10 (with 1 being poor and 10 being excellent).

Feedback indicated, among others, that the virtual audits promoted increased understanding of the GD requirements and information required, forced improved data quality, reduced the burden of storage and transport of hard copies of information, contributed to building institutional memory with a centralised cloud-based database, increased participation, and allowed auditors sufficient time for the process.

Furthermore, the provision of draft scorecards before the actual audit provided plant personnel with the opportunity to evaluate scores and identify discrepancies, while targeted verification provided a platform to discuss discrepancies and why criteria were not met. Lastly, it promoted continuous improvement as plant personnel are given a second chance to submit outstanding information.

The biggest drawback for most respondents was a lack of face-to-face interactions with the audit team, which present opportunities to gain knowledge and improve understanding on a broad spectrum of components related to wastewater treatment.

Connectivity at some plants, poor sound and signal interruptions were some of the biggest challenges faced during the process.

Challenges and feedback

Possibilities for the future

Overall, the process was a resounding success. The virtual audit approach received an overwhelmingly positive response from

The team agrees that virtual audits hold great promise for the future, post lockdown.

Although the process is data hungry, huge

savings in time and travel can be achieved.

Locally, virtual audits can optimise cost, but they also present the opportunity to extend audits outside of the country, without the need to travel.

Moving for ward, Laher proposes the following format for both online and faceto-face audits: • plant personnel upload data on a cloudbased platform • inspectors conduct an online audit and send scorecards to plant personnel for interrogation • the audit team and plant personnel participate in a structured one-hour faceto-face audit to discuss discrepancies and opportunities for improvement • plant personnel are given an opportunity to submit additional information • moderation and submission of final scores.

Van der Merwe-Botha reports significant interest in the virtual audit process from the sector. However, she stresses that virtual audit protocols must be well documented and shared among peers, to increase uptake and ensure quality services.

“This is a new type of professional service and we as auditors need to expand our skills, understand the various platforms available, and learn how to better facilitate the process. This could even be the way forward for the DWS given the limited budget and skills available. There are increasing calls for the reintroduction of the Drop reports, and it is only a matter of time,” concludes Van der Merwe-Botha.

FIGURE 1 Virtual Green Drop audit methodology

DATA COLLATION

ONLINE AUDIT

TARGETED VERIFICATION AUDIT

VIRTUAL SITE INSPECTION

• Audit team provided list of required information per KPI: file name, criteria, requirements, examples • Client upload data on internet platform per KPI: OneDrive

• Audit team conduct online audit using data provided by client • Audit team meet to discuss outcomes and key issues for clarity • Scorecard shared with client • Client to review and communicate all discrepencies to audit team • One hour online audit session with audit team and plant personnel to discuss key findings and discrepencies in scores • Conducted via audio or video tools: Zoom or Microsoft Teams • Consolidation of final scorecard by audit team • Live virtual tour • Audit team to use previous site inspection for reference • Plant personnel to conduct virtual tour using smartphone • Audit team to request visual proof of specific KPI • Audit team to complete site inspection form • Photo assigment: same as above, but plant personnel provide photographic evidence

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WATER & WASTEWATER

Stortemelk Hydropower Project

Ensuring SA’s water security

Water security appears regularly in the top five global economic risks. With increasing pressure from economic and population growth, climate change, land-use changes, declining water quality and catchment degradation, South Africa’s water security is increasingly at risk.

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outh Africa has always been a water-stressed country and, as a result, has developed a complex and highly integrated bulk water distribution system. The country’s water-resource expertise and legislation are respected globally.

“Investing in technical and institutional capacity, improved operations, water-use efficiency and the development of decision support systems is particularly important as we become increasingly dependent on these more complex and stressed water supply systems,” notes James Cullis, technical director, Zutari.

“We also need to balance the trade-off between competing demands for an increasingly scarce resource. Financial constraints and a lack of capacity and accountability for the management of our water resources require innovative solutions, particularly in Africa.”

James Cullis, technical director at Zutari

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SA’s water future There are still significant opportunities for improved water-use efficiency through replacing old pipes, reducing leaks, and by implementing new technologies such as lowflush toilets, improved irrigation systems, and pressure-management devices. Cullis believes smart technologies, improved monitoring, and operational decision support systems are also critical to reduce wastage.

The future will see a transition to more diverse and alternative water supply options. In particular, the increased reuse of wastewater for both direct and indirect purposes offers many advantages. Demand management will, however, continue to be an important component for managing the variability of water supply.

“It is clear that the private sector will have an increasing role in coming up with long-term water solutions,” Cullis adds. Trends include a general move towards more decentralised water supply and treatment solutions – similar to what is happening for energy – but the private sector will also be critical in terms of providing the financing as part of public-private partnerships for water.

A sector leader Zutari is a major player in the water sector, with its water engineering services grouped into five main practice areas: water resources (including flooding and stormwater); bulk

infrastructure (pipes and pump stations); dams and hydropower; water, wastewater and industrial treatment; and water for industries (including mining).

“We have undertaken water resource planning and feasibility studies for alternative water supply options, including deep groundwater aquifers, desalination and direct and indirect potable reuse. We are also assisting municipalities in terms of access to financing, development of their digital transformation strategy and the development of decision support systems to improve operational efficiencies and reduce losses,” says Cullis.

Zutari has undertaken the design and construction supervision of many large bulk water supply systems. Other areas of focus include hydropower, hydrology, water resource planning and feasibility studies, stormwater and flood modelling support, mine water balances, and treatment and bulk water conveyance for the mining sector.

“We maintain one of the largest groups of professional water engineers in South Africa, if not Africa,” Cullis highlights. At present, Zutari has over 200 water professionals in Gauteng and Cape Town, with regional offices in all the major metros in South Africa, and in various other countries in East, West and Central Africa.

The company is a trusted advisor to major municipalities, water boards and water utilities. Notably, it is currently the international support consultant developing a water resource plan for the Ministry of Water and Irrigation in Kenya. Zutari has also contributed to numerous national and regional climatechange studies, including the Long-Term Adaptation Scenarios (LTAS) flagship research programme and the CSIR’s Greenbook for climate risk for municipalities.

WATER & WASTEWATER

NEW NAME, SAME COMMITMENT

Meulwater Water Treatment Works

Leliefontein PumpAs-Turbine Station

Zutari has designed some of the region’s most significant bulk water infrastructure solutions, including the Berg River Dam, the Vresap pipeline, the Lower Thukela Bulk Water Supply Scheme, the Olifants River Water Resources Development Project, the Mokolo Crocodile Water Augmentation Project, the Lesotho Highlands Water Project, and Maguga Dam in eSwatini.

Many projects have won awards for innovation, with the most recent including the Stortemelk Hydropower Plant, the Leliefontein pump-as-turbine water-energy solution, and the Meulwater and Preekstool water treatment plants.

Barely a month after the historic Sustainable Infrastructure Development Symposium of South Africa, Zutari launched in the infrastructure space with a primary focus on engineering impactful infrastructure projects in Africa.

Formerly known as Aurecon, Zutari emerged following a bold decision by the owners of Aurecon Africa in October 2019 to demerge from the global business, headquartered in Melbourne, Australia.

The name Zutari is derived from the Swahili words for ‘invent’ and ‘nectar’, namely mzulia and nectari.

While no one saw the Covid-19 pandemic coming, Zutari CEO Dr Gustav Rohde notes that management could already see the winds of change push back against globalisation as early as September 2019. “We could see the market changing, and so decided to demerge from the global company to be proudly African.”

Tracking water consumption is made easy by Water Wise

The Department of Water and Sanitation (DWS) aims to reduce water demand and increase supply to our growing population and economy to ensure water security by 2030. Currently, our waterstressed country faces economic water scarcity due to issues with the country’s water infrastructure, an ever-increasing demand on a limited supply and other environmental factors.

leaks, which can be easily detected if households monitor their water use by taking regular water meter readings. To assist people with this, Rand Water’s environmental brand, Water Wise, has developed a Water Wise calculator, which serves as a simple tool to estimate household water use and assist people in detecting high water-use activities and even leaks. The calculator, through a question–answer system, generates a water usage chart and an estimated cost (R) of the household’s water bill in a month. This estimated value should not be used to dispute municipal bills, however, as the value generated is based on general South African water use statistics. This calculator aims to assist the end-users to be responsible in ensuring optimal use of the water they receive.

Keeping track of water usage through the Water Footprint Assessment, founded by Arjen Hoekstra, is a step in the right direction that shines light on water use patterns in different aspects of society.

With a deeper understanding of water consumption patterns and water balance, water utilities and municipalities can work towards improving their existing water-supply models, as well as addressing Achieving this will contribute to the bigger picture water wastage such as non-revenue water, and excessive use and leakages, in order to reduce of reduced water demand, ensuring a sustainable supply water losses in large distribution networks. of water for South Africa.

End-users such as homeowners also encounter

www.randwater.co.za and click on the Water Wise logo FOR FURTHER INFORMATION ON WATER WISE, PLEASE CONTACT US ON: 0860 10 10 60

WATER & WASTEWATER

Installation of water and sanitation infrastructure within impoverished communities

Water hyacinth surge in rivers due to excessive nutrients from inadequate wastewater treatment

Bosch Munitech works towards a sustainable future South Africa is facing an increased frequency of extreme weather events due to climate change. As a result, there is a greater threat of vector-borne diseases and food, energy and water insecurity, which threatens livelihoods.

vulnerable municipalities in South Africa are rural villages, small towns and secondary cities.

“Vulnerabilities of these municipalities are expected to increase due to the high levels of informal housing and the lack of efficient management of these growth areas. Rural areas are particularly vulnerable due to their dependency on climate-sensitive resources, such as water and an agrarian landscape,” says Moodley.

Climate change and water

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s temperatures over Africa increase more rapidly than the projected rise of global temperatures, the region is likely to experience a more drastic impact due to prevalent socio-economic issues.

“It is critical that South Africa responds to these challenges by urgently introducing programmes that include legislative reform, revision of pollution limits, proactive planning by local authorities and the launch of sectorspecific controls,” says Keshan Moodley, director, Bosch Munitech – a member of the Bosch Holdings group of multidisciplinary consulting engineering companies.

“The process of tackling climate change symptoms is difficult and complex; however, a reduction of past and future climate change is achievable via holistic thinking in terms of technical, social and monetary requirements, as well as a responsible industrial and commercial sector, backed by proper policy and implementation by government and the private sector.”

According to government’s latest Financial and Fiscal Commission report, the most

Climate change negatively affects water availability and quality, which in turn, has a negative impact on community health. By ensuring continuous access to safe drinking water, the health impacts from waterborne diseases can be greatly minimised.

Bosch Munitech’s mitigation measures for water scarcity – water conservation and demand management projects – include municipal leak detection, the upgrading of aged infrastructure and the installation of new infrastructure. The company also recommends logging water flows to determine the demand on the water supply networks and studies on how best to reduce water usage and wastage by consumers.

Wastewater treatment works (WWTWs) that release treated effluent into rivers and oceans need to be monitored in a more proactive way, as it is now evident that viruses such as SARS-CoV-2 are transported in sewer systems. Recommended monitoring methods include scheduled sample and laboratory analysis. Sensors should be installed on effluent valves to establish if, and when, they need to open for release, especially in periods of high rainfall.

Monitoring should also include wateruse licence evaluations, which consider

the testing of the effluent and the river environment into which it is released. The development of educational material and workshops for adults and children is also needed to promote water conservation and change mindsets.

Climate change poses both opportunities and threats to the wastewater reclamation sector. Processes that occur in WWTWs are affected by extreme weather events, which lead to untreated sewer overflows and increased flooding. Wastewater reclamation and reuse are becoming more promising means to conserving valuable fresh water sources, while increasing the efficiency of material utilisation.

Planning for resilience In light of the increased occurrence of severe weather events, Bosch Munitech encourages municipalities to adapt their infrastructure planning to encompass more resilient and adaptive asset management practices in line with climate change, for more reliable forecasting of long-term infrastructure planning.

With a thorough understanding of the interactions between human activities and natural processes, the Bosch Munitech team assists the public and private sector to integrate climate change adaptation strategies into asset management practices.

This is achieved mainly through risk assessments, life-cycle management projects and improved levels of service.

As a solutions-driven utility management company, Bosch Munitech provides specialist ser vices in the municipal water and wastewater sectors, as well as for solid waste, environmental and asset management, utilities detection and laser scanning of buildings, factories and structures.

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WATER & WASTEWATER

Project management – the key to service delivery South Africa is a water-scarce countr y and the management of its water sources as well as related supply and treatment infrastructure will always be a critical priority.

By Leslie van Zyl-Smit*

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he recent drought conditions experienced in large parts of South Africa have had a negative impact on water supply, as well as most sectors of the economy, including agriculture, industry, tourism and food security.

As part of the South African government’s drought relief measures, numerous projects throughout the country have been fasttracked as so-called ‘emergency water supply interventions’, in an attempt to alleviate the desperate need of communities that have been affected by the drought conditions. Due to the time constraints on these projects, work is often implemented without sufficient engineering design, project management or budget allowances.

These emergency project implementation scenarios remind one of a well-known project management saying: “Good, cheap, fast – you can pick any two.” Implementing projects as an emergency by default implicates fast turnaround times, which leaves clients with the option of choosing between “good” or “cheap” solutions. If one throws into the decision-making process a limited budget, these so-called emergency projects are doomed to be classified as “cheap” and “fast”.

South Africa, like the rest of the world, is facing unprecedented socio-economic challenges, as communities and leadership struggle to come to terms with the devastating aftermath of the Covid-19 pandemic.

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For the unforeseeable future, funding for capital projects will be strained due to the costly measures implemented in mitigating the impact of the pandemic and we can illafford implementation of “cheap” and “fast” solutions when it comes to infrastructure needed to provide much needed basic services. Although the desperate drought conditions left many communities with no alternative but to implement emergency measures, such projects should be limited at all cost.

Another kind of drought Unfortunately, it is not only projects given emergency status that currently suffer from inadequate project management and engineering design within the South African water services sector.

Apart from the lack of annual rainfall, South Africa is also experiencing a drought in the

form of a skilled and experienced workforce.

This is especially true when it comes to technically demanding disciplines involved in providing complex engineering and project management solutions.

Recent years have been known for the mass exodus of skilled resources from the country and an overemphasis on the social cultures within organisations have come at the cost of a much-needed technical culture that fosters work ethics and skills development. To a large degree, we have lost the technical ability to develop and implement long-term planning strategies in the form of water services development plans, and few resources are skilled enough to apply supply chain management procurement regulations and contract data.

The way forward With the Covid-19 pandemic reaching its peak, many of us have much time at hand to reflect on the way we do business and implement projects within the South African context. There is no short-term, quick-fix solution to the challenges faced by project teams implementing waterrelated infrastructure.

Perhaps it is time to get back to project management basics by consulting expert judgment and focusing on the phase gates that define project

WATER & WASTEWATER

life-cycle stages. According to the Project Management Body of Knowledge best practice guidelines for effective project management, the following knowledge areas are applicable to the successful initiation, planning, executing, monitoring and control, as well as project close-out processes applicable to any project: • integration management • scope management • cost management • schedule management • quality management

• resource management • communications management • risk management • procurement management • stakeholder management.

The effective management of the above knowledge areas is traditionally the responsibility of the employer (delegated to the employer’s agent or representative or engineer depending on the condition of contract). However, where engineering design and project management services are not provided to required standards,

contractors are forced to take up much of the management responsibilities in an effort to mitigate project risk and ensure effective project implementation.

Therefore, in an attempt to ensure sustainable operations, wise contractors are investing in professional, in-house design capacity, as well as resources able to provide project management and contract administration services.

South Africa can no longer afford not to deliver on much needed basic services to its communities. Contractors can contribute to project management requirements in many ways; however, it remains the responsibility of the employer to ensure effective stakeholder, procurement and scope management.

Let’s get back to the basics of sound engineering design, planning, project management and costeffective implementation of sustainable water solutions. *Leslie van Zyl-Smit, Pr Eng, Pr CPM, PMP, is a director at REDE.

A century of true impact.

Our past has seen us operating under different names: Ninham Shand, Africon, NETGroup, Aurecon. A nearly one-hundred-year journey that now, in 2020, sees us becoming Zutari.

As a broad collective of engineering consultants and trusted advisors, we look forward to continuing to co-create a thriving Africa.

PUMPS & VALVES

Pressure reduction solution Pressure management and reduction is essential to ensure the safe and efficient use of water in both municipal and industrial applications.

The pressure reducing station has been working effectively since 2017

A

s pioneers in water supply protection and efficiency, Bermad’s proven water and control management solutions include state-of-the-art hydraulic control valves, air valves and advanced water meters.

The company recently installed a pressure reducing system, ensuring a fail-safe solution for a client in Norway.

Pressure reduction solution The client is Yara International, a global company based in Norway that specialises in agricultural products and environmental protection agents.

At Yara Norge AS in Glomfjord, Norway, the company needed a simple, fail-safe hydraulic solution for 24/7 water supply. The full redundancy pressure reducing system required valves able to reduce pressure to required levels through two separate lines, even in the case of a catastrophic failure.

Water from a small reservoir enters the production process in two branches – one for each of two production sectors. The DN 400 branch runs at a static 16.9 bar, with a 15.0 bar minimum. The flow range is never less than 300 m3/h, 500 m3/h on average, and up to 1 000 m3/h at its max. The DN 700 branch has similar pressure ranges, but the flow range is 2 000 m3/h to 4 000 m3/h, and the nominal flow is 2 500 m3/h.

Yara needed a simple hydraulic solution in the case of massive pressure differentials because production only requires 6 bar to

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The simple hydraulic solution manages massive pressure differentials

7 bar. Bermad was selected because of the need for safety, reliability and functionality in a 24/7 operation and to endure the high pressures involved and high flow expected in a critical situation.

The Bermad team worked with Yara engineers to create two separate, redundant pressure reducing stations for the DN 400 and DN 700 branches.

At the DN 400 branch pressure reducing station, the solution included a standard 400 mm pressure reducing valve (PRV), a backup 400 mm PRV, and a 50 mm air valve.

There is an additional 100 mm air valve and a 400 mm safety relief valve to meet Yara’s redundancy requirements in a highflow environment.

To account for the high pressure and increased flow of the DN 700 branch, there is a larger 150 mm air valve and 700 mm models of the standard PRV, safety relief valve and the backup pressure releasing valve.

The method of operation for the two is similar. The standard PRV reduces This valve ensures constant downstream pressure of 7.8 bar

downstream pressure from 15 bar to around 7 bar. The backup PRV is ready in case of a potential failure in the primary valve. Finally, the safety relief valve is in the fully closed position and can open momentarily in the case of excessive pressure within the system.

The two pressure reducing stations were commissioned in just three days, and the system has effectively managed over-pressure situations at the Yara Norge AS facility since 2017. The system has successfully proven itself. When fractured cartridge filters broke apart and were lodged in the PRVs, the pressure relief system functioned as planned and protected the downstream pipe system.

Local partner According to Rowan Blomquist, CEO, Macsteel Fluid Control, PRVs offer a way to easily and cost-effectively control the maximum pressure entering a zone.

“In a country like South Africa, which loses millions of litres of water every year due to pipe leaks and bursts, effective pressure control is of the utmost importance.

The common factor in every water system is the fact that leakage is driven by pressure. Reduce the pressure, even for a short period, and you reduce water leakage.”

As the local supplier for Bermad products, Macsteel Fluid Control offers a wide range of PRVs and cost-effective solutions for any pressure management issue that can help utilities to protect their water supply.

INSIDE Tackling the drought

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Niche infrastructure delivery

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Reindustrialising Buffalo City

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Civil suite software

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Tapping the Coegakop wellfield

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Roads to economic growth

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Bridging communities

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Power by design

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Achieving water security through 4IR

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NELSON MANDELA BAY & BUFFALO CITY

Nelson Mandela Bay Municipality (NMBM) is hard at work to bolster its water supplies and conserve its resources as the city battles the ongoing drought.

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elson Mandela Bay is reportedly using 40 Mℓ more than the target of 250 Mℓ a day as the city’s combined dam capacity reaches a low of 17%. Restrictions on water extraction from supply dams are as high as 70% as the metro continues to face a disastrous drought.

Combatting losses In an effort to reduce water losses, the city introduced a R15 million water leaks project earlier this year, along with a commitment to pursue a tight turnaround time of 12 hours for the attendance of leaks.

The project saw seven plumbing companies appointed to eradicate the huge backlog of 15 000 reported water leaks across the metro. The metro loses 28% of its total potable water to leaks every month.

In addition, the metro’s newly appointed head of Infrastructure and Engineering, Mongameli Bobani, recently announced that flow meter restrictors would be installed to throttle water supply to customers with high consumption. Industrial, commercial and institutional users will also be requested to reduce their consumption by at least 20%.

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Water levels in Kouga Dam, the region’s main supply dam, have dropped below 7%

TACKLING THE DROUGHT The municipality has also undertaken an upgrade of the Motherwell-Chelsea 500 mm pipeline. The badly corroded pipeline was causing frequent water outages affecting the western part of the bay.

According to Barry Martin, director: Water and Sanitation, NMBM, the pipeline is almost 60 years old and the municipality had identified a critical area of the pipeline that had reached the end of its lifespan. The replacement of a section of the pipeline forms part of the metro’s broader plans to find longterm solutions to water supply challenges.

The upgraded pipeline will assist with transporting water from the Nooitgedacht scheme, which has been upgraded to bolster water supply.

New build Part of NMBM’s drought response involved infrastructure upgrades and new builds.

This includes the upgrading of the Nooitgedagt Water Treatment Works (WTW), which is being upgraded from a 140 Mℓ/day to 210 Mℓ/day capacity.

Phases 1 and 2 have been completed and included the upgrading of the incoming electrical supply, civil, mechanical and

electrical works for six new filters and a low-level pump station. Phase 3 includes civil, mechanical and electrical works for clarifiers, installing new filters, and the construction of a 45 Mℓ reservoir that will go into operation upon completion of the treatment plant.

Interim Executive Mayor Cllr Thsonono Buyeye noted that the plant upgrade would bolster water supply from the Nooitgedagt scheme. “The key is to make sure that the amount of water we can extract from this scheme is maximised to the fullest,” he said.

The city is also busy with the construction of the Coegakop wellfield and WTW, which will harness groundwater to bolster supplies.

“This project is key for us as we will be able to extract as much water as we possibly can from underground sources, as we continue to address challenges in the city,” said Buyeye.

The R260 million project will produce 26 Mℓ/day to augment NMBM’s current water supply sources and is expected to lift some burden off of the Nooitgedagt WTW. Once completed, the Coegakop wellfield and WTW will be the largest biofiltration plant in South Africa.

NELSON MANDELA BAY & BUFFALO CITY

In delivering his 2020 State of the City Address, Buffalo City Executive Mayor Xola Pakati noted that the city’s Metro Growth and Development Strategy (MGDS) remains a key focus, as the municipality works towards building a well-governed, connected, green and innovative city by 2030.

T

he creation of resilience for the economy of our metro is predicated on our purposeful implementation of our economic strategy – the MGDS. The strategy is anchored on two interrelated economic approaches: first, consolidating our status as an automotive city including deepening the local supply chain impact; and second, diversifying our economy into new growth sectors and industries,” said Pakati.

In the automotive sector, Mercedes-Benz South Africa (MBSA) has been implementing a major expansion plan, built around the new C-Class model, which will see production run from 2021 to 2027. This production cycle will bring an investment of more than R10 billion for the city along with a 30% increase in production capacity and jobs.

Pakati noted the many local supply chain benefits of this, with 30 local suppliers linked to the new model. Buffalo City is also trying to ensure that at least 25% black-owned companies are among the second- and thirdtier suppliers as targeted in the South African Automotive Masterplan.

“As a municipality, we have been supporting this expansion through land availability and speedy processing of land and building applications. We are also working closely with MBSA and the East London IDZ (ELIDZ) on logistics needs and have designed the necessary road infrastructure. We have also worked closely with the auto industry to ensure that load-shedding does not affect just-in-time suppliers,” added the mayor.

On economic diversification, the city has focused on tourism, agro-industry, ICT and global business services.

Reindustrialising Buffalo City Executive Mayor Xola Pakati, Buffalo City

“At the heart of this is a new approach away from narrow investment promotion to active investment facilitation. Part of this approach is to better understand the constraints faced by business, and to try and address these constraints working alongside the three spheres of government,” explained Pakati.

The municipality is working to retain its industrial base, rather than narrowly focusing on new investment. As part of the efforts to reverse deindustrialisation, the city has provided rates and electricity subsidies to firms such as Defy to retain and expand their presence.

Responding to Covid-19 Pakati went on to note that the Covid19 pandemic is accelerating the country’s smart, green transition, and that Buffalo City is well placed to leverage this change.

“We have a competitive advantage in a number of sectors and industries that have been identified for intervention and reforms.

These include renewable energy, automotive manufacturing, pharmaceuticals, agriculture and agro-industry, tourism, the creative industries, and the digital economy,” he said.

The focus in the short term will be on infrastructure-led recovery, and Buffalo City has developed several shovel-ready road, energy, ICT, industrial infrastructure, sanitation, water and human settlements projects. The municipality’s infrastructure delivery system is also being strengthened to ensure readiness and greater efficiencies.

Part of developing this infrastructure pipeline is a more deliberate prioritisation of social and economic value to enable and position these projects for the investment market. Here, the city is working closely with the ELIDZ on port logistics, energy, agro-industry and ICT projects, and the Buffalo City Development Agency on renewable energy, tourism and property developments.

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COEGA’S EXPERTISE IN INFRASTRUCTURE PROJECT MANAGEMENT WILL HELP SOUTH AFRICA FAST-TRACK ECONOMIC RECOVERY AMID COVID-19 PANDEMIC

The TASEZ was launched in 2019 and the success of it is important to the economic growth of the Gauteng Province. In the 2019 Gauteng’s State of the Province Address, the Honourable Premier David Makhura stated that: “we must be more aggressive and decisive in pushing a vision of turning the entire province into a single, multitier, mega special economic zone, based on Hannan, an island province in China, which is an SEZ in itself.”

The TASEZ is “Africa’s First Automotive City” and a key driver of economic growth in the City of Tshwane and the rest of the Gauteng province, with a mandate to promote economic participation for SMMEs and to create decent employment in the region.

A multi-billion rand Tshwane Automotive Special Economic Zone, a project by the Gauteng Province, Department of Trade, Industry and Competition, and City of Tshwane.

The Coega Development Corporation (CDC), developer and operator of the Coega Special Economic Zone (SEZ), recently announced that it has been appointed as the Implementing Agent (IA) to develop and operate the Tshwane Automotive Special Economic Zone (TASEZ). The CDC, as a public entity, is the IA of choice in the country due to its unparalleled expertise in mega and complex infrastructure development projects, says Dr. Ayanda Vilakazi, CDC’s Head of Brand, Marketing and Corporate Communications.

The multi-billion-rand TASEZ will mark an important milestone for the Gauteng Province, City of Tshwane and the Department of Trade, Industry and Competition (“the dtic”) SEZ programme. “SEZs are a catalyst for employment, transformation, socio-economic development and inclusive industry growth,” says Dr. Vilakazi.

“The CDC’s appointment demonstrates our resilience as an organisation, having secured this multi-billion-rand TASEZ project under a difficult operating environment, amid the COVID-19 pandemic,” added Dr. Vilakazi. The CDC provides expertise in the fast and efficient delivery of minor and mega complex infrastructure development projects in South Africa and the rest of the African continent. In addition, Coega has ISO certified systems and processes that guarantee the effective delivery of these projects within scope, time, and budget.

“Our record of unqualified audit opinion by the Auditor General of South Africa (AGSA) on our projects speak for itself. The national government and various provincial government departments trust the CDC with its multibillion-rand infrastructure projects. This has become even more pronounced amid COVID-19 and the need to fast-track economic recovery through infrastructure development and thus, stimulate job creation,” said, Dr. Vilakazi.

“The TASEZ development will create an influx of economic activity to the region as well as generate socio-economic benefits for both local communities and SMMEs in the following industries: Security; ICT Maintenance; Facilities Maintenance; Construction; Automotive Supply Chain; Marketing and Advertising; Catering and Events; and Information and Technology (among others). Both Job Seekers and SMMEs are encouraged to take advantage of these opportunities. For more information on the TASEZ, visit www.tasez.co.za. The TASEZ will also provide social development through the improvement of infrastructure and the provision of facilities not currently available within the area,” said, Dr. Vilakazi.

TASEZ is an attractive world-class automotive city and a preferred investment destination for the automotive industry on the African continent. Its proximity to an established automotive industry in Tshwane allows for increased economies of scale and scope, thereby lowering the cost of doing business. The SEZ offers worldclass customised solutions, incentives, support services and systems for manufacturers seeking excellence, and a productive and progressive location.

As a catalyst for employment, transformation and socio-economic development and inclusive industry growth, it boasts the most skilled labour in the sector, provides easy access to a strong consumer base, and connectivity to both suppliers and potential markets, while promoting export-orientated industries and local integration. Furthermore, the TASEZ provides unparalleled connectivity and harmony between the living city, green city and the productive city of Tshwane including an array of state-of-the-art modern infrastructure and facilities. It provides direct and ready linkages to regional and international markets, making exports easy to the Southern African Development Community (SADC).

“I am certain that the CDC will succeed in assisting the TASEZ to achieve its goals and strategic objectives,” remarked Dr. Vilakazi. The CDC’s role of helping to develop effective and efficient SEZs has become very important in South Africa and on the continent.

According to Dr. LI Yuanchao, former Vice President of the People’s Republic of China, during his visit to CDC in

November 2016: “I’ve been to many developing countries and industrial development zones around the world, the Coega IDZ is one of the best that I have seen.” These sentiments were echoed by the British High Commissioner to South Africa, Mr. Nigel Casey, in his remarks in 2017 about the Coega IDZ, when he highlighted impressive developments at Coega: “I’m particularly pleased by the number of investors who have taken advantage of this amazing economic zone and made a great success of their investments.”

The CDC is taking full advantage of the Inter-Africa trade, which has been made possible by the signing of the Africa Free Trade Agreement by African countries to promote greater economic integration across the continent. To this end, the CDC’s International Business under Coega Africa Programme is managing the implementation of infrastructure projects in Zimbabwe, Central African Republic, and Cameroon, amongst other countries.

CDC Successes: The CDC won a prestigious DTIC’s Investor of the Year Award in 2019 for its exceptional performance in attracting investments as well as excellence in developing and operating the Coega Special Economic Zone.

The CDC, with its proven track record in infrastructure implementation and programme management spanning over two decades, has successfully delivered other infrastructure projects in the country within budget, time and scope. The organisation has an arsenal of systems developed to fast track the implementation of infrastructure development projects whilst ensuring the creation of jobs and transforming economies through developing emerging businesses. The CDC’s Infrastructure Project Management Services include: • Project methodology and system; • Development of reporting & monitoring services; • Integrated planning & budgeting; • Development of business plans; • Stakeholder analysis & engagement programmes; • Procurement of service providers and required equipment; • On-the-job training & contractor development; • Human capital solutions; and • Post-implementation monitoring and facilities maintenance.

Furthermore, its performance has been independently verified by Statistics South Africa (STATS SA) that recently issued a report on the Coega SEZ: http://www.coega.com/DataRepository/Documents/ VonPSjxRuIRlNL1cFcRxeWCyy.pdf STATS SA’s report shows that the total income of the Coega SEZ tenants improved by 22% over the comparative period (2015/16 - 2018/19) indicating an increased contribution of tax returns from the tenants.

The Coega SEZ tenants also improved greatly on the net profit before tax, recording R506 million in 2018. The number of jobs increased by 17.3% on average per year.

The Coega SEZ contributed to the economy of the region by creating decent jobs with an average salary of R222, 000 improving from R218, 000 per employee in 2015; Coega has outperformed the East London SEZ on many key performance indicators and is assisting other SEZs in the country for the benefit of South Africa.

The drive for growth and development has made Coega not only one of the most successful SEZs in the country and the number one SEZ on the African continent, but an attractive and ideal investment destination for Foreign Direct Investment (FDI) and one of the country’s leading infrastructure Implementing Agents.

INFRASTRUCTURE DEVELOPMENT PROJECT: Kingsburgh Primary School - Lovu Town -in KwaZulu-Natal.

The CDC also offers mega and complex infrastructure project expertise and strategic solutions to the Eastern Cape Department of Public Works and Infrastructure; National Department of Public Works; National and Eastern Cape Department of Health, amongst others.

Lusikisiki Village Clinic opened by the President of SA, H.E. Cyril Ramaphosa, on 17 September 2019.

www.coega.co.za

For more information on the CDC’s Project Management Services, please contact our expert in Infrastructure Project Management, Mr. Chuma Mbande on +27 12 451 8300 (Pretoria Office).

BBBEE LEVEL 2 CONTRIBUTOR ISO 9001:2015 ISO 14001:2015 ISO 45001:2018 ISO 20000-1:2011 ISO 27001:2013

Nelson Mandela Bay Municipality has embarked on a series of drought intervention projects designed to ensure future water security. Two of these are currently being constructed by multidisciplinary contractor Stefanutti Stocks, namely the Nooitgedagt/Coega Low Level Scheme: Phase 3, and the Coegakop Biofiltration Water Treatment Works – the latter in consortium with PCI Africa.

T

he Eastern Cape region has experienced arid conditions for decades. More recently, though, the problem has worsened into an extended drought that poses a threat to the regional economy. In response, emergency water master plans have been developed to mitigate and manage immediate and longerterm scenarios.

One of the key focal points is Port Elizabeth, the province’s largest city and the administrative capital of Nelson Mandela Bay Municipality (NMBM), which extends to include the towns of Despatch and Uitenhage, the latter being one of South Africa’s major automotive manufacturing hubs.

As part of a longer-term response strategy, NMBM appointed Zutari (previously Aurecon South Africa) to develop a Drought Mitigation and Action Plan.

The Water Reconciliation Strategy Study for the Algoa Water Supply Area, published in

Biofiltration: A diagrammatic explanation of the process engineering workflow required to remove the iron and manganese concentrations in the groundwater abstracted at the Coegakop wellfield

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IMIESA August 2020

Bulk earthworks in progress at the Coegakop WTW, with the boundary wall and access road already constructed

Tapping the Coegakop wellfield

2008, identified groundwater as a future water supply option. In 2010, the decision was made to fast-track the viability of groundwater as a potential emergency supply option. In the interim, specific initiatives were approved, including the Nooitgedagt/Coega Low Level Scheme. The third and final phase of the scheme is currently being constructed

by Stefanutti Stocks for NMBM. Amatola Water was appointed by the Department of Water and Sanitation (DWS) as the implementing agent. The project started in May 2017 and is scheduled for completion in July 2021.

Nooitgedagt Situated just north of Port Elizabeth near the Addo Elephant Park, the Nooitgedagt Water Treatment Works (WTW) Phase 3 work entails the treatment capacity being upgraded from 140 Mℓ/day to 210 Mℓ/day. A 45 Mℓ storage reservoir has also been constructed during this phase to accommodate the extra capacity. Additionally, the scope includes some rehabilitation work and cathodic protection of the existing pipe supply system.

Orange River water is delivered to the plant via the Orange-Fish Scheme (Darlington Dam and canals) to the Scheepersvlakte Dam. From there, it flows by gravity pipeline to the Nooitgedagt WTW. Thereafter, the water is treated then gets pumped to the existing 10 Mℓ reservoir, and the newly constructed 45 Mℓ reservoir.

Prime groundwater targets “Similar to Cape Town’s Day Zero experience, NMBM’s strategy combines the need for greater conservation management with consumer education to lower demand, so we can preserve current resources while developing reserve capacities to meet future drought contingencies and growth projections,” explains project engineer Edzard Verseput, Infrastructure & Engineering: Water & Sanitation, NMBM. Groundwater abstraction is now officially on board and will supplement NMBM’s current consumption of around 300 Mℓ/day.

Like Cape Town, the greater Port Elizabeth area is underlain by Table Mountain sandstone containing extensive artesian aquifers. In

NELSON MANDELA BAY & BUFFALO CITY

A satellite map showing the site for the WTW, the location of the five boreholes feeding the plant, and the downstream Coegakop reservoir. The water then travels to the Motherwell reservoir

The WTW building features an integrated design to maximise security and minimise vandalism. The build’s windows on the upper level are screened by honeycombed brickwork, while the glazed sections of the roof are recessed

Port Elizabeth’s case, geophysical surveying and groundwater exploration drilling began in earnest to map out the region’s Groot Winterhoek Aquifer.

In 2012, the Coegakop area, inland from the Coega harbour and Industrial Development Zone, was identified as a potential high-yield zone. The ensuing drilling programme between February 2014 and July 2015 confirmed this.

“The idea of developing a WTW at Coegakop began to germinate,” says Marius van Jaarsveld, technical director, Zutari. “We were subsequently appointed by NMBM for the overall design, project and construction management. Construction of the Coegakop WTW commenced in March 2020.”

Prior to that, there was a long hiatus after the completion of the initial exploration drilling programme in 2015. Then, in April 2018, the next stage commenced with the establishment of the five production boreholes that will feed the future WTW, as well as the construction of their interconnecting raw water pipelines. The final processed water pipeline was also installed and connected to the existing Coegakop reservoir, with all these works completed in September 2019.

Coegakop WTW “The Nooitgedagt and Coegakop projects both have a key feature in common. Significantly, neither rely on local rainfall for their storage requirements and process outputs,” Verseput continues. “This was an essential stipulation for the city’s emergency water master plans.”

The Coegakop wellfield draws water from sources that have built up over tens of thousands of years. As part of the natural process, and if left unchecked, this groundwater progressively makes its way through a myriad of rock fissures – geological fault lines less than a centimetre thick – until it reaches the ocean at Algoa Bay. At present, Uitenhage taps into this water, which naturally flows to the surface at a local artesian spring. Around 6 Mℓ is processed daily to meet part of the town’s potable requirements. Based on the groundwater data collected at Coegakop, the peak output capacity for the new WTW has been determined at 20 Mℓ/day. ‘At this point we’re aiming for 17 Mℓ/day,” says Verseput, which ties into the DWS water use licence abstraction figure of 26 Mℓ/day.

A major portion of the funding for the final WTW phase, which amounts to some R212 million, is being provided by National Treasury through Cogta as Municipal Disaster Recovery Grant funding. The Stefanutti Stocks PCI Consortium has been appointed as the main contractor. The contract has an

intensive construction programme schedule running over a 25-month timeframe, or the equivalent of some 730 days. Stefanutti Stocks mobilised on-site on 5 June 2020.

“PCI Africa will be responsible for the mechanical, electrical, control and instrumentation component, with Stefanutti Stocks responsible for the construction of the integrated process control and administration building, as well as all related concrete structures.

Externally, that includes the construction of the settling ponds,” explains John Woodburn, contracts director, Stefanutti Stocks Coastal.

Provision has been made for the appointment of 100 emerging micro enterprises. In addition, employment opportunities will be created for local unskilled and semi-skilled labour drawn from the nearby Motherwell community.

Biofiltration needed The groundwater sourced from the wellfield contains high concentrations of dissolved iron (>7.5 mg/ℓ) and manganese (>2.5 mg/ℓ), which rules out the use of conventional chemical water purification, as is the case for Nooitgedagt. In the case of the Coegakop

A successful water strike: water rises to the surface under its own pressure

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NELSON MANDELA BAY & BUFFALO CITY 1

2

3

1E stablishing one of the production boreholes at Coegakop 2N ooitgedagt/Coega Low Level Scheme: Phase 3 3 Nooitgedagt expansion: the new settling tanks with sludge hoppers and flocculation channel

WTW, proprietary biofiltration technologies will be employed.

Zutari’s team is responsible for the process design and this will become the second of its kind built in South Africa. The first is a 10 Mℓ biofiltration plant in Hermanus, Western Cape, which was also designed by Zutari.

The upside is that the biological process costs will be cheaper. The cost per kilolitre of water will also be a lot less since it’s being sourced straight out of the ground. Aside from the iron and manganese elements, the water is pristine and characterised by low levels of salinity.

Coegakop’s production boreholes, which were completed during a previous phase, telescope down to an internal diameter of 300 mm and feature lined stainless-steel casings. Drilled to a depth of between 200 m and 300 m, the water abstraction rate is regulated by purposedesigned stainless-steel pumps. Being artesian systems, the water naturally travels up the borehole at a pressure of 6 bar and over, so the energy needs to be contained.

Aside from water purification, there are no additional bulk transfer costs since the treated water goes straight to the existing Coegakop reservoir approximately 650 m away. From there, pipelines supply Motherwell, the Coega IDZ and an expanding consumer zone.

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Integrated process building design Since the operators at Coegakop will be stationed there on a constant 24/7 basis, the WTW was designed to ensure maximum security for the occupants. To achieve this, the process and administration components are housed in one secure, self-contained building. A rainwater harvesting system has also been included in the design, which will flush the ablutions.

“The process and administration building forms the largest component and will entail intricate work, especially when installing the filtration systems,” says Andre van der Merwe, project manager, Stefanutti Stocks.

The borehole chamber buildings feature an innovative modular design. A section of the wall and roof will be constructed using removable precast panels. This will enable a drilling rig to be moved into position to work on the borehole, when required. Thereafter, everything can be closed up again. The balance of the chamber building is reinforced concrete.

The WTW design makes provision for extensions to the filtration works on either side of the filter banks. Thanks to the modular layout, units can be added either side of the treatment plant.

10 design workshops have been held jointly by Zutari, NMBM, and the Stefanutti Stocks PCI Consortium. To perfect the models, Zutari’s use of virtual (VR) and augmented reality (AR) software proved invaluable during the simulation and interrogation of the plant setup. This was the core of a technical paper that was presented at the 2018 IMESA Conference held in Port Elizabeth. Zutari also plans to use AR and VR to train the operators ahead of the plant’s opening, so that they can hit the ground running.

The numbers still need to be verified. However, once the plant is fully operational, NMBM is confident that Coegakop will supply the lowest cost per kilolitre of water within the NMBM water supply system - far lower, for example, than going the desalination route.

The exploration borehole network drilled to date extends north all the way from Coegakop to just past Uitenhage. Here, intermittent monitoring sites have been established. Some of the exploration boreholes at Coegakop will also be equipped with level sensors linked to a Scada system. Overall, this will determine how abstraction rates affect the overall aquifer. The data will also prove invaluable for the DWS in monitoring water use in terms of the licensed aquifer abstraction.

In the meantime, the project team is forging ahead to meet the Coegakop WTW’s targeted completion date in August 2022.

A design partnership from day one To bring the Coegakop project to this point,

www.stefanuttistocks.com

NELSON MANDELA BAY & BUFFALO CITY

The Proteus is the first instrument globally that has the potential to measure bacteria/coliforms in drinking water in real time

Monitoring, maintaining, and managing water and wastewater process engineering outputs requires the best technologies.

Downstream quality can never be compromised, says Jaco Haasbroek from Water Control Solutions Africa (WCS-Africa), which supplies and supports leading OEM solutions. Drought mitigation is an equally important factor.

W

ithin the water and wastewater spectrum, maintaining ser vices to households and industry is an absolute priority. In turn, water utilities make major infrastructure investments and municipalities are responsible for the final delivery.

Along the way, eroding factors include nonrevenue water losses, and unnecessarily high wastewater treatment costs. An example would be where aerators continue to run at full speed even though organic loads fluctuate during the day. Here, variable-speed drives can pass on energy savings during lower incoming BOD/COD conditions.

Other factors to consider include excessive chlorination dosing for potable water purification, and the lack of effective instrumentation to monitor and model current and future outcomes.

“Metering, monitoring and pressure management are standard operating practices for any new or existing system, but that’s interdependent on having the right tools in place,” says Haasbroek. “At WCS-Africa, we’ve brought together a suite of technologies that significantly improve efficiencies.”

Integrated technologies include: •water balance optimisation •non-revenue water mitigation •water scheme automation •telemetry management •leak detection •pressure management •asset condition assessment

•asset management •shared water savings •prepaid water metering.

Groundwater and reuse Process optimisation goes hand in hand with water conservation, especially in water-scarce regions affected by extended droughts. WCSAfrica works with consulting firms that specialise in groundwater exploration, borehole drilling, and the treatment of the abstracted water.

Water reuse is another important area.

Here, WCS-Africa provides solutions for service providers that include effluent quality testing, treatment design, grey- and blackwater separation, package plants and water storage.

SupplyFix provides an immediate and permanent solution for pipeline leaks

ACHIEVING WATER SECURITY THROUGH 4IR Proteus water quality sensor Included in WCS-Africa’s technology suite is the Proteus Instruments range. When it comes to water quality meters, Proteus sets the benchmark.

Proteus fields a multiparameter, real-time sensor platform to accurately and reliably measure BOD, COD, TOC and coliforms in permanent and temporary applications. Additional sensors can be added to measure parameters such as free chlorine, pH, redox, electrical conductivity, dissolved oxygen, and turbidity. The Proteus is designed to communicate with telemetry/Scada systems and other datalogging devices, like tablets and smartphones.

“These sensor probes are light and easy to use, plus they’re built to withstand the toughest field conditions,” says Haasbroek.

SupplyFix pipeline repairs Another innovative OEM solution is SupplyFix, which specialises in permanent water and sanitation pipeline repair interventions under live load conditions. Fittings can be used on straight pipe sections, 90-degree bends, T-pieces and joints. Benefits include zero downtime, plus no water or pressure losses (under most circumstances). Installation is also straightforward, with no cutting or augmentation required.

BestFix is a medium-pressure leak solution for pipelines operating at up to 16 bar and is suitable for most pipe materials, such as HDPE, AC, GRP, PVC and steel – and for diameters ranging from 12 mm to 2 000 mm.

Systems are available in lengths from 200 mm up to 1 000 mm.

AgriFix is a low-pressure leak solution for pipelines operating up to 9 bar and is the more economical option when compared to the medium-pressure BestFix range.

“Our holistic implementation of 4IR technologies ensures that every facet of the water and wastewater cycle is covered,” Haasbroek concludes.

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A HOLISTIC APPROACH TO WATER AND WASTEWATER PROCESS CONTROL WCS-Africa is a visionar y engineering group harnessing the best 4IR technologies from around the world.

Our OEM solutions bridge the infrastructure gap and ensure longer-term water security.

We par tner with industr y leaders to deliver groundwater and drought mitigation strategies.

Design and commissioning ser vices ensure optimum plant set-up and operation.

At WCS-Africa, we never crack under pressure.

Water Balance Non Revenue Water Mitigation Water Scheme Automation Telemetry Management Leak Detection Pressure Management

www.wcs-africa.com Asset Condition Assessment Asset Management Shared Water Savings Prepaid Water Metering

DISTRIBUTING AGENTS 50

IMIESA August 2020

MAN AG IN G

SOURCE M O TO FR R E TA T A P W

FOR MORE INFORMATION 062 521 8087

info@wcs-africa.com

www.lukhozi.co.za E-mail: info@lukhozi.co.za Level 2 B-BBEE contributor

Engineering through technology Lukhozi’s rich experience and diversity provides a unique perspective on how construction projects are designed and executed in the public and private sector.

We are committed to providing value engineering services that directly and indirectly contribute to positive and lasting change within communities and regional economies.

Share our vision for excellence.

Core services

EAST LONDON (HEAD OFFICE) +27 (0)43 721 1321 el@lukhozi.co.za

Agricultural engineering Building & Structures Environmental Management Transportation, Roads & Stormwater Management Health Care Facilities Management Housing Property Development Project Management Water and Sanitation

CAPE TOWN +27 (0)21 686 2550 ct@lukhozi.co.za

PORT ELIZABETH +27 (0)41 363 1984 pe@lukhozi.co.za

QUEENSTOWN +27 (0)45 839 2532 qt@lukhozi.co.za

JOHANNESBURG +27 (0)11 064 1639 jhb@lukhozi.co.za

NELSON MANDELA BAY & BUFFALO CITY

Celebrating its 20th anniversar y in 2020, Lukhozi Consulting Engineers is a multidisciplinar y consulting firm rolling out projects nationally from its home base in the Eastern Cape.

Greg Tucker, managing director, Lukhozi, outlines the company’s operating philosophy, which spans the private and public sector.

Niche infrastructure delivery

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ukhozi’s two decades of project excellence have been founded on a commitment to ethical design and execution according to worldclass engineering and quality standards. The company is ISO 9001 certified and a Level 2 BBBEE contributor.

“From inception, we’ve always embraced innovation, which includes keeping up to date with the latest information technology and engineering software,” says Tucker. “That certainly paid off when the hard lockdown hit, because our cloud-based platforms facilitate remote working. Our digital transformation has enabled us to improve communications and time and cost efficiencies in design teams and project management in these uncertain times. Technologies like augmented and virtual reality also allow our engineers and clients to experience walkthrough simulations, which we can then refine in practice on-site.”

Lukhozi’s expertise within the infrastructure space encompasses all engineering disciplines, project and construction

Nooiensfontein sewage pump station and rising main: the Western Cape Department of Human Settlements appointed Lukhozi for the design and implementation of a R54 million sewage diversion contract. The work entailed civil, structural, electrical, mechanical engineering, environmental and project management services

The Ripplemead citrus pack house in Peddie, Eastern Cape, was designed and executed for the Department of Rural Development and Agrarian Reform

management, facilities management, and scientific and environmental services. Core areas include water and sanitation, roads and stormwater, and housing. Prevailing drought conditions, combined with the onset of Covid19, have made health services, as well as water and sanitation projects, urgent priorities.

Lukhozi has completed extensive work for the Eastern Cape Department of Health. Over the past three years, this has entailed upgrades and refurbishments at more than 100 medical facilities.

“Municipal engineering is an economic and social enabler; infrastructure sustains and grows economies. That’s vitally important in economically depressed regions like the Eastern Cape,” says Tucker.

ELIDZ manufacturing facilities: the East London IDZ appointed Lukhozi as project managers for four facilities. These comprise the HS1 facility (R89 million) and GE1 facility (R150 million), both scheduled to be completed by December 2020; extension to the Automould Factory (R40 million), where construction is to commence by November 2020; and the Bushveld Energy Processing Plant (R36 million), which is currently at design stage. Lukhozi is also appointed as the civil engineer and environmental control officer at the HW1 facility (R113 million), where construction is scheduled to be completed by December 2020

Value engineering Lukhozi’s success has been founded on finding solutions and adding value. This includes providing opportunities for emerging contractors by designing projects in such a way that they can be divided into smaller, labourintensive work packages. EME facilitation and community engagement are vital for successful project implementation.

Current projects Within the Nelson Mandela Bay region, major work includes a gravel-to-surfaced-road programme and municipal services for the Kwanobuhle housing project, comprising some 3 000 units.

In the East London area, five projects are under way in the East London IDZ, along with various municipal services projects for Buffalo

City metro, and several housing projects in and around East London.

Beyond the Eastern Cape, current projects include building projects in Gauteng and the provision of bulk and internal water, sanitation, roads and stormwater services, and top structures for Forest Village – a major residential development in Blue Downs, Cape Town, comprising some 4 500 housing units – among others.

“Our strategic vision is to continue the digital transformation of our operations to keep pace with ever-changing technology, which for us defines the Fourth Industrial Revolution and artificial intelligence. We aim to do this without losing the personal touch that has made us accessible and relevant over the past 20 years,” Tucker concludes.

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www.kcs.co.za

KCS Consultants (Pty) Ltd is a civil engineering firm specialising in the design and construction supervision of civil infrastructure with a focus on sewer, roads, stormwater, water infrastructure and project management.

The new bridge over the Sidubu River completed in 2018

Some of our engineering and project management projects include the following: • Upgrading of Provincial Road DR08376 from the R61 at St Marks to Sabalele Village (Chris Hani’s Birthplace) in the Chris Hani Region of the Eastern Cape (R200 million) • Manufacturing facilities in the East London IDZ, Eastern Cape (R180 million and R360 million) – completed in 2020

Manufacturing facilities in the East London IDZ

The Civil Suite Engineering Design Software has been developed by KCS Consultants and the suite comprises the following modules:

TERRAIN

WATER

ROADS

SEWER STORMWATER PIPELINE

Actual screenshot of the training web site: courses.civilsuite.com

CAD/GIS

Developed in South Africa and built around an engine capable of reading and writing DWG/DXF drawings natively providing the professional engineer with an integrated suite of programs from initial designs through to the final plotted drawings.

For more information, please visit www.civilsuite.com

P.O. Box 40332 | Walmer | Port Elizabeth | 6065

+27 (0)41 373 6729

sales@civilsuite.com

NELSON MANDELA BAY & BUFFALO CITY KCS Consultants is a civil engineering firm specialising in project and asset management, civil and structural engineering, as well as allied engineering software development and support. It offers a wide range of solutions to problems that rural and urban communities encounter.

Furthermore, the suite includes a sewer model

CIVIL SUITE SOFTWARE

A

t KCS Consultants, we strive to have excellence and ingenuity built into every design. It is our passion to create innovative, efficient and economical engineering solutions of the highest quality that exceed the expectations of our clients.

Our staff are able to meet a diverse range of client needs by gaining skills and insight from Southern, Eastern and Western Africa, as well as the Middle East. Our team has overall expertise in civil and structural projects such as transportation and roads, stormwater management, urban and regional rural water and sanitation schemes, housing, sectional title, agricultural developments, IDZ establishment, and asset and project management.

We are also the developers of the Civil Suite Engineering Design software, which includes modules for CAD, GIS, terrain modelling, sewer, road, stormwater, water and pipeline designs.

Civil Suite Engineering Design Suite The Civil Suite started development in 1996 and is the brainchild of the director of KCS Consultants, Keith Simon, PrEng PrCPM. At the time, Keith noted a lack of suitable civil engineering design and training software. Thus, the idea of creating a user-friendly design software package that would meet the needs of the civil engineer was born. He created a state-of-the-art software package with a common interface that provides users with the functionality to undertake their terrain modelling, road, sewer, stormwater and water network designs in a CADbased environment.

The integrated interface not only allows the designer to work with their DWG/DXF drawings natively (without the need for a separate CAD license), but also includes a terrain model capable of handling up to 22 million points at unbelievable speeds.

that effectively does around 99% of the work automatically, and competent road, water (based on US EPANet engine) and stormwater (based on EPASWMM) design modules too.

Our software tools are widely used by various consultants to assist with the planning, design and management of municipal infrastructure, underlying the usefulness of the software and its functionality. The software is constantly being updated and currently allows the user to complete 100% of the CAD functionality including dimensions, hatching, etc.

Civil Suite Online Courses KCS Consultants usually runs two two-day courses per year hosting users at its offices in Port Elizabeth. In November 2019, we started developing online courses to assist users by reducing their travel and accommodation costs when attending our courses.

As the Covid-19 pandemic reached our shores, we recognised that the demand for online learning would be heightened even further.

Thus, in keeping up with the challenges of an ever-changing world, KCS Consultants created a series of online tutorials that speaks to the seasoned engineer, as well as the fresh civil engineering or technical graduate.

These tutorials are hosted on the website and the KCS team is currently finalising submissions for CPD certifications of the courses for the following modules: • Terrain • CAD/GIS

• Sewer • Water • Roads.

The Stormwater and Pipeline modules will follow next.

Software for Civil Suite Online Courses As part of our Civil Suite offering, we will be making available a fully functional version free for use as part of the coursework.

This version has a limited time period during which the courses should be completed.

Under no circumstances will we extend the runtime period.

All the online courses are fully documented using instructional videos and tutorials. We believe our product presents excellent value and we will discount the product to those users interested in purchasing the software on completion of the courses. These instructional videos are hosted on YouTube; however, the courses are hosted in-house at our data centre, which is connected to the internet by 200 Mbps fibre-optic lines, so uptime and performance are always guaranteed.

The software has to be authorised online and the courses themselves require an internet connection. Users can undertake the training in the convenience of their own time and space.

We believe that once we obtain CPD certification for the various courses, we would be in a unique position to offer excellent training opportunities very competitively; however, we will note that it could take a considerable amount of time to complete all the various modules due to the complex nature of the content.

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NELSON MANDELA BAY & BUFFALO CITY Construction under way on the Qumza Highway upgrade

Roads to economic The completed upgrade and the Qumza Highway

Improving road infrastructure remains a key priority across the Buffalo City Metropolitan Municipality. Two multimillionrand projects, with a focus on road expansion, are currently under way and expected to unlock the city’s economy.

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uffalo City’s focus on roads is underpinned by the belief that improved road infrastructure will help stimulate the metro’s economy. The city’s flagship Sleeper Site Project as well as the Qumza Highway Project are expected to do just that.

Sleeper Site Project The multimillion-rand Sleeper Site Project will see the development of a 13 ha pocket of land that has been vacant for years.

This prime inner-city land, previously owned

by Transnet and bound by the central railway station, has been earmarked for development that will include the construction of a new civic centre, new council chambers, shopping malls, accommodation and office parks. Once complete, it is expected to be transformed into a bright new stronghold for government, academia and business that will revitalise the metro.

The phased project is funded by the Urban Settlement Development Grant (USDG). Phase 1 involves the realignment of the R72 from

growth

Tutton Terrance through Sleeper Bush, joining Fitzpatrick Road up to the Bowls Road Buffalo Park intersection. This includes the greenfield construction of a new section of road, as well as the rehabilitation of a section of existing road from Panmure Place to the Bowls Road Buffalo Park intersection.

Intended to alleviate traffic congestion in the CBD, the 16-month, R60 million project is earmarked for completion in March 2021.

Following this, Phase 2 will involve the upgrading of Currie Street from Tutton to the Fleet Street Intersection.

“The new road will provide direct linkage between the N2 and R72 without going through the CBD. Traffic will be able to get to the airport quicker as the realignment will reduce the travel time. It will also open up access to the land for broader development within the Sleeper Site area,” says Ayanda Skwebu, programme manager, Buffalo City Metropolitan Municipality.

He explains that the road will alleviate traffic on the eastern side of Quigney and will include street lighting, pedestrian walkways and a central island for pedestrian refuge. Pedestrian ramps will also be installed to cater for the physically impaired. Six SMME contractors have been employed on the project to date.

Qumza Highway The Buffalo City Spatial Planning Department launched the upgrade of Qumza Highway Phase 7 Project on 13 July 2017.

The 30-month, R285 million contract involved the rehabilitation and widening of the Qumza Highway on both sides to a dual carriageway.

PROJECT TEAM: QUMZA HIGHWAY Client: Buffalo City Metropolitan Municipality Engineer: Element Consulting Engineers Contractor: Down Touch Investments

The entire Qumza Highway Phase 7 earmarked for upgrade is 4.21 km, starting at the Mdantsane Nu6 Mall main entrance to the Sasol Fort Jackson garage. The current contract, Phase 7-2 has a total length of 2.83 km from Mazidlekhaya intersection (Nu12) to Mdantsane Mall (Nu6).

A major driver behind the upgrade is increased safety for road users. The narrowness of the road has in the past resulted a high volume of head-on collisions and vehiclepedestrian conflict.

According to Skwebu, the central island will reduce head-on collisions on the road, which is a major linkage from Mdantsane and mainly used by public transport. Speed humps are included along the route to reduce speeds and pedestrian crossings are demarcated.

New traffic circles will ensure safe access for vehicles joining the road from side streets.

The upgrade is also expected to alleviate traffic congestion and reduce travelling time within Mdantsane.

Over the course of the project, 24 SMMEs were appointed.

PROJECT TEAM: SLEEPER SITE Client: Buffalo City Metropolitan Municipality Engineer: Element Consulting Engineers Contractor: Down Touch Investments

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Work under way on Sleeper Site Phase 1

NELSON MANDELA BAY & BUFFALO CITY Until June 2019, residents of Needs Camp (Phumalani) and Potsdam, separated by the Buffalo River, were forced to cross a weir at the Bridle Drift Dam to reach each other, often resulting in drownings.

T

o address the problem, Buffalo City Metropolitan Municipality appointed Aurecon (now Zutari) to provide professional engineering services for the planning, design and implementation of a new bridge over the Buffalo River to connect Needs Camp Village with Potsdam Village.

The goal was to make it easy for people to walk from one village to the other and allow people and vehicles to drive from the R346 to the N2 and R102.

Bridging communities

Addressing community needs The needs of the community were a key driver in this project. The community members of Needs Camp had called for better access to employment, schools, businesses and social services in Mdantsane via Potsdam Village. The bridge has eliminated the risk of drowning while crossing the river and now provides community members with better access to these opportunities, enhanced by taxi services between Needs Camp and Mdantsane CBD. Job creation was an important goal and, where possible, labour-intensive construction techniques were used. Due to the size of the project, mass earthworks and layerworks were done conventionally with machines, but pipe culverts, line side drains, drainage berms, gabions, subsurface drainage and block paving were chosen to maximise labourintensive construction activities.

The project team tried to split the labour employment 50/50 between Needs Camp and Potsdam Village, and community members received training on paving, reinforcement and concrete – skills that they can use for future employment opportunities.

Innovative solutions Buffalo City Metropolitan Municipality believes that the project was ingenious in how it implemented a road that would save the municipality both in terms of cost and maintenance over the road’s life cycle.

Two pavement alternatives – paving block and asphalt – were considered. The paving block option was cheaper due to the G2 base

pavement layer that would be required for an asphalt road, offering a more cost-effective life cycle over a 25-year period.

Paving proved to be the most labourintensive construction method, ensuring more jobs and skills transfer to the maximum number of community members. It is also believed that block paving assists in calming traffic speeds, as the rougher road surface causes more noise and vibration in the vehicle at higher speeds.

The drawback of this method is the paving’s ability to accumulate rainwater and damage the road. To ensure that rainwater is redirected away from the road as quickly as possible, the team allowed for a 4% cross fall around corners and a 3% cross fall on flat areas.

To ensure that the flow of traffic is smooth and safe, mountable kerbs were designed.

These mountable kerbs enable taxis to move partially off the carriageway when dropping off and picking up passengers. This limits disruptions to traffic and enhances commuter safety.

The project also reduces the amount of maintenance the municipality needs to perform. Instead of implementing dropin stormwater inlet manholes, which are usually found within municipal areas, the project team opted for open straight headwall drainage structures.

This decision avoids manholes being filled with silt, which can accumulate and create additional maintenance work. The open straight headwall culverts help the system to be self-flushing and reduce the accumulation of silt, allowing the water to pass through instead of dropping into a manhole, which will protect the integrity of the road.

The project team ensured that the R90 million project was delivered effectively, meeting the needs of both the client and the community.

IMIESA August 2020

57

Power for the people It is our mission to uplift, develop and empower local communities, businesses and other organisations.

From conception to implementation and beyond: we cover every facet of the electrical engineering value chain to deliver sustained energy demand.

30

WORKED FOR MORE THAN

M U N I C I PA L I T I E S NUMBER OF PROJECTS C O M P L E T E D

552 20 1000 11

Turnkey solutions • Renewable energy • Power system consulting • Field services • Testing and commissioning

Your Partner in Power

BBBEE Level 2 contributor

Custom-built switchgear and control panels Sales, design, engineering, assembly and turnkey solutions for: • MV switchgear • LV switchgear • Substation control plant panels

EAST LONDON 043 726 2726 info.el@eya-bantu.co.za

CAPE TOWN 021 975 2999 info.ct@eya-bantu.co.za

WORKED ON MORE THAN

WIND FARMS & SOLAR FARMS MORE THAN

COMBINED YEARS EXPERIENCE IN ENGINEERING

COUNTRIES WORKED IN

Tanzania, Mozambique, Lesotho, Malawi, Zambia, Botswana, Namibia, Eritrea, Zimbabwe, Swaziland and South Africa

PORT ELIZABETH 041 368 3224 info.pe@eya-bantu.co.za GEORGE 044 871 5286 info.g@eya-bantu.co.za

BLOEMFONTEIN 079 885 9744 info.bloem@eya-bantu.co.za ZAMBIA 0027437262726 0027823763206 | 0027823712963 info.int@eya-bantu.co.za

www.eyabantu.com

NELSON MANDELA BAY & BUFFALO CITY

Established in 1999, Eya Bantu is a specialist consulting engineering firm providing turnkey solutions for high-, mediumand low-voltage (HV, MV and LV) segments. More recently, this has included diversification into the renewable energy sector, as well as the expansion of its switchgear and control panel assembly plant in Port Elizabeth.

Power by design

F

or close on a decade, South Africa has experienced an increasingly unstable national grid, exacerbated by delays in completing key coal-fired power station projects. The overall energy security situation has been further compounded by the fact that many municipalities have ageing infrastructure, which needs replacing.

Municipalities also need to plan and make provision for current and future electrification roll-outs, ranging from human settlements to Industrial Development Zones. Since 1999, Eya Bantu has worked with more than 30 municipalities across South Africa to meet and sustain their power requirements.

“The effective management, upgrading and maintenance of electrical infrastructure is crucial for every aspect of South Africa’s economy and its communities,” explains Mike Brown, director, Eya Bantu, a BBBEE Level 2 contributor. “Our expertise and services are part of the solution.”

In addition to design and project management, Eya Bantu’s key services include power systems consulting and feasibility studies, helping clients decide on the optimum energy platforms, ranging from cogeneration to biogas and self-contained microgrids.

Once designed, Eya Bantu follows through with installation supervision, field services, testing and commissioning. Other services include cable fault finding as well as LV, MV and HV electrical maintenance.

“Going forward, we’re seeing an exciting evolution in the energy mix, with solar and wind farms becoming far more common,” he continues.

Fabrication arm The Port Elizabeth assembly factory has undergone continued expansion in the past two years. The two main product lines are MV switchgear and substation control panels, assembled using minimal imported OEM components and increasing the local content of the product. OEMs include Schneider Electricand ABB for MV switchgear; and Schneider, ABB, Schweitzer and Eaton for LV systems. Eya Bantu also has agency agreements in place for protection relays, automation equipment, Scada, RTU and UPS products.

The company recently concluded a licensing agreement with Schneider to assemble its air insulated PIX Easy MV switchgear line, designed for ratings up to 17.5 kV. Providing safe, reliable and simplified operation, applications include electrical utilities, renewable energy IPPs, buildings, the manufacturing sector, municipalities, and water and wastewater plants.

“In addition to the high local content component, our in-depth design experience and commissioning expertise enable us to develop custom solutions within quick

A technician configuring a control panel

Assembly in process on MV switchgear units

turnaround times,” explains Jadri Hurter, director: Business Development at Eya Bantu.

All products incorporate state-of-the-art technologies, are backed by OEM warranties, and come to market at competitive prices, with backup support provided right at the client’s doorstep.

The control panel line, extending up to 765 kV, continues to grow from strength to strength, meeting demand across a diverse client base that includes parastatals, municipalities, general industry and the renewable energy market.

Cross-border market The surge in renewable power led to Eya Bantu opening a branch in Bloemfontein to service large-scale solar PV installations, particularly in the Northern Cape. So far, the company’s services have contributed to adding more than 1 000 MVA of clean power to the grid.

“From inception, Eya Bantu has worked selectively across Africa, where we currently provide turnkey services for countries that include Botswana, Lesotho, Mozambique, Tanzania, Zambia and Zimbabwe. In September 2019, we opened a permanent office in Kitwe, Zambia, to support the mining and energy sectors there, as well as other regional markets on the continent,” says Brown.

“Both at home and abroad, our niche electrical engineering focus ensures that our public and private sector clients have the best power solutions,” he concludes.

IMIESA August 2020

59

WASTE MANAGEMENT

How to extend the life of your landfill A lack of commercially viable alternatives means that landfilling remains the only option for the safe and costeffective disposal of waste. However, there is a dire shor tage of airspace on existing landfill sites.

By Danielle Petterson

G

auteng presents a prime example of the airspace crisis facing South Africa.

Johannesburg, in particular, has an estimated remaining life of less than five years for all four of its landfills. While less severe, Tshwane and Ekurhuleni are facing similar situations; however, the problem persists across the country. It therefore stands that the lifespans of landfills need to be extended wherever possible.

According to Stan Jewaskiewitz, technical director, Envitech Solutions, there has generally been little forward planning for future waste disposal in South Africa. Added to that, many of the provincial environmental authorities

are refusing to issue new landfill licences without planning in place for alternatives, such as recycling.

Jewaskiewitz also points out that some landfills are known to be at full capacity and yet continue to operate, which implies non-compliance with their waste management licence. Various options therefore need to be considered in order to prolong landfill lifespans.

In this regard, there are three basic options available: • physical extension of landfills • diversion of waste from landfill • waste processing and treatment at landfill.

General Waste (MSW/ Industrial/ Commercial)

Waste Reception (Bulk Sorting)

Recovered materials for reprocessing (plastics, glass, cans, paper, etc) Organics Organics

Anaerobic Digestion / Composting Plant (Option)

Dry waste Biogas Residue to Landfill

Medical Waste (HCRW)

Infectious

Hydroclave Plant (Infectious Wastes)

Pathalogical

Nonagricultural grade compost Thermal Treatment Plant

Shredded Tyres (Option)

Residue Organic sludge

Hazardous Wastes

60

IMIESA August 2020

Laboratory (Check Testing)

Chemical Treatment Plant

Where conditions allow, landfills can be extended laterally or vertically to increase lifespan. These options come with various engineering considerations in terms of stability and require an appropriate licence to perform. Concerns from the community and the impact on community aesthetics must be taken into consideration.

According to Jewaskiewitz, this is one of the easiest ways to extend the life of a landfill, and the advantage of this option is that the operations are unsophisticated in comparison to the alternatives. On the downside, in cases where landfills are run by incompetent operators or municipalities, poor practices will be perpetuated.

Diversion of waste from landfill

This approach relies on off-site activities to divert waste before it reaches the landfill. In doing so, the volume of waste to landfill is decreased, thereby increasing the lifespan of the landfill. Diversion activities include recycling, composting organic waste, and crushing rubble for reuse, among others.

Adopting these activities offers Recyclables advantages to the recycling and composting markets, and generates employment Compost opportunities. Recycling, for (Option) example, currently takes place largely through informal waste Electricity collectors. This approach also Generation requires relatively low-level technology and is suitable for Steam/ Syngas all municipalities.

However, political will is key to facilitate effective diversion Ash activities, says Jewaskiewitz.

Landfill This is because they are not (Residue Disposal) easy to establish, and viable markets or uses for the by-products must be established – e.g. collaborating with parks

Integrated Waste Treatment & Disposal Solution Recycling Facility (MRF)

Physical extension of landfills

WASTE MANAGEMENT

departments to use the compost generated from organic waste. Buy-in from residents is also crucial to ensure effective waste separation at source, which is by far the most effective method of separation.

Waste processing and treatment at landfill Similar to diversion, this approach involves sorting waste at the landfill site, to ensure only materials that cannot be processed are disposed of on the landfill. “This acts as a back-stop to all of the activities that happen prior to the waste reaching the landfill,” says Jewaskiewitz.

Using this approach, waste would be processed on-site, typically at a materials recovery facility, where recoverable materials, such as recyclables and organics, are separated out. Like diversion, this approach offers benefits to the recycling and composting markets and creates jobs and upskilling opportunities.

Waste-to-energy also falls into this category.

The residual material that would normally go to

landfill can be incinerated to generate steam and electricity. Electricity can be used on-site or fed into the grid, and nearby industries that require steam in their processes, such as the pulp and paper industry, can use the steam by-product in their processes.

Unfortunately, the difficulties involved in setting up waste-to-energy projects, such as high costs and securing sustained volumes of quality waste, mean there are few to no commercial-scale plants in South Africa.

However, the use of waste materials to produce refuse-derived fuels for certain industries has been successfully implemented in some areas.

Jewaskiewitz notes that this approach is generally not suitable for small municipalities, as these projects are capital-intensive and typically require skilled staff that are often not available. “Most importantly, for this approach to be successful, you need politicians to champion and support these projects,” he adds.

An integrated solution “What do you do with the waste when landfills

Long environmental approval processes, vast amounts of red tape, and inconsistent enforcement of regulations are major stumbling blocks that deter investors.” are full?” questions Jewaskiewitz. “This is why we need to consider an integrated waste treatment and disposal solution where the individual components form the building blocks of the overall solution.”

However, he stresses that there are many challenges to overcome. Long environmental approval processes, vast amounts of red tape, and inconsistent enforcement of regulations are major stumbling blocks that deter investors.

“We need to take our National Waste Management Strategy, look at what we’ve achieved over the last 10 years, and take an informed approach moving forward,” he concludes.

Specialist Waste Management Consultants • • • • • •

Waste Collection Optimisation Waste Transfer Station design General Waste Landfill design Hazardous Waste Landfill design Landfill Rehabilitation Landfill Auditing and Monitoring

Contact Numbers

Telephone:+27 (0)21 982 6570 Fax:+27 (0)21 981 0868

• • • • • •

Landfill Closure Leachate Treatment Regional Waste Studies PPP Involvement in Waste Management Alternative Technologies for Waste Reduction Integrated Waste Management Plans

Physical Address

60 Bracken Street, Protea Heights South Africa, 7560

www.jpce.co.za

Postal Address

P.O. Box 931, Brackenfell South Africa, 7561

LEGAL

PPPs

– the benefits and obstacles to success It is no secret that South Africa has many infrastructure needs. Several projects across the energy, water and transport infrastructure sectors could create improved conditions and provide much-needed work in the declining construction sector. By Natalie Reyneke*

C

ovid-19 has struck a severe blow to an already ailing construction sector, as well as to the prioritisation of public spending in the face of pressing delivery of healthcare and other needs of citizens. In this difficult time, partnerships between the private and public sectors are vital.

A build, own, operate and transfer (BOOT) agreement is a contracting strategy often applied to large infrastructure projects.

It is used when a private organisation implements a large project, and the appointed contractor builds and operates the project for the client for a period after completion of the build. The assets are then handed back to the client. In South Africa’s public sector, the mechanism for this contracting strategy is a publicprivate partnership (PPP).

PPPs have been successfully used in South Africa since 1998 and some of

Natalie Reyneke, director, MDA Attorneys

62

IMIESA August 2020

the country’s most well-known projects were developed under PPP contracts.

Given the substantial benefits of this strategy, a specialist unit was created at National Treasury and there is much information available to encourage PPPs as a way to ensure service delivery at value-for-money costs and with greater certainty of the required quality and service delivery standards.

PPPs versus other procurement strategies A PPP, as the name implies, is a longterm contract between the public and private sector to ensure the delivery of well-maintained, cost-effective public infrastructure or services, by leveraging private sector expertise and transferring risk to the private sector.

When public services or infrastructure are procured in the conventional system, government pays for capital and operating costs and carries the risks associated with cost overruns and late delivery.

While the expertise and experience of a private company may be procured for the design and construction of infrastructure, the private company is paid once the asset is delivered and the interaction ends there. The public sector is then responsible for the staffing, maintenance and operation of the asset.

There are several benefits of PPP procurement: • PPPs leverage private party capital to fund infrastructure and provide budgetary certainty.

• PPPs leverage private sector skills and only require payment when services are delivered.

• PPPs can be good for project planning and quality assurance.

• Risks are allocated to the party best able to manage a particular risk.

Some PPPs, where fees are generated on a user-pay basis, derive income from which government departments or municipalities can share benefits.

PPPs are also a good vehicle for other social objectives, such as economic empowerment, through aligning the incentives of the private party with those objectives.

The definition of a PPP in Treasury Regulation 16 specifies that a PPP is not a simple outsourcing of functions; rather it is a long-term contract involving substantial risk transfer. It is also not a donation by a private party for a public good, nor the privatisation of state assets and/or liabilities.

Legislation and support for PPPs The main legislation governing PPPs at the national and provincial levels of government is the Public Finance Management Act (No. 1 of 1999; PFMA) and Treasury Regulation 16. Municipal PPPs are governed under the Municipal Finance Management Act (No. 56 of 2003; MFMA) and its regulations, and the Municipal Systems Act (No. 44 of 2003).

All this legislation supports and reflects government’s policy objectives for delivering infrastructure and public services, in line with its constitutional mandate. As a means of procuring and delivering infrastructure services, PPPs are in line with the intent of both the PFMA and MFMA. Both acts focus on delivering outputs through value-formoney solutions.

The Government Technical Advisory Centre, or GTAC, is an agency of National

LEGAL

Treasury, established to support public finance management through professional advisory services, programme and project management, and transaction suppor t.

GTAC reports to the Minister of Finance and is established as a government component in terms of the Public Service Act (No. 103 of 1994).

The Transaction Advisory Service unit of GTAC provides specialised transaction advisory services with regard to PPPs. In specific instances, this support may include project implementation, monitoring and project implementation support.

GTAC assists departments and organs of state in establishing appropriate transactional advisor y support for both large projects and smaller transactions.

The agency has developed numerous methodologies, manuals and guidelines, which are available on its website to assist in achieving the best outcomes for PPPs.

The process of PPPs PPPs are complex contractual and operational arrangements. Since they involve several players from different sectors representing a variety of interests, the partnership needs to be formalised and processes need to be followed in a systematic and transparent way.

To ensure that these complexities are dealt with appropriately, detailed documentation needs to be prepared at all phases of a PPP

project. The PPP project cycle comprises four key decision points: • Inception – the procuring institution registers the project with National Treasury’s PPP Unit.

• Feasibility study – the procuring institution appoints private sector advisors to do a feasibility study on the most appropriate mechanism for procuring the project.

• Procurement – if the feasibility study shows that a PPP is a viable option, the procuring institution invites the market to submit bids for the infrastructure and/or service provision project.

• Implementation – the project is implemented once a suitable bidder has been chosen.

At all phases of a project’s development, the inputs of both the procuring institution and the private party need to be assessed in terms of their compliance with the legislation, the regulations, and the process and its components, including with the bidding process, the BBBEE component, and the formation of the special-purpose vehicle to house the project.

Standardised provisions are outlined in a guideline published specifically to address the key issues likely to arise in PPPs. It prescribes how these issues must be dealt with in a PPP agreement to achieve the requirements of substantial risk transfer, value for money and affordability, as defined or otherwise dealt with in Treasury Regulation 16.

Planning for a successful PPP At MDA Attorneys, we strongly advocate collaborative contracting in the belief that the best projects have little to do with trying to force all parties to adhere to strict contractual obligations. In PPP contracts, this is especially important. A focus on contract terms often sets up parties to act more like adversaries than allies. A productive working relationship over the life of the PPP project is more likely to be founded in a strong partnership approach beyond the terms of the contract, builtin mechanisms to share perspectives about the project (especially problems and concerns), and effective ways to rebound from failures to deliver.

Contracts spell out what must go right and what happens when things go wrong, but they cannot anticipate all possibilities and they do not provide any guidance on how to get back on track quickly. It boils down to the leaders from each party regularly sharing their interests and concerns, and a commitment to resolving them together.

In conclusion, PPPs have proved to be beneficial contracting arrangements in South Africa. Like all contracts, they must be clear and unambiguous, but the greatest factor for success in PPPs is a collaborative contracting approach. *Natalie Reyneke MDA Attorneys.

is

a

director

at

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ARRB Systems

8

IMESA

Bosch Munitech

2

InfraChamps Consulting

30

Rocla

23

JPCE

61

Sabita

11 46

Circuit Water Engineering

OBC

4, 64

Rand Water

31, 36

Coega Development Corporation

44

KCS Consulting

54

Stefanutti

Colas

17

Lukhozi Consulting Engineers

52

Vega Controls

Eya Bantu Professional Services

58

Maccaferri

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WCS-Africa

50

Wear Solutions Africa

16

Zutari

39

Franki IFC Gabion Baskets

25

M&D Construction Quality Filtration Systems

OFC 35

IBC

IMIESA August 2020

63

I M E S A A F F I L I AT E M E M B E R S

IMESA

PROFESSIONAL AFFILIATES ARRB Systems info@arrbsystemssa.com AECOM siphokuhle.dlamini@aecom.com AFI Consult banie@afri-infra.com Alake Consulting Engineers lunga@alakeconsulting.com ALULA (Pty) Ltd info@alulawater.co.za AQUADAM (Pty) Ltd sales@aquadam.co.za Asla Construction (Pty) Ltd johanv@asla.co.za 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 Dlamindlovu Consulting Engineers & Project Managers info@dlami-ndlovu.co.za DPI Plastics Farhana@dpiplastics.co.za EFG Engineers eric@efgeng.co.za Elster Kent Metering Mark.Shamley@Honeywell.com ERWAT mail@erwat.co.za GIBB marketing@gibb.co.za GIGSA secretary@gigsa.org GLS Consulting nicky@gls.co.za Gorman Rupp Cordeiro@gormanrupp.co.za Gudunkomo Investments & Consulting info@gudunkomo.co.za Hatch Africa (Pty) Ltd info@hatch.co.za Herrenknecht schiewe.helene@herrenknecht.de Huber Technology cs@hubersa.com Hydro-comp Enterprises info@edams.co.za I@Consulting info@iaconsulting.co.za Infrachamps Consulting info@infrachamps.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 ccherry@ctokamteys.co.za Kitso Botlhale Consulting Engineers info@kitsobce.co.za 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 Mariswe (Pty) Ltd neshniec@mariswe.com Martin & East gbyron@martin-east.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 Mvubu Consulting & Project Managers miranda@mvubu.net NAKO ILISO lyn.adams@nakogroup.com Nyeleti Consulting merasmus@nyeleti.co.za Odour Engineering Systems mathewc@oes.co.za Ribicon Consulting Group (Pty) Ltd info@ribicon.co.za Rainbow Reservoirs quin@rainbowres.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 Sobek Engineering gen@sobek.co.za Southern African Society for Trenchless Technology director@sasst.org.za spc@vinci-construction.com Southern Pipeline Contractors (Pty) Ltd 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 V3 Consulting Engineers (Pty) Ltd info@v3consulting.co.za Vetasi south-africa@vetasi.com VIP Consulting Engineers esme@vipconsulting.co.za VNA info@vnac.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 Zutari Rashree.Maharaj@Zutari.com

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