IMIESA September 2025

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

INFRASTRUCTURE DEVELOPMENT • SERVICE DELIVERY • ROADS • BUILDING • MAINTENANCE • ENERGY • WASTE

INDUSTRY INSIGHT Scott Magnus

Contract Manager at BLOC Contractors Isipingo’s dune tunnel provides stormwater relief

SOCIAL INFRASTRUCTURE

PIPE SYSTEMS

Primary school project showcases future-proof innovation

Classification – the heart of thermoplastic pipes

CEMENT & CONCRETE TECHNOLOGY Tests prove colloidal silica optimises durability

RAILWAY ENGINEERING Namibian line upgrade enhances SADC links

Gabion Baskets

The masters in erosion mitigation and river management

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A FIRST FOR AFRICA and a giant leap for infrastructure Sizabantu Piping Systems launches Africa’s first locally manufactured pipes, with capability from 710mm to 1200mm, now in full production

With capability from 710mm to 1200m now in production

INSIDE

VOLUME 50 NO. 08 SEPTEMBER 2025

26

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Regulars

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

INFRASTRUCTURE DEVELOPMENT • SERVICE DELIVERY • ROADS • BUILDING • MAINTENANCE • ENERGY • WASTE

INDUSTRY INSIGHT Scott Magnus

Contract Manager at BLOC Contractors

Railway Engineering

Editor’s comment

3

Shifting from road to rail. Walvis Bay to

President’s comment

4

Kranzberg line upgrade enhances

Index to advertisers

48

SADC links

32

Isipingo’s dune tunnel provides stormwater relief

SOCIAL INFRASTRUCTURE

PIPE SYSTEMS

Primary school project showcases future-proof innovation

Classification – the heart of thermoplastic pipes

CEMENT & CONCRETE TECHNOLOGY Tests prove colloidal silica optimises durability

RAILWAY ENGINEERING Namibian line upgrade enhances SADC links

Gabion Baskets

The masters in erosion mitigation and river management

Cover Story Gabions are the critical interface for river management

Renewable Energy & Electrification Protecting buildings’ embodied carbon 6

IMESA Smart infrastructure requires a collaborative response

10

As environmentally engineered structures, gabion systems have proven themselves worldwide as the preferred solution for riverine protection, embankment stabilisation and erosion mitigation. IMIESA speaks to Louis Cheyne, Managing Director of Gabion Baskets, about the key advantages, citing recent case studies that showcase innovation. P6

INDUSTRY INSIGHT

28

Within the climate change context, floods of increasing severity have become commonplace, requiring a range of engineered responses to manage rising stormwater volumes. IMIESA speaks to Scott Magnus, Contract Manager at BLOC Contractors – a leading geotechnical specialist – about an innovative solution employing handmined segmental tunnelling in Prospecton, Durban. P12 PIPE SYSTEMS

Easy guide to fixing leaks at home

12

36

BWUA demonstrates visionary leadership in ISO compliance

Industry Insight Isipingo’s dune tunnel provides stormwater relief

34

Water & Wastewater

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ON THE COVER

with retrofitted systems

37

Pumps New wastewater pump for local

Social Infrastructure | Schools

municipalities and industries

High-impact innovation. Arbeidsgenot Primary School development redefines future-proof education

Vehicles & Equipment 14

Powerful crushing performance on Limpopo road project

Sustainability An Arbor Month initiative. Urban greening with water conservation in mind

one piece

41

17

Cement & Concrete Colloidal silica makes durable concrete

The good, the bad and the most appropriate.

What makes a good material? And what characterises a bad one?

18

even more durable

42

Why cutting quality is cutting corners on SA’s future

44

Cement under the microscope:

Pipe Systems

Redefining building analysis

SAPPMA’s commitment to excellence helps build enduring infrastructure

22

Classification – the heart of thermoplastic pipes

24

A final salute to Dawie Botha

HDPE: The future of civil infrastructure in South Africa

26

Waste Management

Securing South Africa’s infrastructure: The thermoplastic pipe quality crisis

28

RAILWAY ENGINEERING

40

Church relocation completed in

Plastics in Perspective

32

38

45

In Memoriam 47

Municipal and industrial recycling ventures strengthen communities

37

WATER & WASTEWATER

48

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EDITOR’S COMMENT EDITOR Alastair Currie Email: alastair@infraprojects.co.za DESIGNER Beren Bauermeister CONTRIBUTORS Geoff Tooley, Ian Venter, Professor Mark Everard, Mike Smart, Thabang Byl DISTRIBUTION MANAGER Nomsa Masina DISTRIBUTION COORDINATOR Asha Pursotham SUBSCRIPTIONS Email: distribution@infraprojects.co.za ____________________________________________ ADVERTISING SALES KEY ACCOUNT MANAGER Joanne Lawrie Tel: +27 (0)82 346 5338 Email: joanne@infraprojects.co.za ____________________________________________

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ANNUAL SUBSCRIPTION: R805.00 (INCL VAT) ISSN 0257 1978 IMIESA, Inst.MUNIC. ENG. S. AFR. © Copyright 2025. 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: Narisha Sogan Tel: +27 (0)31 266 3263 Email: imesakzn@imesa.org.za NORTHERN PROVINCES Secretary: Lethale Magagane Tel: +27 (0)72 059 7444 Email: np@imesa.org.za SOUTHERN CAPE KAROO Secretary: Henrietta Oliver Tel: +27 (0)79 390 7536 Email: imesasck@imesa.org.za WESTERN CAPE Secretary: Michelle Ackerman Tel: +27 (0)21 444 7112 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 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.

Sound governance is the key to SA’s future

W

ithin every nation, the public service is a vital enabler that depends on a sustained tax base to keep all departments functioning. In South Africa’s case – as for most countries – government is the largest employer, with an estimated 1,7 million personnel employed. A high percentage work in essential services that include education, health, defence, policing, public administration, and built environment services.

The key issue is not about the numbers, but the return on investment for South African society and the point at which fiscal constraints become an inhibitor rather than an enabler when there are so many social and infrastructure priorities. This is underscored by National Treasury statistics, which reveal that the public service wage bill increased as a share of GDP from 5.6% in 1994/95 to 10.4% in 2023/24. In the same period, we’ve experienced a steady contraction in GDP growth.

We need to rebalance this equation.

To illustrate the point, based on July 2025 statistics around 6,17 million personnel are employed in the UK’s public sector, with the wage bill representing over 20% of total government spending. However, the UK ranks sixth in the world in terms of nominal GDP, while South Africa is in 41st position. The UK also has an unemployment rate of 4,7%, compared to South Africa’s approximately 33,2%.

It’s therefore essential that we have a realistic public and private employment ratio as we rebuild our economy.

Cutting the waste, boosting capacity The South African government acknowledges the challenges, focusing on cutting back on wasteful expenditure. That includes the inflated cost and unnecessary outsourcing of aspects like accounting services, which despite their widespread adoption have still often failed to yield clean audit results.

Allied to this is the need to revitalise public service performance by ensuring that those employed add value, are professionally equipped, and dedicated to ethical practices. This approach is defined by government’s Batho Pele (“putting people first”) mandate.

In regions like the European Union, a high percentage of those employed hold tertiary qualifications; we need to follow suit and ensure professional registration and accountability across all relevant disciplines.

Either way, we cannot afford to cut back on essential services – we need more specialists in every modern-day

Stemming industrial contraction At a higher level, we are also seeing the downstream impact of delays in revitalising South Africa’s rail and port infrastructure, the rapid escalation in energy costs, and a weak economy. A case in point is ArcelorMittal South Africa’s decision to close its Newcastle and Vereeniging long-steel operations, with some 3 500 direct jobs lost. The ultimate result is a further loss of much-needed industrial capacity to support the country’s macroeconomic objectives.

We cannot afford this, but we must also face the realities of global competition, and the attractiveness of cheaper import alternatives. At the same time, a free and fair trading environment must ensure that all products meet the highest compliance standards.

G20 partnership Strategic trade partnerships remain vital in navigating an evolving tariff market of increasing complexity. That’s why South Africa’s and the African Union’s membership of the G20 – comprising developed and developing countries – is so impor tant. We have an amazing opportunity to showcase our resilience and appetite for innovation as the G20 Presidency hosts of the 20th G20 Summit in South Africa during November.

Here excellence in governance is top of the agenda.

The reality is that without a vibrant public sector, no countr y can achieve meaningful socioeconomic growth. However, this is interdependent on an equal private sector partnership that is free to flourish.

That’s essential for growing the tax base needed to fulfil our transformation and broader UN Sustainable Development Goals, and strengthen public sector performance.

Alastair

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

IMESA

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

INFRASTRUCTURE DEVELOPMENT • SERVICE DELIVERY • ROADS • BUILDING • MAINTENANCE • ENERGY • WASTE

INDUSTRY INSIGHT Scott Magnus

Contract Manager at BLOC Contractors Isipingo’s dune tunnel provides stormwater relief

SOCIAL INFRASTRUCTURE

PIPE SYSTEMS

Primary school project showcases future-proof innovation

Classification – the heart of thermoplastic pipes

The ABC logo is a valued stamp of measurement and trust. IMIESA is ABC audited and certified.

discipline – but we must improve efficiencies in the infrastructure space that enable all meaningful progress, ensuring that allocated local government budgets are spent correctly. Delays in project awards and execution have a negative ripple effect that directly affects the construction sector in all its facets.

CEMENT & CONCRETE TECHNOLOGY Tests prove colloidal silica optimises durability

RAILWAY ENGINEERING Namibian line upgrade enhances SADC links

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.

Gabion Baskets

The masters in erosion mitigation and river management

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IMIESA September 2025

3

IMESA

PRESIDENT’S COMMENT

International knowledge exchange builds local best practice As we draw closer to South Africa’s 2026 Local Government Elections, one of the key factors swaying voters will be the existence or absence of municipal service delivery. In this respect, high-performing municipalities with proactive mayoral leadership standout due to their commitment to collaborative consultation with their in-house engineering teams.

S

patial planning and development are policy driven – and must be rolled out in consultation with communities and business – and in line with approved budget allocations. However, the resulting enabling infrastructure can only be achieved by empowering engineering leaders as equal stakeholders.

As IMESA, we have an expert understanding of the priorities and implementation requirements, but we fully appreciate that the public at large may not understand the nuances. In other words, who makes the big decisions. In leading towns and cities, we do once the plans have been greenlit – in conjunction with our built environment, supply chain, and financial colleagues.

The latter’s understanding and buy-in is crucial in enabling realistic, actionable budgets. That viewpoint is reinforced by past Auditor-General South Africa repor ts on local government outcomes, where infrastructure execution remains fragmented, despite adequate budget provision – within a currently constrained fiscus – to effectively build real value.

African member countries, as well as to expand the membership reach in key regions that include Asia and South America.

Each region and country face their own unique country-specific challenges within the common framework of the UN Sustainable Development Goals – and universally their municipal engineers are constantly lobbying for greater infrastructure support. In federal systems like the USA, for example, there have been growing calls for more interstate funding for aspects like dams, roads, and pipelines. Parallel examples exist within our Southern African Development Community.

Going forward, we plan to regularly publish municipal engineering case studies in IMIESA from within the IFME community, as well as sharing our local successes with affiliated publications worldwide. This will serve both as an inspiration and a valuable education process, particularly for aspiring graduates and young engineers who may not have considered a career in municipal engineering – whether in the public or private domain.

We need to rethink our approach IFME community Across the global municipal engineering spectrum there are key lessons that we can learn and apply within South Africa’s distinctive developed and developing context. An invaluable platform in this respect is IMESA’s membership of the International Federation of Municipal Engineering (IFME). The latter is dedicated to the exchange of technical and cultural information, innovations, and experiences among municipal engineers and public works professionals worldwide. Its diverse membership includes top tier and emerging economies, which in Southern Africa currently comprise South Africa, Botswana, Namibia, and Zimbabwe.

The collective goal within IFME is to incorporate a far greater representation of

4 IMIESA September 2025

The theme for our upcoming 88th IMESA Conference in East London during October 2025 is “Sustainable Engineering Solutions”. A core part of the presentations is driven by the understanding that we cannot solve our infrastructure issues with the same mentality that created them.

We need to create opportunities to experiment with new innovations.

Here municipal engineers are uniquely positioned to respond because they are exposed to the realities daily.

An example is the urgent need to get on top of the widespread failure in municipal Geoff Tooley, Pr Eng Hon FIMESA, IMESA President: 2024-2026

wastewater treatment works with a fresh design, operations, and maintenance approach that includes energy efficiency. Substantial investment will be required, and with it a rethink on the technologies and processes employed.

For our rapidly growing informal settlements and rural communities not currently connected to conventional waterborne services, one option could be the more widespread adoption of decentralised sanitation treatment.

These on-site solutions, which typically employ bio-based processes, provide a far more dignified approach to VIP alternatives. Plus, they also make provision for reuse for applications like toilet flushing and small-scale agricultural irrigation.

The vital role of academia It all comes down to fit-for-purpose solutions constructed around community needs. An interesting initiative from this standpoint is being pioneered by Dr Justin Pringle, a Senior Lecturer, Hydraulics and Environmental Fluid Mechanics at the University of KwaZulu-Natal. He has started an annual competition that requires students from all engineering disciplines to engage with the local community, identify a problem and develop a solution.

This is an excellent foundational methodology in creating a pipeline of socially conscious engineers.

It also provides an invaluable pool of low-tech and high-tech options that municipal engineers can trial and potentially apply in practice in conjunction with OEMs and the consulting engineering sector.

Worldwide, municipal par tnerships with academia are common, but in South Africa we need to gain more traction. This has a mutual benefit in terms of real-world research opportunities, rather than “blue sky” possibilities.

Forging the way, IMESA is currently engaging with various institutions that include IFME affiliated stakeholders to facilitate increased knowledge transfer.

Ultimately, our infrastructure challenges are immense; so too are the oppor tunities. As more funding becomes available, backed by engineering led expertise, we can and will make a major difference.

COVER STORY

GABIONS ARE THE CRITICAL INTERFACE

FOR RIVER MANAGEMENT

An artist’s impression of a typical weir layout, incorporating wingwall protection. Gabion Baskets makes extensive use of 3D animation to model and simulate its design proposals

As environmentally engineered structures, gabion systems have proven themselves worldwide as the preferred solution for riverine protection, embankment stabilisation and erosion mitigation.

IMIESA speaks to Louis Cheyne, Managing Director of Gabion Baskets, about the key advantages, citing recent case studies that showcase innovation.

E

rosion control is the critical factor – especially in urban scenarios – where the steady increase in stormwater run-off caused by town and city developments is placing unprecedented pressure on rivers.

This is being fur ther exacerbated by the increase in extreme flood events. The knockon effect is that riverfront properties, as well

as structures like bridges and roads face the risk of being undermined,” Cheyne explains.

It’s impor tant to understand that rivers will change their course over time, which is why their condition needs to be constantly monitored, and corrected with gabion inter ventions when needed. As Cheyne points out, it is also essential to carr ying out a hydrological study to determine known

and anticipated water velocities, taking into account existing flood line data, so that the gabion systems optimally perform their role now and in the future. This includes the installation of gabion wingwalls for channels and weirs to provide outflanking protection during major storm events.

“Another crucial consideration is ecosystem preservation. A prime example are wetlands that serve as vital habitats for fauna and flora, as well as performing a natural biofiltration function that helps to maintain downstream water quality. In this respect, our gabion fabrication and design recommendations place a major emphasis on holistic solutions.

This includes the integration of fishways in our weir designs, where required. These are typically pool-and-weir or vertical-slot designs that incorporate known water velocities and hydraulic jumps to accommodate specific fish species,” Cheyne continues.

Correct material specifications However, the foremost consideration when designing and constructing riverine structures – such as channels, groynes, weirs and mass gravity walls – is correct material specification. SANS 23-3:2020 sets the standard locally and globally for the correct manufacturing specification for

GEOTEXTILE – F-34 OR SIMILAR APPROVED

A longitudinal weir cross-section. The gabion wall is founded on a gabion mattress which extends to form part of the channel lining system. The latter slows down water velocities, as well as countering scouring caused by the hydraulic jump. Concrete capping at the spillway crest reduces the risk of debris impact damage

6 IMIESA September 2025

COVER STORY BEFORE

AFTER

CHANNEL LINING The installation of gabion mattress channel systems provides a sustainable response to stormwater erosion

hexagonal double-twisted woven mesh steel wire gabions and revetment mattresses.

In turn, SANS 1200 DK:1996 governs the correct installation techniques for gabion systems.

All woven mesh gabions produced at Gabion Baskets’ manufacturing facilities meet Class A galvanised wire specifications as the minimum standard, with the added option of a PVC coating for more corrosive conditions,

and for submerged gabion structures.

Depending on the hydraulic conditions, a larger diameter wire may be required for extra strength.

In many cases, Gabion Baskets’ project management division has been called in to investigate and remediate failed installations where one of the prime causes is a non-compliant wire specification. This

UPINGTON RIVER WALL

is often compounded by poor installation techniques, and incorrect fill materials.

“Gabions are highly effective because of their built-in permeability and the ability of the wire to flex in countering hydraulic flows and absorbing debris impact. However, the rock selected must be suitable and packed correctly to achieve an approximately 35% void composition. We’ve seen scenarios where building rubble has been employed in rivers – a guaranteed recipe for subsequent structural failure because these materials will break up within a relatively short space of time,” Cheyne explains.

Founding conditions and channel linings

A bird’s eye view of a 6 m high river wall bordering the Orange River in Upington, which was constructed in 2011. Gabion Baskets provided a design recommendation, materials and project management services A side perspective: the wall was overtopped during a major flood in 2024, but when the water levels subsided the structure was still perfectly intact

Founding conditions are equally vital to suppor t submerged mass gravity walls resting on riverbeds, and to prevent scouring and undermining within typically clayey soil conditions. Here gabion mattresses are employed, extending out from the toe of the wall for a predetermined distance. The mattresses also make provision for a degree of variable settlement without the risk of a slip or overturning where the retaining wall has the correct degree of batter to ensure structural stability.

Gabion mattresses are also commonly used for channel lining where their primary role is to slow down water velocities, and again the correct specification is key for long-term performance. The rate of velocity control is determined by the thickness of the mattress, the rock size and type, packing technique, plus the secure wire lacing of the mattress lid and allied connections. Smaller rock that can escape through the mesh openings must be avoided. “We’ve seen scenarios where the gabion lid is ripped

IMIESA September 2025

7

COVER STORY

THE RIVER CLUB GOLF COURSE WEIRS, GAUTENG Preparing the mattress foundation for one of the weir structures at the The River Club Golf Course. The employment of geotextiles forms an essential component to mitigate soil loss and control the designed degree of permeability

Advanced construction on Weir 1 (above) and the completed structure (below). This measures 9 m in length, 1 m in width, and 2 m in height and is the primary weir, forming part of five integrated weirs constructed at the The River Club Golf Course

Weir 3 measures 6 m in length, 1 m in width, and 2 m in height and incorporates a stormwater channel

of f when the incorrect procedures have been adopted, completely compromising the installation,” says Cheyne.

“The point to emphasise is that gabion construction is a highly specialised field of civil engineering and should only be carried out by suitably qualified engineers and contractors. Aside from health and safety risks, and the rework cost for remediation, poor practice frequently ends up causing more environmental damage,” Cheyne explains.

The River Club Golf Course weirs A recent project completed by Gabion Baskets at the The River Club Golf Course in Sandton, Gauteng serves to underscore how a professionally designed system comes together to achieve an optimal balance between environmental stewardship and aesthetics.

8 IMIESA September 2025

The scope of works entailed the strategic installation of five meticulously designed weirs and associated channel improvements on sloping terrain, aimed at optimising water flow dynamics, enhancing the landscape, and contributing to the estate's overall environmental management.

Completed within a two-week timeframe, the construction programme required an estimated 140 m3 of excavation to prepare the sites and ensure the structural integrity and proper functioning of each weir as part of an interconnected system The construction of the primar y weir (Weir 1) necessitated extensive preliminary excavation to achieve the required ground level, accounting for a substantial portion of the project's total excavation volume. This structure measures 9 m in length, 1 m in width, and 2 m in height.

Following in succession, Weir 2 is sized at 8 m in length, 1 m in width, and 2 m in height, while Weirs 3 and 4 measure 6 m in length, 1 m in width, and 2 m in height. The smallest in the series – Weir 5 – measures 4 m in length, 1 m in width, and 2 m in height.

In addition to the weir installations, the construction of a robust channel system was an essential requirement. This involved the deployment of 4 x 2 x 0.3 m mattresses, designed to reinforce the channel bed and banks, thereby preventing erosion and ensuring stable water conveyance.

Furthermore, at the outlet of the channel, on each side, specialised directing structures were installed, measuring 2 m in length, 0.5 m in width, and 0.5 m in height.

These strategically placed structures are instrumental in guiding the water flow efficiently towards the main river and over

COVER STORY

the newly constructed weirs, optimising the water's path and minimising turbulence.

“Ever y installation has its own unique requirements and we’re proud to have delivered a solution that meets the high standards expected at such a distinguished property. The weirs and channels blend in so well, enhancing the built environment. Plus, the weirs create mini reservoirs for birdlife and animals,” says Cheyne.

Parkhurst river wall In addition to greenfield projects, Gabion Baskets is often involved on installation upgrades. Typically, the erosion measures need to be further enhanced due to escalating flood damage.

A case in point is an extension to a mass gravity river retaining wall designed to protect the embankment under a bridge in Parkhurst, Johannesburg. The original wall was installed by a Gabion Baskets approved contractor some 18 years ago and is still structurally sound. However, this now needed to be extended by a further 10 m to counter further erosion.

Once the 2 m high extension had been completed, 144 m 3 of suitable backfill material was carefully placed and compacted behind the gabion wall. This backfill serves multiple essential functions: it provides lateral support to the structure; integrates the wall seamlessly with the existing topography; and helps to manage subsurface water flow,

PARKHURST RIVER WALL, GAUTENG A 10 m gabion river wall extension was required to counter severe embankment erosion underneath a bridge in Parkhurst, Johannesburg. This provides added protection for the bridge structure and protects a bordering property from being undermined

further contributing to the long-term stability of the entire system.

Walls that stand the test of time The larger the river, the greater the need for precision engineering and exacting material selection, and among southern Africa’s most challenging are the mighty Orange and Zambezi Rivers. Here Gabion Baskets has provided design recommendations, project management, training provision, and gabion supply for a series of landmark projects.

One of its longstanding installations is a 6 m high river wall bordering the Orange River in Upington. Constructed in 2011, this wall has relentlessly withstood rising flood levels of increasing severity. In 2024, the river burst its banks and overtopped sections of the wall, but when the floods subsided it was still perfectly intact. Gabion Baskets is now supplying a solution for a neighbouring property.

Further afield in Zambia, Gabion Baskets has provided integrated solutions for various private tourism entities that include the Musango River Lodge, and Lolebezi Safari Lodge. Both entailed embankment reinstatement, protected by mass gravity wall retention, with varying heights up to 4 m.

Combatting erosion is a collective responsibility

A perspective of the completed wall extension. The backfill behind the wall enhances lateral support and serves as a platform for landscaping

“Soil loss through erosion has multiple downstream impacts that extend from land degradation to excessive sediment build up in rivers and reservoirs that negatively affect water quality and riverine habitats.

The critical starting point in reversing these threats is proactive catchment management, which requires a combined response from all stakeholders,” adds Cheyne.

“Central to this process is a renewed focus on stormwater management through responsible built environment practices that take the pressure off our rivers. Flood risks will always be there, but with innovative environmentally engineered solutions we can significantly reduce them, while working towards climate change mitigation goals,” Cheyne concludes.

www.gabionbaskets.co.za

IMIESA September 2025

9

IMESA

SMART INFRASTRUCTURE

REQUIRES A COLLABORATIVE RESPONSE Representing the largest member footprint in South Africa, IMESA’s Northern Provinces (NP) Branch incorporates the Gauteng, North West, Limpopo and Mpumalanga provinces. Comprising a mix of metros and secondary cities, this region encompasses a major percentage of South Africa’s economy, making effective infrastructure delivery a crucial component.

O

n 29th August 2025, the NP Branch held its annual Technical Seminar and AGM, with a strong attendance by members and delegates from across the private and public sector – all dedicated to supporting IMESA’s quest for capacity building and the highest levels of professionalism in municipal engineering.

Opening the event, Kwena Maphoto, IMESA NP Branch Chairperson, stressed the importance of delivering infrastructure that empowers society. “We know that infrastructure across South Africa is under tremendous strain, which is being felt daily in terms of factors such as water disruptions, power failures and potholed roads that add to growing community frustrations.

“As municipal engineers we understand the challenges, and our collective focus must be

on finding smart solutions for practical quick wins. That requires the widespread adoption of digitalisation to design, manage and operate services in real-time in collaboration with academia, technology providers and the built environment community.”

Delegates in attendance at the IMESA NP Seminar and AGM

on decades of research and applied experience within the town and regional planning arena.

As he expanded, a key element for future success is access to accurate spatial data and the expertise to meaningfully analyse it at local government level for infrastructure implementation. He said the responses must be sustainable and enabled by practical regulations that facilitate municipal autonomy, as opposed to national overregulation. Another key issue highlighted was the clear need for local government financial health to execute capital budgets, with engineers a vital part of the process. However, accurate decisions hinge on real-world information on the ground.

Keynote presentations These viewpoints were reflected in the three Technical Seminar addresses presented respectively by Burgert Gildenhuys, Director at BC Gildenhuys & Associates; Devesh Mothilall, Head of Digitalisation: Smart City Office and Head of Knowledge Hub – ECOE, City of Johannesburg; and Refiloe Mokoena, CSIR Senior Researcher within the Smart Mobility Cluster.

Gildenhuys’ talk was entitled “Reclaiming Local Government: Municipal Service Delivery, Planning and Institutional Challenges”, based

Water 4.0 Next up, Mothilall’s presentation was entitled “Water 4.0: Digital Transformation in Water Resource and Utility Management”, aimed at creating intelligent systems that are resilient, cyber secure and futureproof for ensuing generations. The burning issue is non-revenue water losses, which on average exceeds 35%, but is generally much higher.

As Mothilall pointed out, this poses a major threat within the context of ageing infrastructure that unless immediately tackled

From left: Devesh Mothilall, Head of Digitalisation: Smart City Office and Head of Knowledge Hub – ECOE, City of Johannesburg (speaker); Khodani Tshovhote, IMESA NP Branch Committee member; Kwena Maphoto, IMESA NP Branch Chairperson; Refiloe Mokoena, CSIR Senior Researcher (speaker); Burgert Gildenhuys, Director, BC Gildenhuys & Associates (speaker); Linda Tyers, IMESA NP Branch Treasurer; Vuyani Gxagxama, IMESA NP Branch Council Liaison and IMESA Vice-President: Technical; and Khomotso Mdhluli, IMESA NP Branch Secretary

10 IMIESA September 2025

IMESA

New IMESA Council members who attended the Seminar and AGM receiving their “badge of office” from Vuyani Gxagxama, IMESA NP Branch Council Liaison and IMESA Vice-President: Technical. From left are: Molahlehi Marate, Associate Principal, Atana; Khodani Tshovhote, Project Manager: Roads and Stormwater, City of Tshwane; and Teniel Ramjogi, Director, TR Infinity

will undermine socio-economic development against a backdrop of unprecedented population growth and urbanisation. That requires a response well beyond traditional engineering approaches, which must be driven by greater information and communications technology (ICT) adoption.

The benefits of ICT include Ar tificial Intelligence and Machine Learning that can leap-frog decades of incremental improvements – something South Africa needs right now. This will be supported by devices like smart metering that help utilities manage real and apparent losses via automated leak detection. A series of projects within the City of Johannesburg – in partnership with the University of Johannesburg – have yielded measurable improvements, with downstream implementation opportunities for other municipalities.

Smart roads As the concluding speaker, Mokoena’s presentation – “Emerging Technologies in Road Design for Smart Municipal Infrastructure” – spoke on one of the most enabling platforms for meaningful growth, namely transportation.

Two specific innovations highlighted were the use of recycled plastic waste for asphalt

production based on trails using the CSIR’s heavy-vehicle simulator, which has proven the durability benefits and promotes a circular economy; and the specification of climate resilient performance grade bitumen products – factoring in evolving atmospheric temperature impacts by geographic region – to optimise asset life. The latter methodology has been refined by purpose-designed software.

These interventions, among others, are vital in managing finite resources and in reducing maintenance inter vals, as well as new construction costs. Future implementation will require ongoing industry collaboration.

AGM feedback Following the presentations, the AGM report recorded the gains made by the IMESA NP Branch over the past 12 months. In delivering on its professionalisation mandate, a series of roadshows in conjunction with representatives from the Engineering Council of South Africa (ECSA) took place to promote member registration.

Four CPD accredited training programmes were also successfully hosted on topics that included advanced hydraulic modelling, and project management. Additionally, some

A strong showing of women leaders in municipal engineering at the IMESA Northern Provinces Branch’s 2025 Technical Seminar and Annual General Meeting

1 000 learners were engaged at secondary level to highlight municipal engineering career opportunities, alongside partnership agreements concluded with various universities.

“We have now also incorporated the highly successful IMESA Young Professionals Portfolio (YP2) model first initiated by our KwaZulu-Natal Branch, to support and grow our membership base in this vital segment,” said Maphoto.

Overall, the NP Branch membership base grew from 374 to 432, underscoring its successful outreach endeavours across municipalities, as well as at tertiary level.

“The journey ahead is clear. We need to recapacitate our municipalities, reinforce commitment and accountability, and re-professionalise the public sector to safeguard quality ser vice deliver y. This is a shared responsibility across multiple stakeholder platforms, with IMESA leading the charge in municipal engineering,” Maphoto concluded.

To obtain copies of the speaker presentations, email the IMESA Branch Secretar y at np@imesa.org.za.

IMIESA September 2025

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INDUSTRY INSIGHT

ISIPINGO’S DUNE TUNNEL PROVIDES

stormwater relief

Within the climate change context, floods of increasing severity have become commonplace, requiring a range of engineered responses to manage rising stormwater volumes. IMIESA speaks to Scott Magnus, Contract Manager at BLOC Contractors – a leading geotechnical specialist – about an innovative solution employing hand-mined segmental tunnelling in Prospecton, Durban.

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he widespread April 2022 floods have been recorded as KwaZulu-Natal’s worst natural disaster to date, with eThekwini Municipality being one of the worst affected areas. In the wake of the devastation, billions of rands in infrastructure damage were caused, with a much greater multiplier effect in terms of economic losses.

In response, eThekwini’s Engineering Unit: Coastal, Stormwater & Catchment Management Services, responded citywide with repair works and future-proof interventions to effectively mitigate against recurring flood events.

A case in point is the town of Isipingo south of Durban, which includes Prospecton – a strategic industrial and manufacturing hub. An urgent upgrade was required to the Isipingo canal system, which flows into the Isipingo Beach lagoon. This led to the initiation of the Clark Road Sea Outfall and Culvert Stormwater Upgrade.

The scope of works – completed over an eight-month period in July 2025 – entailed the construction of a new 92 m long 2 650 mm diameter (2 400 mm internal diameter) stormwater segmental concrete tunnel, traversing through an approximately 20 m high sand dune section and

BLOC Contractors’ custom-built jacking shield employed on eThekwini Municipality’s Clark Road Sea Outfall and Culvert Stormwater Upgrade project

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interconnecting with a new stormwater outfall on the beach.

BLOC Contractors was appointed as the geotechnical sub-contractor, working in conjunction with Afrostructures as the main contractor. The latter was responsible for the precast concrete fabrication of the 50 MPa individual segments required to build the 153 rings forming the completed tunnel system. Manufactured to strict standards to meet strength and dimensional accuracy, Afrostuctures also designed an innovative interlocking mechanism to facilitate ease of installation. Each ring is composed of eight individual 600 mm wide elements.

Trenchless versus open excavation Open excavation was not a practical option, firstly due to the depth of the dune, and secondly given the presence of nearby flats running parallel to the servitude in which the pipe needed to be installed. Plus, there was an informal settlement living on the dunes that had to be temporarily relocated to make room for the tunnel launch pit.

Mass excavation would also have required extensive shoring, which would have been too expensive, as well as impractical in the shifting sands. Given the challenging ground conditions and high water table, the traditional pipe jacking method was also unsuitable, as the tunnel's size and length, and the resulting ground pressures, posed a significant risk that the jack could seize before being completed.

Another option that could have been considered by the client is closed faced microtunnelling, but the cost would have been around three times higher than the final method chosen. Therefore, BLOC Contractors’ proposal for a hand-mined segmental tunnelling approach was supported by the client.

INDUSTRY INSIGHT In developing the optimal tunnelling methodology, BLOC appointed Clive Wilson from Wil-Pass and Associates for the geotechnical and structural design of the overall system, as well as the segmental sections.

“His expertise was essential in developing and presenting a design that was both feasible and safe, ensuring the project could be delivered successfully on time and within budget,” Magnus explains.

Custom-built shields Since its formation in 2002, BLOC Contractors has completed more than 200 projects, fielding a range of services that include pipe jacking, horizontal directional drilling, lateral support, and sheet piling. The company also has the inhouse capability to design and fabricate fit-forpurpose equipment solutions. For the Clark Road project, this entailed the development of a specific custom-built shield.

“Shields typically used for pipe jacking and tunnelling projects are not items that you can generally buy as standard products ‘off the shelf’ on the open market. However, thanks to our inhouse knowledge and expertise we have a wellestablished track record for mechanical innovation.

This gave us the confidence to adopt a hand-mined segmental tunnel methodology for the Clark Road stormwater outfall,” Magnus continues.

“Our unique shield for this project had to seamlessly accommodate the segments and be strong enough to push forward under high jacking loads through loose and wet sand, while maintaining precise alignment, all of which it managed perfectly. To the best of our knowledge,

Over 500 m3 of beach sand needed to be removed to complete the 92 m long tunnel, which was carried out using manual excavation

Cooled air was constantly pumped into the tunnel to maintain a comfortable working temperature. The site’s high water table also required constant dewatering at the face

In total, 153 precast concrete rings were installed to build the 92 m long stormwater outfall tunnel. Each ring is composed of eight individual 600 mm wide segments

this technique has not been used in South Africa for more than 20 years, largely due to the loss of industry experience. It’s also a first for us, underscoring our ability to innovate,” Magnus continues.

In total, over 500 m3 of beach sand needed to be removed to complete the tunnel, with the material removed via a trolley system equipped to handle around 1,2 m3/load.

“The project was a great success and a vital one for Prospecton, which forms part of the Durban South Basin – a low-lying area that has been prone to periodic flooding over the years,” says Magnus.

“The Clark Road outfall is the final stormwater conduit to the sea within Isipingo, and therefore essential.”

“From a creative engineering perspective, this project has also demonstrated how homegrown solutions can extend the possibilities of conventional pipe jacking techniques safely and cost-effectively. Hand-mined segmental tunnelling could well become the norm on municipal projects where similar ground conditions exist,” he adds.

Launch technique During construction, the 2 650 mm diameter segmental tunnelling shield was hydraulically advanced forward to incrementally install the precast concrete segments. However, unlike in soil and rock conditions – where a front face drilling arm could have been employed – in this case the sand was manually removed by BLOC Contractors’ construction team. Since the pipe needed to be jacked on a downhill grade in saturated conditions, provision also needed to be made for continuous dewatering of the face.

“When you jack through compacted soil, engineered fill or rock, the ground naturally arches into a round protective shape, enabling you to push your pipe forward. However, loose beach sand continuously collapses. As you advance, the sand settles and closes in around the pipe being installed,” Magnus explains.

If a conventional pipe jacking approach was applied under these circumstances, the friction load would become unsustainable over a 92 m distance, resulting in damage to the pipe sections, and potentially the seizing of the hydraulic jacking mechanism.

For the Clark Road project, the front shield was pushed forward 600 mm each time – per installed segment. The rear skirt on the tunnelling shield – extending around 1,5 m over the last pipe section placed – provided space for the crew to assemble the next ring within a safely controlled environment.

As the work was carried out during summer, cooled air was pumped into the face to keep working conditions optimal.

Pipeline projects In parallel with the Clark Road tunnel development, over the past 12 months BLOC Contractors has been involved on a wide range of water and sanitation projects in South Africa and Namibia.

“It’s really encouraging to see a positive upturn in regional public infrastructure investment. In response, we’ve recently added microtunnelling to our suite of services to support a series of exciting projects in the pipeline. In expert hands, trenchless techniques minimise disruptions and add enduring value in a way unmatched by opencut techniques,” Magnus concludes.

www.bloc.co.za

IMIESA September 2025

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SOCIAL INFRASTRUCTURE | SCHOOLS

HIGH-IMPACT INNOVATION

Arbeidsgenot Primary School development redefines future-proof education A bird’s eye view of the school complex, situated within the rapidly expanding Grasslands community

flexible furniture solutions allow easy adaptation for diverse learning and mobility needs.

Another key feature is the multi-purpose school hall, which was strategically designed to be accessible to the broader community while remaining securely separated from academic areas, ensuring the safety of school facilities during after-hours use.

Green elements

The construction of the new Arbeidsgenot Primary School in Grasslands, Bloemfontein, is a milestone development for a community that has long endured inadequate access to basic education. Originally a small, under-resourced isolated farm school, the old facility was unable to meet the growing demand for education in the area. Outside the city limits, learners were forced to travel long distances to attend school.

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ompounding this, most public schools in Mangaung are overcrowded, with some classrooms accommodating 50 to 60 learners – conditions that significantly affected the quality of teaching and learning.

Jointly commissioned by the Free State Department of Education and the Development Bank of Southern Africa (DBSA), this project responded directly to these long-standing challenges to construct a Mega school that will accommodate 1 200 learners. SMEC South Africa was appointed by DBSA to provide professional services spanning the full project lifecycle – from preliminar y and final design to construction super vision and close-out.

This included civil, structural, mechanical, electrical, water, and sanitation ser vices.

14 IMIESA September 2025

SMEC was also tasked with ensuring that all designs met national building codes and education sector standards.

Optimally combining form and function, the school complex showcases excellence in design and construction. It also goes well beyond this by creating a learning environment that keeps pace with future educational requirements in an increasingly high-tech world.

A case in point is the provision of a computer and a science laboratory – facilities still not commonly provided at primary level in South African public schooling.

Classroom capacities are now much smaller, and more teacher focused, and every provision has been made to facilitate engagement. This includes the provision for wheelchair access via appropriately sloped ramps. Furthermore,

To reduce the carbon footprint, lower operational costs, and enhance comfort levels, natural ventilation and building orientation were carefully planned to optimise airflow and limit reliance on mechanical systems.

In collaboration with the architectural team, all classrooms were designed with elevated aluminium-framed windows, carefully positioned to maximise daylight penetration throughout the school day. This passive lighting strategy significantly reduces the school’s reliance on artificial lighting. Where lighting is required, energy-efficient LED fittings were installed throughout the facility.

Being a water-scarce region, the design also placed a major emphasis on conser vation measures. These include the installation of low flow taps, toilets, and urinals across all ablution areas.

Plumbing systems were designed for efficiency and provision was made for situations where the local municipality cannot supply water. Part of the design included a 65 000 ℓ water storage tank that can supply the school with enough water in the absence of water supply from the municipality. The storage tank also supports irrigation – ensuring the school can adapt to changing environmental conditions and water availability.

A safe environment Safety and security were primary considerations.

Here the footprint layout includes well-defined vehicular and pedestrian routes, a secure dropoff zone and spacious parking. Additionally, covered walkways connect all key buildings,

SOCIAL INFRASTRUCTURE | SCHOOLS

Face brick was used as the primary exterior finish across all buildings, chosen not only for its durability, thermal efficiency, and low maintenance, but also for its clean, timeless aesthetic

while dedicated play areas and outdoor seating were incorporated to support learner wellbeing beyond the classroom.

The inclusion of a guardhouse, an alarm system and CCTV surveillance ensures the protection of infrastructure and occupants – features rarely implemented in similar contexts. Enhanced measures were also implemented for the computer lab, including a reinforced steel door and ceiling-mounted steel mesh to deter theft and vandalism.

School hall design The school hall stands out as a particularly demanding element. Rather than conceal the structure with a ceiling, the team opted to expose the trusses, showcasing their geometry and varying sizes as an intentional part of the interior aesthetic.

Unlike more conventional finishes, the hall’s exposed concrete columns also had to

be cast to a smooth, uniform finish without any need for plaster or cladding. This placed considerable emphasis on workmanship and formwork preparation, as the visual result was entirely dependent on the accuracy and care taken during pouring.

The hall roof, too, introduced additional challenges: the large steel trusses were manufactured off-site but needed to be fitted with exacting precision on-site. Ensuring seamless integration between prefabricated and in-situ elements required a high level of accuracy and planning.

Working within tight budget parameters, the design team also opted to eliminate traditional gutters and downpipes, recognising their vulnerability to damage and ongoing maintenance costs. Instead, the roof design safely manages runoff while simplifying the structure – an elegant, cost-saving measure appropriate for a facility with limited resources.

The focal point for school activities, Arbeidsgenot Primary School’s hall also serves as a hub for community events

Visual harmony A strong emphasis was placed on visual harmony and consistency throughout the design and construction of the Arbeidsgenot Primary School. During site investigations, challenging soil conditions were identified, prompting the use of raft foundations across all buildings and the impor tation of G6 material to ensure structural stability, which provided an effective and practical solution.

In turn, durable, low-maintenance materials were used for major building elements such as flooring, walls, and roofs, which helps reduce future repair and replacement costs.

Simplicity and accessibility were fur ther prioritised in the design of all service systems, ensuring ease of upkeep and ready access for routine maintenance.

Creating a warm and inviting effect, face brick was used as the primar y exterior finish across all buildings, chosen not only for its durability, thermal efficiency, and low maintenance, but also for its clean, timeless aesthetic. To enhance visual

Rather than conceal the structure with a ceiling, the team opted to expose the trusses in the school hall, showcasing their geometry and varying sizes as an intentional part of the interior aesthetic

SOCIAL INFRASTRUCTURE | SCHOOLS

approach was applied, where practical, in locally sourcing the multifaceted materials required during the building programme.

Making a lasting difference

A section of the school’s pause area In collaboration with the architectural team, all classrooms were designed with elevated aluminium-framed windows, carefully positioned to maximise daylight penetration throughout the school day

appeal, two complementary brick colours were selected and intentionally arranged to break monotony and create a vibrant, inviting atmosphere.

The installation of insulated roofing within the classrooms further assists in regulating internal temperatures. In turn, the building envelopes and shading elements were tailored to suit the regional climate, ensuring long-term comfort and durability.

Community works Throughout the project, more than 100 jobs were created, prioritising local labour.

Workers received targeted training in trades such as plumbing, carpentry, bricklaying, and electrical works, along with health and safety, site supervision and entrepreneurial skills.

Financial literacy and life-skills sessions fur ther suppor ted long-term personal development.

In turn, local SMMEs were subcontracted for various aspects of the build, creating short-term income and strengthening small business capacity in the area. The same

Constructed over a 24-month period from July 2022 to July 2024, the establishment of the Arbeidsgenot Primary School has had a profound and positive impact on educational access and learning outcomes for children in the Grasslands community.

Previously, many learners walked more than 5 km each way to the old farm school – a physically demanding and sometimes unsafe journey that contributed to absenteeism, fatigue, and reduced learning capacity. The new school, now situated in the heart of Grasslands, is within comfortable walking distance for most learners – removing a vital barrier to foundational learning.

The school’s proximity has also strengthened parental involvement and deepened community engagement, enhanced by the opening of the school hall to the public for scheduled events. The latter now serves as an important social hub.

For example, in April 2024, Arbeidsgenot Primar y School hosted a Gender-Based Violence and Femicide Prayer Service, as well as the Provincial Freedom Day celebration – a clear reflection of the school’s evolving role as a space for healing, empowerment and collective progress. Events such as these reinforce the school's function beyond education, serving as a platform for awareness, advocacy, and civic participation.

Going for ward, the engineering layout includes provision for three additional classrooms. This planned flexibility ensures that the school can expand sustainably as the demand for early education increases in the area.

For current and future parents, it’s reassuring to know that their children have a solid and safe environment in which to grow in preparation for the next phases in their secondary and tertiary education.

The school’s play area creates a healthy balance between classroom tuition and outdoor recreation

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Covered walkways interconnect all key buildings

SUSTAINABILITY

AN ARBOR MONTH INITIATIVE

URBAN GREENING WITH WATER CONSERVATION IN MIND

Trees make cities more attractive, encouraging outdoor activities and social cohesion

South Africa is experiencing a steady rise in urbanisation, leading to increased population densities in cities, towns, townships, and informal settlements. This overcrowding often results in environmental degradation, par ticularly in areas where provision has not been made for parks, street trees, and open green spaces.

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apid urban development is frequently marked by inadequate environmental planning. However, effective planning – especially through initiatives such as urban greening – can play a vital role in enhancing the quality of urban environments and improving the well-being of residents.

To tackle this challenge, the Department of Forestry, Fisheries and the Environment (DFFE) has launched its 1 Million Trees campaign this Arbor Month (September 2025), under the theme “My Tree, My Oxygen, Plant Yours Today”. This is a key initiative under the Presidential 10 Million Trees Programme that encourages citizens, businesses, industry, labour and civil society at large to plant ten million trees (60% fruit and 40% indigenous) FIGURE 1

across the country. The DFFE has also published a tree catalogue (https://10milliontrees.dffe. gov.za/10milliontrees/make-a-pledge) to guide in the selection of suitable species based on specific demographic regions and to support their campaign through donations.

To strive for sustainability, it is crucial that proper tree planting and ongoing maintenance are considered in any tree planting project. During the first weeks of establishment, young trees typically need frequent watering – sometimes every few days in the first month – to anchor their roots. However, it is equally important to practice water conservation during this process.

Using methods such as mulching, drip irrigation, or water-wise planting techniques helps reduce evaporation, ensures efficient water use, and prevents wastage. As trees mature and their roots strengthen, the frequency of watering should be reduced, encouraging resilience while supporting sustainable water management. As we strive to create “Greener Communities”, let us be mindful of how we water our trees.

Follow these simple steps (as shown in Figure 1) to plant trees the Water Wise way:

5 Measure one spade-length in distance 6

7

8

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around the tree. In this area, remove all the grass and weeds.

Next to the tree’s roots, place a 2-litre plastic bottle with a hole at the bottom. Make sure the bottle is placed at an angle. Alternatively, a pipe can be used as a watering apparatus where water flows through and directly reaches the roots for efficient water uptake.

Ensure that the other opening end of the bottle/pipe is above ground level.

Add a 10 cm layer of mulch (leaves, stones, straws or strips of newspapers). Mulch acts as a blanket covering the soil; it keeps the soil cool and reduces water loss from its surface. Make sure that the mulch does not touch the tree.

Fill the bottle/pipe with water once a week.

This prevents wastage by sending water straight to the root system. Once you have watered the tree, put the lid on the bottle to prevent any water evaporation. After the first year, water the tree only when the soil is dry.

S ome plants grow towards the sun, therefore place your stake in the opposite direction of where the morning sun will emerge. Position a wooden stake of 3 m in length approximately 30 cm from the base of the tree. Insert the stake into the soil at a depth ranging from 20 cm to 60 cm. Gently fasten the stake to the tree's trunk using a soft material, like a used stocking. This will aid in promoting the tree's upright growth.

1 Dig a square hole, half a metre wide by half 2 3 4

a metre deep. Keep the dark topsoil (containing essential nutrients) separate from the soil beneath it. Put the topsoil in the bottom of the hole.

Dampen the soil with water to avoid any shock that could be experienced by the roots.

Remove the plastic bag and place the tree upright in the hole.

To enhance the nutrition of the soil, mix compost/kraal manure with your leftover soil and pack it firmly in the hole.

Always be #WaterWise! www.randwater.co.za | 0860 10 10 60

IMIESA September 2025

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PLASTICS IN PERSPECTIVE

THE GOOD, THE BAD AND THE

MOST APPROPRIATE

What makes a good material? And what characterises a bad one?

Material use throughout history and prehistory has been central to human progression. From the Stone Age, through the Bronze and Iron Ages, innovations were made possible by the properties of novel materials. As the old saying goes, we didn’t exit the Stone Age because we ran out of stones! Rather, the spirit of human ingenuity drove us to explore better ways to meet our diverse needs for shelter, hunting and defence, food production, transport, medicine, communication, water management, energy and many other facets that defined civilisations and supported our continued development. By Professor Mark Everard*

P

Professor Mark Everard’s book entitled Seeking Sustainable Development on a Level Playing Field: A PVC Case Study addresses “good” and “bad” scenarios in a balanced way, within the context of risk across the full societal lifecycles of the products into which it is incorporated

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lastics, of course, have been in the crosshairs of campaigners over recent decades. There is an irony that objectors make their voices heard through social media using computers, cell phones and other devices – even pens, televisions and printing machinery – made possible through the benefits of modern materials. This includes semiconductor-based microprocessors without which the space age, the ICT revolution and medical imaging would have been infeasible, a diversity of exotic metals and novel ceramics and, of course, plastics.

Many fail to realise quite what plastics are, and how much they support their needs as they turn on the tap, flush the toilet, make phone calls, use the internet, wipe their kitchens clean, switch on the computer or domestic lights, travel, or enjoy the comfort of high-efficiency insulation in windows and other domestic fittings.

Recreationally, wetsuits, fishing line, binoculars, breathable fabrics, waterproof bags, safe food storage and so many more plastic products add to the quality of modern life.

While pressing issues of potentially problematic additives, lack of recycling leading to waste

Professor Mark Everard

accumulation and generation of microplastics need to be addressed, a parallel and significant reality is that plastics make modern life possible in ways that are often unappreciated by those that rail against them.

None of this is necessarily news to readers of this magazine. We can though fall into the trap of regarding or selecting materials framed by a simple dichotomy of “good” versus “bad”, reinforced by a naïve regulatory environment and lazy media focused narrowly on potential hazard. We will return to the difference between hazard and risk later in this article.

Balancing the real-world elements Every breath we take comprises 79% inert molecular nitrogen as well as around 20%

PLASTICS IN PERSPECTIVE

oxygen vital for our health and wellbeing. These, of course, are good materials! But scuba divers are trained that nitrogen turns into a narcotic below certain depths when partial pressures are exceeded, and more critically that oxygen in enriched air mixes can turn instantly neurologically fatal if critical partial pressure thresholds are exceeded, with fatalities occurring every year as narcotised divers lose orientation or through oxygen poisoning.

So, these “good” materials are actually pretty “bad” in different contexts! And then we have hydrochloric acid, a pretty bad substance in environmental terms – “muriatic acid” was the initial focus of the UK Alkali Act of 1863: the first regulation globally on chemical releases from industry – and yet each and every one of us is producing HCl in our stomachs at a pH of between 1.5 and 3.5, where it is essential for decontamination and digestion processes and is then safely resorbed.

Ozone in the wrong place is carcinogenic and smog-forming yet is vital for deflecting and absorbing ultraviolet radiation in the upper atmosphere and is also useful for sterilisation of swimming pool water and for other purposes.

How useful is a naïve branding of “good” versus “bad” substances when context is overlooked?

This is more than a mental exercise.

Subconscious division of substances into the “good” and the “bad” pervades a great deal of chemical legislation and many supporting assessment tools relating to the industrial and domestic uses. This oversimplistic dichotomy certainly underpins the current hue and cry about plastics. The debate is at least more nuanced in the field of medicine, where a balance is sought between beneficial therapeutic properties versus contraindications.

Degrees of green The PVC window frame that I’m sitting by

as I type this article is a classic example. Green campaign groups might have me choosing timber as it can be sourced from renewable forests through excellent accreditation schemes such as the Forest Stewardship Council (FSC)1 that is also protective of forest dwelling communities. However, wood is biodegradable and so is often pre-treated but certainly requires regular applications of biocides and barriers in one form or another throughout the use phase of the window frame, and even this simply slows degradation processes.

Taken in a whole lifecycle context, the wooden window profile receives substantial inputs of biocides, energy and time to keep it functional over a shorter lifecycle than the 30+ years over which my PVC window frames have been in place. My PVC window frames provide efficient insulation, saving energy on heating, have received no inputs of chemicals or energy to keep them functional over that third-of-a-century, and are still going strong.

When they reach the end of their useful life (the metal locking mechanism rather than the PVC gave up the ghost in another of our windows), the PVC element is fully recyclable within a functional British recycling infrastructure.

Looking across the lifecycle, the petrochemical and chlorine inputs have had impact at the point of extraction and vinyl chloride monomer (VCM) is a hazardous substance but is wholly contained in the PVC production process, but inputs beyond that point have been negligible over a long service life after which recycled chemical constituents can have fur ther lives that might span centuries.

Pipe durability in context Now let’s talk about pipes, which I’m sure will be of great interest to readers of this magazine, which includes SAPPMA members.

Our house was built in 1955 with a ductile iron pipe running, we discovered, under our living room. Around a decade ago, the pipe failed and, when exhumed, had almost completely turned into a rusty colander, creating havoc and disruption in its wake! Concrete or even asbestos pipes also have limited lives, and they also poorly resist torsion.

Our failed pipe was replaced with polymer (PE I think but I was not home when it was installed) with an estimated life expectancy of a century, and possibly lasting a whole lot longer.

Protestors might be unhappy that the new water pipe is plastic, but material efficiency over the pipe’s long lifecycle is substantial, beyond which the plastic is recyclable.

This amounts to a very substantial benefit-tocost outcome in material and financial terms over the whole lifecycle of this particular pipe, and potentially also further recycled material lifecycles beyond that. Furthermore, a lot of my work is in south and east Asia, and it was clear after a major earthquake in Nepal that plastic pipes flexed with ground movements while other harder pipe materials fractured. So, there are lifecycle and other technical properties of plastic pipes that simply cannot be matched by many alternatives.

Drilling down into hazard versus risk The above mix of personal narrative versus scientific obser vation builds upon a longstanding case I have been championing as a systems scientist to contest the naïvety within received assumptions as well as myopic regulations, assessment tools and expectations that there are automatically

1

https://fsc.org/en

IMIESA September 2025

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PLASTICS IN PERSPECTIVE

“good” and “bad” materials and constituents.

I said I would get back to hazard versus risk later in this article and here it is: we all know that risk = hazard x exposure, so why is this truism almost wholly lacking in the regulatory environment? VCM is hazardous but, if wholly enclosed in the PVC production process, there is no exposure as none remains in the finished plastic.

Likewise, efficient recycling averts systemic environmental accumulation of constituents beyond product end-of-life. More significantly, we have almost entirely overlooked the benefits that materials serve in terms of meeting our needs safely and efficiently when assessed in risk terms across the whole societal lifecycles of the products into which they are integrated.

The most appropriate material choices and innovations rest not on “good” or “bad” judgments based on oversimplistic hazard criteria in isolation, but through wider consideration of how most appropriately to meet human needs safely and efficiently.

This wider context of the meeting of human needs in the safest and most efficient manner is a vital underpinning of the many pressing sustainability challenges faced today by a world with rising human population and per capita resource demand, dwindling natural resources and a changing climate.

Many will know the “Brundtland definition” of sustainable development – “Development that meets the needs of the present without compromising the ability of future generations to meet their own needs” – to which the global community signed up in 1987 following publication of the report of the World Commission on Environment and Development2.

Recognition of the priority of meeting needs, not merely now but as a bold intergeneration commitment, has little to do with the current focus on hazard alone – judging materials as “good” or “bad”. Nor does the negative focus on hazard chime with the goaloriented emphasis of the 17 UN Sustainable Development Goals3.

Refocusing on the endpoints of meeting the needs of humans and supporting ecosystems reasser ts the aspirational “lost half” of the Brundtland conception of sustainable development that has been serially overlooked in its transposition into legislation, protocols and common understanding4.

This talk of sustainable development goes far beyond altruism.

Wise businesses seek to anticipate emerging markets, as the insuperable forces of environmental change, resource flows and societal tolerances ultimately shape future regulations and market expectations. Pressures driving us to seek a more sustainable future – the climate emergency, the biodiversity crisis, rising concern about pollutant accumulation, issues

orld Commission on Environment and Development. (1987). Our Common Future. Oxford W University Press.

3 United Nations. (2015). Sustainable Development Goals (SDGs). United Nations. [Online.] https://sdgs.un.org/goals, accessed 19th April 2024.

4 Everard, M. and Longhurst, J.W.S. (2018). Reasserting the primacy of human needs to reclaim the 'lost half' of sustainable development. Science of the Total Environment, 621, pp.1243-1254. DOI: https://doi.org/10.1016/j.scitotenv.2017.10.104.

5 Everard, M. (2024). Seeking Sustainable Development on a Level Playing Field: A PVC Case Study. Routledge.

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of distributional and intergenerational equity, and more – are far beyond the conceptual, as they will frame the successful markets of the future that provide optimally safe and efficient means to enable people to meet their needs.

This is why, for example, smoking in public places is banned in many countries, and why arsenic and methyl bromide are no longer permitted for use as insecticides. Tomorrow’s successful businesses will be those shaping their thinking and innovations around optimal ways to enable people to meet their needs in an inevitably different future.

Levelling the playing fields All this and more is expanded substantially in my 2024 book Seeking Sustainable Development on a Level Playing Field: A PVC Case Study5. The case study used in the book is PVC, addressing the “good” and the “bad” in a balanced way, but within the context of risk across the full societal lifecycles of the products into which it is incorporated.

Wider cross-material application of this “level playing field” approach based on common sustainability-relevant criteria reveals that ALL materials used by society in our less than sustainable world have beneficial, problematic, and more or less appropriate aspects at different lifecycle stages, many of them generic to societal resource use habits rather than inherent to the specific substance.

The use of plastics for pipe manufacture to serve a variety of societal needs seems a good option from that perspective albeit, like all materials, with areas for improvement highlighted by “level playing field” analysis!

Reorienting thinking around what materials best help humanity meet its needs safely and efficiently in a changing future is a sound strategy for innovation, choice and future profitability, and one that can (or at least should) better inform the policy environment.

For further discussion you can phone me at +44-7747-120019 or email Mark.Everard@uwe.ac.uk. * Co-Director at Pundamilia Ltd, a visiting Professor at Bournemouth University and Associate Professor at UWE Bristol. He recently presented at the PVC Transformation: Driving Progress in a Changing World conference held during August 2025 in Johannesburg, co-hosted by the Southern African Vinyls Association (SAVA) and the Southern African Plastic Pipe Manufacturers Association (SAPPMA).

ADVICE TO PURCHASER OF PLASTIC PIPING SYSTEMS When procuring plastic piping systems, purchasers are advised to ensure that all products and manufacturers meet the highest quality and compliance standards to ensure the product meets the design life requirements. The following considerations and requirements are recommended and to be stated in any RFQ (request for quotation).

MANUFACTURER TO SUPPLY THE FOLLOWING: • ISO 9001 QMS (Quality Management System) Certificate or Quality Management Plan of the production facility with a copy of the latest Quality Audit Reports to be submitted throughout the supply period • Product Certification (e.g. SANS ISO 4427-2 if HDPE, SANS 966-1 if uPVC, etc.)

• Raw material Certification (e.g. SANS ISO 4427-1 if HDPE) • Certificate of analysis (COA) of polymers used • Certificate of conformance (COC) of products • Undertaking not to use any bought-in recycled material • Laboratory test results, in accordance to the certification bodies’ Specific Permit Conditions (SPC), for each supplied pipe batch shall be submitted • Full traceability of the pipe Batch Number to the raw material used • SAPPMA Membership Certificate with a copy of the latest SAPPMA Audit Reports throughout the supply period

ALL PRODUCTS TO BE INSPECTED ON DELIVERY AND THE FOLLOWING CHECKED FOR COMPLIANCE: • Pipe to be marked in accordance with the relevant standards, with the logo of the certification body and SAPPMA clearly visible.

• Pipe to be inspected for dimensions (OD, wall thickness and ovality) and damage (scratches, gouges, cracks, missing rubbers, etc.)

THE FOLLOWING SHOULD ALSO HAVE AN IMPACT ON YOUR CHOICE OF SUPPLIER: • Is the manufacturer open to unannounced inspections during production?

• Is the quoted price realistic in terms of current polymer prices? (Beware of tenders where the selling price in R/kg is suspiciously low)

THE FOLLOWING BUSINESSES AND INDUSTRIES CAN QUALIFY FOR A SAPPMA MEMBERSHIP: • Pipe & fittings manufacturers • Raw material suppliers

• Consultants • Construction companies

• Municipalities • Water Boards

• Contractors & Installers • Individuals

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PIPE SYSTEMS

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commitment to excellence helps build enduring infrastructure C

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The first use of thermoplastic pipes for municipal water reticulation dates back to the 1930s in Germany. Since then, ongoing adoption has been exponential across all sectors worldwide. IMIESA speaks to Jan Venter, CEO of the Southern African Plastic Pipe Manufacturers Association (SAPPMA) about industr y gains and why plastic pipes are par t of the future.

when a line is started up). These pieces are recycled (mostly on site), and this granular material is allowed to be used in new pipe production. National standards do not allow importing of recycled material for certified pipe. However, it may be used for non-spec pipe in non-critical applications, or to produce other plastic products as part of a circular economy initiative.

What are some of the major milestones in local and international R&D?

What are the key considerations when specifying plastic pipe for sewer systems?

It is a dynamic industry that never stands still.

In recent years there have been significant developments in polymer technology as well as processing equipment. A key innovation is that the design stress of materials has increased considerably over the past 40 years, enabling higher operating pressures and more economical application. This is opening the door for the wider adoption of plastic pipes for bulk water distribution. Furthermore, modern extruders enable very fast line speeds and superior quality control.

As with all other infrastructural installations, only cer tified products conforming to the relevant national standards set by accredited organisations can be used.

Are plastic pipes sustainable?

Indeed. Lifetimes of more than 50 years are expected when installed correctly. Plastic pipes are also environmentally friendly as they require far less energy to produce compared to steel and concrete. Plastic pipes also don’t corrode, which is key in water lines to prevent potential

22 IMIESA September 2025

Is there a clear understanding in industry about the different performance characteristics of PE, HDPE, and PVC? Jan Venter, CEO of the Southern African Plastic Pipe Manufacturers Association (SAPPMA)

potable water contamination. Plus, there is scope for recycling, but within strict parameters.

When is recycling an acceptable practice in pipe manufacturing?

It is inevitable that a small percentage of pipe production will be off spec (particularly

Unfor tunately, there are still degrees of ignorance, but it remains one of the prime focus points of SAPPMA to inform and educate designers and decision makers.

To that end various tools are implemented, such as seminars, formal training courses, our informative website, as well as a comprehensive technical manual (now in its 5th edition). The fact that the latter is issued by an independent and non-profit organisation adds value and credibility.

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What is the current percentage of installed systems for plastic pipe in South Africa versus other materials like concrete, GRP, and steel?

A full-scale independent study has not been done for quite a while. The last such investigation reflected approximately as follows (ref. LHA 2014).

For pressure pipe up to 250 mm diameter, plastic (PVC and HDPE) dominated with an approximate share of 80%. For pipe sizes ranging from 280 to 500 mm, a similar trend was recorded at around 75%. However, steel continued to dominate for pipe diameters of 800 mm and above.

Within the sewer pipe segment, plastic pipes (PVC and HDPE) in a range up to 250 mm achieved a 100% market share, dropping to around 59% for pipes with a diameter of 250 mm or greater.

It is estimated that the percentage of large diameter plastic pipes for sewer and water applications have increased since then.

Furthermore, it must be noted that there are big differences in material properties and hence also in applications.

How can industry specifiers know for certain that they’re buying SAPPMA approved products?

Are SAPPMA members facing cost pressures in terms of polymer prices?

Polymer costs are indeed ver y high.

Interestingly, although a high percentage of our polymers are manufactured in South Africa, they seem to follow a price parity policy in line with global producers in this sector.

So, there’s no local saving.

The best pipe will fail if installed incorrectly. What is SAPPMA doing to promote industry best practice?

A valid statement. SAPPMA endeavours to cover the full spectrum of the industry and hence also the downstream end. We therefore have a division within SAPPMA that focuses on standards and best practices for the installation of pipe systems.

SAPPMA approved products are clearly marked with the SAPPMA logo. In addition, specifiers should request suppliers to provide a valid copy of their SAPPMA membership certificate, which is updated every semester.

What are some of the key issues that SAPPMA would like to see addressed in its sector?

The critical importance of reliable pipeline infrastructure should be better recognised and suppor ted by authorities – local and national. Specifiers and buyers should also refrain from a short-term approach by buying cheaper non-cer tified products that are certain to fail prematurely, with downstream implications in terms of service disruptions and socio-economic impact.

Water and sanitation pipeline systems are long-term investments that are the vital conduits for a healthy and functioning society. We need to look to the future.

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The 1 000 mm PVC-O orientation chamber at Sizabantu Piping Systems’ factory in the RBIDZ. The first 1 000 mm TOM®500 PVC-O pipes were manufactured by Sizabantu Piping Systems in June 2025

CLASSIFICATION – THE HEART OF THERMOPLASTIC PIPES PVC pressure pipes were first used about ninety years ago on the stadium for the Berlin Olympics. PVC-O pipes are about forty years old, during which time they have undergone five iterations of Classification. By Mike Smart, Pr Eng*

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he applicable SANS 16422 Pipes and joints made of oriented unplasticised poly(vinyl chloride) (PVC-O) for the conveyance of water under pressure – Specifications specifies all five Classifications. It is critically important that Classification is not confused with “Class”, the pressure rating (PN) of a pipe.

The strength of the material used to manufacture a pipe determines the Classification, whereas “Class” is the maximum allowable continuous working pressure for the service life of the pipe. The service life of all thermoplastic pipes shall be not less than 50 years at 20⁰C, specified by ISO (International Standards Organisation) protocol, although some thermoplastic pipes provide 100 years’ service life.

The raw material’s Classification is determined by its MRS (Minimum Required Strength) in MPa (Mega Pascals) at 50 years

24 IMIESA September 2025

from the 20⁰C CRRC (Creep Rupture Regression Curve), as shown in Graph 1. Classification is 10 x MRS, and the five Classification iterations of PVC-O are 315, 355, 400, 450 and 500

based on their MRS of 31.5, 35.5, 40, 45 and 50 MPa respectively.

Historically, steel, ductile iron, reinforced concrete, and other “traditional” materials

GRAPH 1: 20⁰C CREEP RUPTURE REGRESSION CURVES

1 000

10 000

100 000

1 000 000 10 000 000

TOM®500: 50 years MRS 55 MPa and 100 years 53.8 MPa

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dominated the large diameter high pressure trunk water main market. However, with recent developments in PVC-O it can now compete in this market with TOM®500 (Tubos Orientado Moleculara Classification 500), the brand name of Sizabantu Piping Systems’ PVC-O Classification 500 PVC-O pipe. Sizabantu Piping Systems has the capacity to manufacture a 1 200 mm diameter PN 25 bar pressure class TOM®500 PVC-O pipe at its factory in RBIDZ (Richards Bay Industrial Development Zone).

The increase in size and pressure class of PVC-O pressure pipes was enabled, inter alia, by improved polymer technology, improved production technology – including in-line orientation and socketing that avoids reheating and repressurising – with variable orientation depending on the location on the pipe.

The development timeline of the manufacturing systems is: - Year 2010: DN 315 PN 12.5 to DN 630 PN 25 – M-OR-P3136 - Year 2013: DN 630 PN 25 to DN 800 PN 20 – M-OR-P3180 - Year 2020: DN 800 PN 20 to DN 1000 PN 16 – M-OR-P3180 - Year 2024: DN 1000 PN16 to DN 1200 PN 25 – M-OR-P5012 - Year 2024: PN TOM®500 PVC-O PN 25 – All diameters The current ISO 16422, single document standard, was converted to a five-part 1, 2, 3, and 5 document, the same format as SANS 4427, in Europe in 2024 promoted primarily by Molecor, Sizabantu Piping Systems’ Spanish technology partners. The ISO 16422 has been voted for adoption by the SABS and will become the applicable standard in the future. It specifies orientation, that determines MRS and thereby Classification, in greater detail.

GRAPH 2:

In Graph 1, the top blue curve for TOM® 500 PVC-O exceeds the required 50 MPa at 50 years (438 300 hours); it is 55 MPa. Furthermore, at 100 years (876 000 hours) its MRS is 53.8 MPa proving its service life exceeds 100 years, which is the service life being demanded by clients and consultants.

This service life is more than twice the ISO protocol requirement. These are exciting developments for the thermoplastic pipe industry, enabling it to compete in the large diameter high pressure pipe market, that was previously beyond its capability and equips Sizabantu Piping Systems to assist in addressing the lack of service delivery problem in South Africa.

Other South African manufacturers are currently preparing to manufacture PVC-O pipes with Classifications that will be different to TOM®500. Therefore, it is critically important that Classification is understood if the correct informed decisions are to be made by clients, consultants and contractors on the use of such pipes.

One of the incorrect decisions being made currently is the SR (Ring Stiffness) of TOM®500 PVC-O pipes when compared to other SANS 16422 Classifications of PVC-O pipes. The Ring Stiffness (SR) of a pipe indicates its ability to withstand external loading without excessive deflection using the formula: SR = E x I / (DN – en)³ where

E = E-modulus I = second moment of inertia DN = pipe nominal diameter En = nominal wall thickness

and: I = L x en³ / 12 where L = unit length of pipe

Therefore, SR is proportional to twice the wall thickness cubed (en³); it has a significant influence on Ring Stiffness. However, SR is also propor tional to the E-modulus, which increases with increased Classification. The increase in the E-modulus of TOM®500 negates the decrease in wall thickness (en) because its MRS is higher than the required 50 MPa at 50 years for a Classification 500 PVC-O pipe, as described in the foregoing.

In Graph 2, the bottom (red dotted) graph is the SR of a PVC-O Classification 500 pipe conforming to SANS 16442. The graph above it (orange dotted) is the SR of a PVC-O Classification 450 pipe conforming to SANS 16422. The graph above that (blue solid) is the SR of TOM®500 PVC-O pipe. And the graph at the top (green dotted), is the SR of a PVC-O Classification 400 pipe conforming to SANS 16422.

It shows the SR graph for TOM®500 PVC-O pipe is above the SR graph for SANS 16422 Classification 450 PVC-O pipe and is close to the SR graph for SANS 16422 Classification 400 PVC-O pipe. SANS 16422, Clause 11.3 “Ring stiffness”, specifies the minimum SR value shall not be less than 4 kN/m², which is approximately the SR of a SANS 16422 Classification 500 PVC-O pipe. However, the SR of a TOM®500 Classification 500 PVC-O pipe is approximately 7 kN/m² showing the increase in its E-modulus negates the reduction in wall thickness.

Conclusion Thermoplastic pipes and piping systems dominate the materials used for services.

They are complex materials which must be understood if correct informed decisions are to be made regarding their design, construction and application. If incorrect decisions are made, there is a loss of confidence in the product, and a loss of market share. Therefore, it is critically important that all stakeholders understand Classification because many additional attributes of TOM®500 PVC-O pipes are superior to SANS 16422 conforming PVC-O pipes. *Owner of Genesis Consulting, a member of SAPPMA, and a specialist consultant for Sizabantu Piping Systems

IMIESA September 2025

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HDPE: THE FUTURE OF CIVIL INFRASTRUCTURE IN SOUTH AFRICA South Africa’s infrastructure is under pressure. Ageing pipelines, increasing urbanisation, and the urgent need for sustainable water management are forcing engineers and municipalities to rethink traditional materials.

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oncrete and steel have long dominated the civils market, but a quiet revolution is underway – driven by high-density polyethylene (HDPE).

HDPE pipes are lightweight, flexible, and incredibly durable. Unlike concrete, they don’t crack under pressure; unlike steel, they don’t corrode. For water, stormwater, sewage, and dam applications, this makes them an obvious choice in environments where reliability isn’t negotiable.

Beyond strength, HDPE suppor ts trenchless installation – a game-changer for projects where disruption must be kept to a minimum.

But perhaps HDPE’s most compelling case is its sustainability. With a design life of more than 50 years, low maintenance requirements, and recyclability, it’s increasingly recognised as the material of choice for future-focused infrastructure projects.

Solfab’s role in the shift Founded in 2008, Solfab has been at the forefront of delivering HDPE solutions for the civils market.

From precision welding to custom fabrications, the company has built a reputation for engineering expertise paired with practical, on-site support.

Its structured and solid wall systems are already transforming water conveyance and stormwater management across the country.

26 IMIESA September 2025

1 As municipalities and contractors search for longterm, cost-effective answers to South Africa’s infrastructure challenges, HDPE stands out – and companies like Solfab are making sure it’s accessible, efficient, and built to last.

For more on how HDPE is reshaping South Africa’s civils sector, visit www.solfab.co.za and explore solutions tailored to your next project.

1 I n Prospecton, Solfab installed a 630 mm sewer pipe along a bridge structure to ensure uninterrupted service, while keeping critical infrastructure safely away from busy traffic routes. This solution balanced technical performance with public safety in a high-congestion zone olfab successfully completed the 2 S installation of 800 mm solid wall bends in Nkandla – a technically demanding project that required precision welding and fabrication.

The custom solution demonstrated the adaptability of HDPE to challenging terrain and unique site conditions 630 mm PN20 water line was 3 A installed beneath Hillcrest’s wetlands using horizontal directional drilling. This trenchless method minimised environmental disruption while ensuring long-term durability and reliability for the community’s water supply

PIPE SYSTEMS

SECURING SOUTH AFRICA’S INFRASTRUCTURE THE THERMOPLASTIC PIPE QUALITY CRISIS South Africa stands at a pivotal moment in the management and expansion of its water and sanitation infrastructure, with the quality of thermoplastic pipes, such as polyvinyl chloride (PVC) and high-density polyethene (HDPE), forming a critical backbone of its networks. Municipal engineers are under significant pressure, facing the dual challenges of maintaining ageing infrastructure and responding to growing demand amid limited budgets. The decisions made today regarding the sourcing, quality assurance, and installation of these pipes will have lasting repercussions for both urban and rural communities across the nation. By Ian Venter

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hermoplastic pipes are not just components – they are essential to the distribution of potable water, the collection and treatment of wastewater, agricultural irrigation, and a swath of industrial applications.

With South Africa producing approximately 150 000 tonnes of thermoplastic pipe annually, translating to nearly 30 000 km of pipeline, the scale of reliance is immense. Yet a crisis looms: the proliferation of substandard pipes threatens the reliability, safety, and sustainability of vital water networks.

The scale and nature of the pipe quality challenge Despite the widespread use and apparent ubiquity of SANS (South African National Standards) markings – such as SANS 791, SANS 967, SANS 966, SANS ISO 16422, SANS 4427-2, and SANS ISO 21138 – on pipes throughout South Africa, these numbers do not always guarantee actual compliance with the standards.

Industr y audits and investigations have revealed that, in some cases, products marked as compliant are found to fall short on laboratory testing or long-term performance.

The misperception that SANS markings equate to verified compliance has become a significant concern for engineers, municipal procurement officers, and the general public.

28 IMIESA September 2025

The financial ramifications of using substandard pipes are substantial. Each year, municipalities and utilities bear the costs of frequent repairs, water loss, and emergency replacements. Environmental consequences also emerge, with leaking pipelines exacerbating water scarcity, erosion, and pollution. Perhaps most insidious is the erosion of public trust in infrastructure, as repeated failures undermine citizens’ confidence in the services that underpin their daily lives.

The compliance divide: Beyond SANS markings A critical misconception persists in the field: the belief that a pipe bearing a SANS number is, by default, fully compliant and fit for use. In reality, compliance is a multifaceted process that involves not only initial laboratory testing but also ongoing audits, documentation, and adherence to international best practices.

Many manufacturers operate internal laboratories to test PVC and HDPE pipes; however, these in-house facilities frequently lack ISO 17025 accreditation, which is the international gold standard for laboratory competence. ISO 17025 accreditation ensures that laboratories can accurately measure errors and uncertainties, maintain suitable environmental controls (such as

PIPE SYSTEMS

ABOUT THE AUTHOR Ian Venter is a consultant specialising in polymer piping systems, representing Polymers and Piping (fittings) Systems South Africa (PPfSSA). With extensive experience in quality assurance and industry collaboration, Ian is dedicated to advancing standards and promoting compliance throughout the pipe manufacturing supply chain.

For further information, phone +27 82 770 8244 or e-mail: IanVenter@PPfSSA.com.

temperature during testing), and utilise properly calibrated equipment. Without these safeguards, test results may be unreliable, and non-conforming products may reach the market.

Compliant manufacturers recognise the limitations of in-house testing and routinely validate their results against those from independent, ISO 17025-accredited laboratories. Non-compliant manufacturers may skip this step, relying instead on unverified or incomplete test data, which increases the risk of systemic product failures.

Common technical failures in non-compliant testing Audits of thermoplastic pipe manufacturers have revealed a variety of recurring technical failures. For instance, proper hydrostatic testing is critical to confirming a pipe’s longterm pressure resistance. However, common failures include not submerging specimens as required, using water with an unregulated temperature, or failing to purge air from the system – all stipulated in SANS 4427-2.

Dimensional non-conformance presents another issue: even minor deviations in wall thickness, sometimes as small as 1 mm, can significantly reduce a pipe’s pressure rating and ser vice life, and regular dimensional checks are often inadequately performed or documented. Material property negligence is also prevalent, as specific tests – such as those for long-term thermal stability, thermal reversion, and PVC gelation – are either not appropriately conducted or are skipped altogether, leaving the very factors that affect pipe longevity unverified.

Additionally, poor record-keeping, including the use of handwritten logs rather than electronic, auditable records, can make

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it challenging to trace quality failures or establish accountability after an incident, posing a systemic risk to the entire supply chain. These technical failures do not merely exist on paper; they manifest as realworld problems, including premature pipe failure, escalated water loss, environmental degradation, and significant repair costs.

Legal, financial, and liability risks The selection and approval of pipes based solely on manufacturer certificates, without independent verification, expose engineers and municipalities to substantial legal and professional risks. When pipe networks fail and forensic investigations are conducted, scrutiny often focuses on the approval process. Acceptance of unverified test results is increasingly interpreted as a lapse in professional duty or even negligence.

Liability may extend to the engineers involved, procurement officials, and their organisations. This risk encompasses court proceedings, professional disciplinary action, and loss of insurance coverage.

In some cases, those responsible for specifying and approving the use of noncompliant pipes can be held personally liable for damages, including the costs associated with environmental cleanup, replacement infrastructure, and injury claims.

To mitigate these risks, engineers and procurement officers must ensure that all compliance documentation is thorough, up-to-date, and independently verified.

Cer tificates from South African National Accreditation System (SANAS)-accredited bodies – such as SATAS, SABS, SABPS, AENOR, or SAPPMA1 – should be supported by a complete paper trail of laborator y results, raw data, and on-site audits.

Certification bodies: Their role and limitations Cer tification bodies play a central role in auditing and cer tifying manufacturers of thermoplastic pipes. Their audits are essential for ensuring that manufacturers adhere to national and international standards, providing an independent verification of the compliance claims made by manufacturers.

Certification is a powerful tool in theory, but in practice its effectiveness depends not only

I t is noted that these bodies play a vital role in upholding standards; this guidance is intended to support the robustness of the entire ecosystem.

IMIESA September 2025

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on the rigour of the audit process but also on the commitment of manufacturers to quality at every level of their operation.

However, the process is not without its limitations. Actual, sustained compliance relies on a culture of internal discipline and responsibility within manufacturing organisations. Certification ideally serves as an indicator that material verification, process control, and a deeply rooted quality ethos are present throughout every phase of production and documentation.

Yet, if audits are treated merely as procedural hurdles to be cleared, or if the primar y aim becomes passing a narrowly defined set of tests rather than fostering real, systemic improvement, then the actual value of certification is greatly diminished.

Additional challenges complicate this landscape. The high cost and resource

demand of thorough, frequent audits can be a significant barrier, particularly for smaller or emerging manufacturers. There is also a risk in the industry’s potential overreliance on third-party data and documentation, which, if not carefully validated and cross-checked, may be susceptible to manipulation or misrepresentation.

Genuine confidence in product reliability is only possible when certification is seen not as a formality, but as a reflection of an ongoing, organisation-wide commitment to best practices and continuous improvement.

In cultivating this quality-driven environment, all stakeholders must remain vigilant and proactive, ensuring that certification stands for real-world reliability – not just a “tick box” exercise.

Practical guidance for stakeholders To address the challenge of non-compliance and improve public confidence, stakeholders – including engineers, procurement officials, and contractors – must adopt rigorous, evidencebased practices. Key recommendations include mandating auditor testimony and ensuring that raw production and testing data are accessible for independent review.

Stakeholders should require verifiable material genealogy, tracing the origin of materials from polymer reactors through to finished pipes, with all steps verified by SANAS-accredited bodies. It is essential to enforce unannounced audits through appropriate contract clauses, with decertification as a consequence of noncompliance.

Adopting lifecycle costing is critical, considering not just the upfront cost of pipes but also their likely long-term performance, and using historical failure data to penalise bids from suppliers with poor track records.

30 IMIESA September 2025

Scrutinising bidders is necessary, requesting real-time audit reports and proof of prior unannounced audits before awarding contracts. Comprehensive pre-qualification dossiers should be required, providing complete audit records, material certificates, and lab correlation data, all of which must be transparent and auditable.

The establishment of a dynamic denylisting process is essential: suppliers and certifiers found to be non-compliant should be excluded, with regular review and transparency. On-site validation is a practical step, where contractors should physically inspect wall thickness, verify resin batches, and refuse installation where documentation is insufficient. Finally, any delivery failing to meet standards should be reported to SANAS, the client, and relevant stakeholders, ensuring accountability and the creation of a public record.

The cost and consequences of inaction Failing to address the quality of thermoplastic pipes can have widespread and lasting consequences. From a financial perspective, the cost of replacing faulty pipes can be ten to twenty times the original investment, especially when failures cause collateral damage such as road collapse or contamination.

Water security also suffers: according to some estimates, up to 40% of treated water in South Africa is lost through leaks, many of which can be traced to substandard pipes.

Liability risks not only increase for professionals and organisations but also for communities, who may suffer from service interruptions, waterborne diseases, and environmental harm. At an economic level, non-compliant manufacturers distort markets by undercutting prices, which reduces incentives for innovation and continuous improvement.

Case study: A preventable municipal failure A poignant example involves a municipality that installed 5 km of SANS 4427-2 HDPE pipe from a supplier where certification and traceability documentation were later found to be incomplete. Within a few years, catastrophic failures were observed, resulting in severe water loss and the formation of sinkholes that threatened nearby infrastructure. The cost of remediation exceeded R15 million, dwarfing the original project budget.

Forensic analysis revealed that the resin used in the pipes had been adulterated

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and that critical traceability and validation procedures had been neglected. The specifying engineer faced charges of professional misconduct for failing to address these requirements and for relying solely on unverified manufacturer documentation.

Root causes and the path forward Several root causes underlie the current crisis. Insufficient enforcement remains a significant issue; although standards exist, enforcement at both the procurement and installation stages are often inconsistent, which allows non-compliant products to enter the market.

Economic pressures fur ther complicate matters, as tight municipal budgets incentivise the selection of lower-cost products, even when there are doubts regarding their quality. Awareness gaps persist, since not all stakeholders fully understand the nuances of cer tification, accreditation, and compliance, leading to misplaced trust in markings and certificates.

Oversight is fragmented, with multiple agencies and bodies involved in standards

setting and enforcement, which can sometimes result in gaps or overlaps in responsibility.

Moving forward, a coordinated national effort is needed to align manufacturers, cer tification bodies, engineers, and government regulators in pursuit of higher standards and greater transparency. This will require investment in personnel training, technology for traceability and auditing, as well as the development of clear, enforceable protocols for verification and accountability.

Conclusion: Engineering leadership for sustainable infrastructure While established certification bodies and industry associations have made significant efforts to improve standards, the persistence

of non-compliance demonstrates that policies alone are not enough. South Africa’s future water security, economic resilience, and public health require renewed commitment from all stakeholders to prioritise forensic proof, access to raw data, and the adoption of unannounced inspections as the norm.

This is more than a technical or administrative challenge – it is an ethical imperative. Engineers, manufacturers, and policymakers must collaborate to ensure that short-term cost savings do not compromise long-term reliability and safety.

By adopting evidence-based practices, enforcing rigorous standards, and fostering a culture of transparency and accountability, South Africa can safeguard the integrity of its infrastructure for generations to come.

DISCLAIMER This document is intended for educational and professional discussion purposes. The views expressed are based on industry observations and do not imply wrongdoing by any specific entity. Readers are encouraged to verify claims through independent sources.

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RAILWAY ENGINEERING

SHIFTING FROM ROAD TO RAIL

WALVIS BAY TO KRANZBERG LINE UPGRADE ENHANCES SADC LINKS Working under live rail conditions, track upgrades were confined to six-hour possession windows, requiring tight scheduling, daily reinstatement of track, and high-precision techniques for welding and alignment

A section of the Walvis Bay to Kranzberg line, which traverses a varied terrain of harsh desert, cliffs and coastal zones

Completed at the end of 2023, the Walvis Bay to Kranzberg Railway Upgrade Project represents a transformative engineering initiative under the Namibia Transpor t Infrastructure Improvement Project (NTIIP), co-financed by the African Development Bank (AfDB) at a total cost of around N$3,4 billion.

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trategically located in Namibia’s Erongo Region, this 220 km rail upgrade was identified as a national priority aimed at revitalising the backbone of Namibia’s rail transpor t sector. The ultimate goal is to support regional economic integration, improve logistics efficiencies, and enable a more competitive freight and passenger rail service across the Southern African Development Community (SADC) corridor.

This has been achieved by increasing the railway line’s axle load capacity from 16.5 to 18.5 tonnes per axle (TAL), thereby enabling operational speeds of up to 80 km/h for freight and 100 km/h for passenger trains.

In addition to enhancing both safety and per formance, the new line also facilitates the shift from road to rail for long-haul freight.

This suppor ts the green transpor t goals outlined in Namibia’s national development strategy – reducing congestion and road infrastructure deterioration within a unique ecological landscape that includes the Dorob National Park.

To complete the works, Bigen Kuumba Infrastructure Ser vices was appointed by

32 IMIESA September 2025

Namibia’s Ministry of Works and Transport to lead the professional team, provide project management, conduct technical investigations, and oversee design and construction monitoring.

In turn, Bigen Africa – Bigen Kuumba’s holding company – was responsible for the engineering design, as well as procurement in terms of its EPCM agreement.

The detailed feasibility study conducted included dynamic simulations over a 10-15 year horizon to test various key elements that included rail lengths, axle loads, speeds, and signalling configurations.

The project was structured across three major implementation packages, comprising the Goods Package (including the supply of 20 000 tonnes of 48 kg/m rails in 36 m lengths, and 53 turnouts in either left or righthand configuration); Works Package C001 for the 115 km Walvis Bay to Arandis section (completed in April 2023); and Works Package C002 for the remaining 111 km from Arandis to Kranzberg (completed in November 2023).

The contractors for each package, respectively, were CCCC-Profile Joint Venture, China Gezhouba Group Company Ltd, and the CNQCUnik Joint Venture.

Working under live conditions The Walvis Bay to Kranzberg Railway Upgrade Project stands out as a hallmark of engineering precision and quality assurance, underpinned by a comprehensive and independently monitored Quality Management System (QMS).

In addition to the harsh desert conditions – with its sporadic sandstorms – all work needed to be carried out under live conditions in terms of rails, sleepers, turnouts, and ballast installations. Work was confined to six-hour possession windows, requiring tight scheduling, ï daily reinstatement of track, and high-precision techniques for welding and alignment.

Alongside exact logistical planning, this meant that a rigorous health and safety programme was an overriding requirement. Plus, every project phase had to be completed with 100% precision the first time around across multiple fronts.

This put the team to the test, and in response a series of key innovations where introduced.

These include: • B ypass lines: Temporar y bypass lines were designed and constructed to enable uninterrupted live rail operations during construction, increasing working windows and reducing idle time.

RAILWAY ENGINEERING

• Sand mitigation measures: Customised sand retention berms were engineered near Swakopmund (forming part of the rail link) to prevent wind-blown sand from infiltrating the ballast, significantly reducing contamination in a dynamic dune environment.

• M aterial reuse technique: Formation strengthening techniques reused existing ballast blended into the sub-base to meet G4–G5 performance standards, reducing material import needs, lowering costs, and limiting environmental impact.

• Corrosion-resistant infrastructure: Sleeper shoulders for turnouts were galvanised beyond scope to withstand coastal corrosion within 10 km of the ocean, enhancing durability.

• Mid-project design adaptation: Mainline turnout designs were upgraded from 1:9 to 1:12 mid-project to accommodate operational flexibility with minimal construction impact.

• Rail logistics innovation: A decentralised rail delivery model utilised three laydown areas and bolster wagons, enabling delivery rates of up to 99 rails/day – well above the planned 59/day target.

• COVID-19 response strategy: The project maintained momentum during the pandemic through dynamic health protocols, essential ser vices permits, staggered workforce mobilisation, and agile planning, ensuring delivery milestones were met with strong HSE compliance.

• Subcontractor resource strategy: A multi-tier subcontractor model effectively addressed plant and labour constraints, achieving 95% local employment and extensive skills transfer, suppor ting long-term regional development.

Civil and earthworks designs were developed using the COLTO 1998 specifications, Track and plate laying designs adhered to Transnet’s E.10 Engineering Specifications, which were locally adapted for TransNamib operational requirements

A decentralised rail delivery model utilised three laydown areas and bolster wagons, enabling delivery rates of up to 99 rails/ day – well above the planned 59/day target

ensuring compatibility with regional transport infrastructure standards.

Track and plate laying designs adhered to Transnet’s E.10 Engineering Specifications, which were locally adapted for TransNamib operational requirements. Upgrading the track’s axle load capacity required extensive formation strengthening and widening, The project scope also included refurbishment and strengthening of 13 bridges – including four major structures – and the installation of new 1:12 turnouts and truss/girder bridge decks under five-day shutdown windows in accordance with COLTO and SANS 1200 specifications.

girder and truss forms that present a clean, balanced silhouette across the terrain.

Trackside furniture, including kilometre markers, gradient indicators, clearance gauges, and speed boards, were also manufactured and installed using uniform dimensions and materials, typically in neutral tones to minimise their visual intrusion.

Additionally, where possible, recycled materials such as offcut rails from old installations were repurposed creatively for items like clearance markers and fencing. This approach not only promoted sustainability but also lent a subtle authenticity and continuity to the railway’s historical identity.

Contractor design participation While much of the base design was consultantled, provision was made for contractor-led design responsibilities in select areas, particularly around bypass lines, site access arrangements, construction methods, and value engineering options (e.g. strengthening versus replacement). This flexible model allowed the respective contractors to submit method statements, design amendments, and bypass track plans for Engineer review and approval, ensuring continual optimisation during execution. In executing the various works, each contractor was required to submit a comprehensive Project Management Plan.

Aesthetic bridge and track integration In refurbishing the bridges, key consideration was given to their environmental and aesthetic impact to blend in with the pristine desert landscape.

In response, strategic river crossings, such as those at Swakopmund and Khan River, were designed or rehabilitated using symmetrical

Conclusion The long-term regional impact of the project is profound. By improving travel times along the corridor by 25%, and upgrading the railway to accommodate heavier, longer trains, the project has boosted freight reliability and regional trade.

This improved connectivity is catalysing economic activity in rural areas, creating market access for local businesses, and encouraging new investment in sectors such as mining, logistics, and tourism.

Ultimately, the project has not only redefined Namibia’s transport landscape; it has delivered enduring social value that uplifts communities and builds resilience across generations.

This philosophy aligns with Bigen’s own ethos of “doing good while doing business”. A proud testimony to this was recognised in August at the CESA Aon Engineering Excellence Awards 2025 where Bigen won the Best International Project category for the Walvis Bay to Kranzberg Railway Upgrade Project.

IMIESA September 2025

33

RENEWABLE ENERGY & ELECTRIFICATION

PROTECTING BUILDINGS’ EMBODIED CARBON WITH RETROFITTED SYSTEMS In a statement, now almost three years old, the World Economic Forum (WEF) said around 80% of the buildings in existence will still be around in 2050; it is therefore essential that in order to combat climate change we retrofit them for energy efficiency. By Thabang Byl*

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dditionally, a study undertaken

by Schneider Electric and WSP in 2023 indicated that retrofitting buildings with digital and electric solutions can significantly reduce carbon emissions, with potential reductions of up to 70%. This involves integrating smart building and power management systems, as well as replacing fossil fuel-based heating with electric alternatives.

Fast-forward to 2025, and both the statements still hold true. Indeed, they have become guiding principles in conversations around sustainability, urban planning and energy efficiency.

In South Africa, where many commercial buildings, particularly in cities like Pretoria, Johannesburg, and Cape Town date back to the 1970s, 1980s or even older, retrofitting should enjoy priority. These ageing structures, often home to government offices or long-term tenants, are increasingly falling short of today’s demands for comfort, energy performance, and environmental accountability.

Furthermore, the idea that mostly well-built and completely habitable buildings are simply demolished is neither feasible nor financially viable. The greener and downright prudent alternative therefore lies in retrofitting; equipping these buildings with modern technologies that reduce energy consumption, improve tenant satisfaction, and future-proof these assets against rising utility costs and stricter carbon regulations.

34 IMIESA September 2025

But why so modern?

Today, older buildings mostly feature inefficient HVAC systems, poor insulation, and outdated lighting and metering infrastructure. As a result, building owners are left managing complaints around inconsistent temperatures, high operational costs, and growing vacancy rates.

“Thermal comfort” becomes a luxury instead of a standard, and tenants grow increasingly dissatisfied with spaces that are no longer fit for purpose.

This is where smart Building Management Systems (BMS) and integrated energy platforms come into play. These systems offer centralised, data-driven control over HVAC, lighting, and energy monitoring, enabling real-time decisionmaking and predictive maintenance.

A major plus is that these retrofits don’t require tearing down concrete or rebuilding from scratch.

As mentioned, many older buildings still have structurally sound foundations and facades.

Preserving them means maintaining what is known as embodied carbon, the emissions produced during the original construction.

Retrofitting also has multiple advantages beyond mere energy savings. It allows landlords, operators and owners to: • Reduce energy waste by installing unified HVAC and lighting systems.

• Support predictive maintenance to lower longterm operational costs.

• Ensure better air quality, especially in shared environments like hospitals or public offices.

• Achieve green certifications through accurate digital monitoring.

Tenant retention and value A modernised building is not just more efficient, it’s more attractive. Energy-conscious tenants are increasingly drawn to spaces that align with their sustainability goals. Imagine walking into a reception with a Green Building Council certification – this immediately signals environmental credibility, which can influence leasing decisions and investor interest.

Retrofitting also improves tenant retention.

When facilities are comfortable, costs are predictable, and systems are reliable, people are more likely to stay. This long-term occupancy protects the asset’s value and enhances return on investment for property owners.

A response to unreliable supply and climate change South Africa’s unstable energy landscape adds urgency to this transformation. With unplanned outages and load shedding a persistent reality, integrating renewables and improving building efficiency can significantly lessen pressure on the national grid and provide consistent supply to tenants.

Retrofitted buildings that include solar panels, smart energy storage, and real-time monitoring can also contribute to a more stable and resilient national energy mix.

Importantly, South Africa’s energy transition and climate commitments hinge on sectors like commercial real estate playing their part.

Buildings worldwide are among the largest consumer of energy, so retrofitting them is one of the quickest ways to drive down emissions without incurring the high environmental and financial costs of new construction. *Buildings Segment Lead at Schneider Electric

Flygt 2450

Redefined. Reimagined. Reinforced.

The Flygt 2450 is the industry’s first - and only - fully submersible dewatering pump to reach 300m of shutoff head. Built on the Flygt 2400 series’ more than 40-year legacy of reliability, the 2450 is ideal for heavy infrastructure construction and underground mining applications, this single powerhouse pump reduces the need for additional equipment, reducing lifecycle costs.

A force to be reckoned with

Designed with a Hard-Iron™ impeller for superior wear resistance, the Flygt 2450 handles dirty water with up to 70% hydraulic efficiency, eliminating premature failures and expensive repairs from harsh conditions.

Reclaim uptime

Designed for up to 6,000 hours between servicing for less frequent and more affordable maintenance, the 2450 enables significant cost and resource savings, while improving safety for personnel. A six-bolt hydraulic access further reduces required service time with hydraulic end disassembly possible in only 15 minutes.

xylem.com

WATER & WASTEWATER Water is one of the most precious resources on Earth, yet it is often wasted in our own homes. Household leaks such as dripping taps, leaking toilets, or faulty pipes are some of the biggest contributors to unnecessary water loss.

EASY GUIDE TO FIXING LEAKS AT HOME

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single dripping tap can waste between 30 and 60 litres of water a day, and when multiplied across thousands of homes in South Africa, the impact is staggering. These small, unnoticed leaks add up to millions of litres of clean water lost.

To help households reduce waste and lower water bills, Water Wise provides simple, do-it-yourself (DIY) solutions to identify and fix leaks before they become costly problems.

HOW TO REPLACE A TAP WASHER AND SAVE ON YOUR MUNICIPAL WATER BILL Taps may differ in design, so use this guide as a reference if your tap mechanism looks slightly different. If you are uncertain, it’s best to seek assistance from a registered plumber.

STEP 1: Locate the basin shut off valve, usually on the wall behind the basin, and turn off the water

STEP 2: Remove the screw cover from

STEP 3: Use an Allen hex key or a

STEP 4: Unscrew and remove the valve

STEP 5: Use a spanner to loosen the

STEP 6: Unscrew the valve from the tap

STEP 7: Use a screwdriver to loosen the

STEP 8: Remove the old nylon washer

screwdriver to remove the handle

cover from the tap

old nylon washer at the bottom of the valve

STEP 10: Congratulations. You are now Water Wise.

STEP 9: Insert a new nylon washer onto the valve and replace the tap in reverse order from Steps 6 to 1

36 IMIESA September 2025

www.randwater.co.za 0860 10 10 60

the tap

valve

from the valve

WATER & WASTEWATER

BWUA demonstrates visionary leadership in ISO compliance The Badirammogo Water User Association (BWUA), formerly known as Lebalelo, has successfully completed an independent external second-party audit confirming compliance with the minimum requirements of three additional ISO standards, namely ISO 50001:2018 (Energy Management), ISO 55001:2024 (Asset Management) and ISO 37101:2022+A1:2024 (Sustainable Development in Communities).

T

hese achievements build on BWUA’s NOSA 5-Star Platinum Grading (CMB253), attained in December 2024, and existing certifications to ISO 9001:2015 (Quality Management), ISO 14001:2015 (Environmental Management) and ISO 45001:2018 (Occupational Health and Safety).

This brings the Association’s total to seven recognised standards, a distinction that places BWUA among a rare group of organisations, and possibly the only one in its sector, to maintain six ISO standards alongside the NOSA Integrated Five Star System. Together, these seven standards demonstrate BWUA’s integrated approach to quality, safety, environmental stewardship, energy efficiency, asset management and community sustainability.

Measurable gains In terms of ISO 50001:2018 (Energy Management) compliance, the audit confirmed BWUA’s strong progress in monitoring electricity usage, resetting pumps to operate outside Eskom peak times, phasing out unused chemicals and transitioning to solar energy solutions. Early tracking has already shown reduced diesel consumption, and clear objectives are in place to continue driving down usage.

For ISO 55001:2024 (Asset Management), the auditors confirmed significant advances

in asset tracking, from acquisition through to operational use. Developments include tagging and QR coding for all assets, from pumps to specialised equipment, using the SafetyCulture digital application to store inspection data and ensure that every asset is monitored, maintained and traceable.

The rare ISO 37101:2022+A1:2024 (Sustainable Development in Communities) standard, which focuses on enhancing community quality of life, resilience and sustainability, was another area of success.

BWUA achieved a level 3 maturity rating in its first-time assessment. The auditors praised BWUA’s school upgrade programme, noting its engagement with Traditional Authorities, School Governing Bodies and other key stakeholders to ensure sustainable, longterm benefits. They also recognised the indirect impact of BWUA’s work, such as creating healthier environments for teachers and learners.

Dr Kobus Duvenhage, BWUA’s Chief Executive Officer

HSE Function) for the Northern Region. These accolades acknowledge the Association’s building of a safety-first culture and the embedding of international best practice across the organisation.

Comments Dr Duvenhage: “To achieve compliance with three additional ISO standards, on top of our existing certifications and NOSA grading, is an extraordinar y accomplishment. It demonstrates to our stakeholders, including funders and communities, that BWUA operates to worldclass standards in every key area of our work.

This gives us the credibility and operational resilience to deliver on our purpose of improving lives through water.”

An internal perspective of the Spitskop pump station

NOSA Northern Region Award The strength of BWUA’s systems was fur ther recognised in July 2025 when the Association won the NOSA Northern Region Award for Best Integrated Five Star System in the Electricity, Gas and Water Supply sector for the second consecutive year. In the same month, BWUA’s Chief Executive Officer, Dr Kobus Duvenhage, was named Managing Director of the Year (Full-Time

The Havercroft storage dams and pump station, which are owned, operated and maintained by BWUA

BWUA’s Spitskop storage dam and pump stations facility

IMIESA September 2025

37

PUMPS

New wastewater pump for local municipalities and industries “The pumps are matched to IE5 class motors to further improve efficiency, and a range of smar t features allows users to run the pump correctly for different conditions. It monitors its condition in realtime, automatically detecting blockages, engaging in deragging routines, and adjusting its operating point to match system demands, which is a feature that significantly reduces wear and the need for unscheduled maintenance.

“With the Amarex Pro, clients can expect far fewer breakdowns. Its automatic clog detection and soft start technology reduces stress on the system, and integrated motor and vibration protection gives operators full confidence in continuous operations.”

Plug and play simplicity

The latest wastewater pump from KSB Pumps and Valves is making waves in the industry due to a host of new features that provide users with an ultra-durable long service pump with fewer blockages and lower maintenance requirements than traditional pumps.

I

t comes at a challenging time for municipalities and industrial pump users as aging infrastructure fails and maintenance requirements for older pumps is becoming increasingly demanding.

Now, the KSB Amarex Pro submersible pump provides solutions to solve many of the challenges now and in the future.

According to KSB Pumps and Valves wastewater market area manager, Hugo du Plessis, the new series is “a game changer for municipal and industrial pump stations alike”. They are built for reliability and ease of use with the combination of technologically advanced hydraulic design and advanced smar t capabilities for improved management.

“At the core is the open dual vane D max impeller for improved hydraulic efficiency and unsurpassed energy savings, particularly in heavy-duty abrasive or aggressive wastewater environments,” du Plessis explains.

38 IMIESA September 2025

The KSB Amarex Pro submersible pump

Du Plessis adds that one of the pump’s best features is its plug and play simplicity. Each unit is preset to the client's specified duty point, requiring little more than connection to KSB’s free Ser viceTool to fine-tune per formance.

The customer inter face is ver y intuitive, making commissioning and configuration straightfor ward even in remote sites.

The range is also designed to fulfil multiple roles with its “adaptive operating point” flexibility, which covers two to three duty sizes with a single pump. This translates to fewer product variants and reduces spare parts stock in the field.

Its toughness and low maintenance manufacture are also impressive with each pump supplied with a hard iron (G2) impeller and a choice of mechanical seals tailored to cope with abrasive sludges and aggressive wastewater. A range of adapter claws and an easy to navigate “GoToAmarex” app also ensures upgrades to existing installations are seamless and fast.

“KSB’s mission is to deliver solutions that save both energy and operational hassle. The Amarex Pro is a great example of this, being smar t, efficient and reliable. It’s precisely what South Africa’s pump station operators need,” du Plessis concludes.

88 IMESA TH

CONFERENCE

BOOK YOUR accommodation NOW CONFERENCE VENUE EAST LONDON ICC 22 Esplanade, Quigney, East London Premier Hotel ELICC – onsite BOOKING CODE : IMESA2025

HOTELS ONSITE OR WITHIN CLOSE PROXIMITY OF THE EAST LONDON ICC (IMESA will provide transport to and from the hotels listed below)

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CONFERENCE ENDORSED BY

t: +27 (031)266 3263 e: conference@imesa.org.za marketing@imesa.org.za www.imesa.org.za

IMESA ORGANISER

THE INSTITUTE OF MUNICIPAL ENGINEERING OF SOUTHERN AFRICA (IMESA)

VEHICLES & EQUIPMENT From left: Lizarox director, Michael Crackett and Astec Industries regional sales manager, Casper Booyse

closed side setting (CSS) adjustment; interchangeable chamber configurations; field-replaceable base frame tub and V-seat liners; and a hydraulic cone brake. This unit is permanently precision balanced with protected internal counterweights. Its feed hopper features a level sensor, and it has a 95 litre lube oil tank with an immersion heater.

Expanding fleet

Powerful crushing performance on Limpopo road project An Astec FT200DF mobile cone crusher is delivering a powerful, efficient crushing performance on site at the South African National Roads Agency’s (SANRAL’s) construction project between Bela Bela and Modimolle in Limpopo.

T

his versatile, durable machine was supplied by Astec Industries to longstanding customer Lizarox. It is the most recent Astec unit ordered by Lizarox and is proving its mettle on the company’s contract that forms part of the SANRAL project to rehabilitate a 26.8 km stretch of the R101 national road.

Astec Industries regional sales manager, Casper Booyse, notes that the FT200DF is purpose-built for productivity in the toughest field conditions. Its mobility and fast setup mean that the crusher is ready to perform from day one.

“Equipped with the proven Kodiak K200+ cone crusher, this machine offers up to 400 tph of production capacity. Its roller-bearing design

reduces operating costs by up to 50%, while improving energy efficiency,” Booyse explains.

“This unit is your go-to for reliable secondary and tertiary crushing on the go. From remote locations to high-production environments, the FT200DF offers unmatched durability for demanding conditions and a high-quality end product,” he expands.

“Backed by Astec Industries’ full aftersales support – including spares, technical service and expert advice – this unit is more than just a crusher, it’s a long-term performance partner.”

Integrated features The FT200DF’s other notable features include a variable-speed hydraulic drive; remote

The Astec FT200DF is permanently precision balanced with protected internal counterweights

40 IMIESA September 2025

This is the latest in a series of Astec machines chosen by Lizarox. In 2023, the first Astec mobile track unit supplied in South Africa – an Astec GT205 three-deck mobile screen – was successfully commissioned

by Astec Industries for Lizarox. Prior to that, a mobile jaw and cone crusher had been supplied.

Lizarox director Michael Crackett says that Astec Industries’ long-standing relationship with Lizarox is founded on consistently reliable products and ser vice. “Astec’s backup on our equipment has always been excellent. When faced with challenges in the past, they always stepped up to the plate.

This remains the case today and provides us with a sense of comfort that we are in good hands when it comes to product reliability and backup ser vice. We are excited about Astec Industries’ range of products and hope to continue to expand our current plant mix with more Astec products.”

Adds Booyse: “We are delighted to add this Astec FT200DF mobile cone crusher to our long par tnership with Lizarox, a solutions-oriented company with a wealth of knowledge. We look for ward to continuing to par tner with them, and helping them to attain profitable production goals, valued benefits and deliver a competitive advantage to their clients through our innovative, worldclass equipment.”

Equipped with the proven Kodiak K200+ cone crusher, the Astec FT200DF offers up to 400 tph of production capacity

VEHICLES & EQUIPMENT

CHURCH RELOCATION COMPLETED IN ONE PIECE The route was carefully analysed and prepared, including temporary road widening and compacting work

The 713 tonne Kiruna Church in transit

civils works and conducted road tests using SelfPropelled Modular Transporters (SPMTs) loaded with counterweights to simulate the church’s axle load.

M

ammoet recently completed the successful relocation of the iconic Kiruna Church, one of Sweden’s most treasured architectural landmarks. The operation, which took place over two days during August 2025, marks a historic moment for the town of Kiruna and showcases the power of precision engineering and collaboration.

Built in the early 20th century and once voted Sweden’s most beautiful building, Kiruna Church is also one of the country’s largest wooden structures. Its relocation became necessary due to the expansion of LKAB’s Kiruna mine, which required several buildings to be moved to a newly developed city centre 5 km away.

Project execution Commissioned by civil engineering firm Veidekke and LKAB, Mammoet was entrusted with transporting the 713 tonne church in one piece – a task that demanded over 1 000 hours of meticulous planning. The move, dubbed “The Great Church Walk, drew thousands of spectators, including the King of Sweden, and was carried out with exceptional care to preserve the integrity of the fragile structure.

To ensure the church’s safety, Mammoet worked closely with Veidekke and Swedish wood engineering specialists to model and test the building’s response to lifting and transport.

The route was also carefully analysed and prepared, including temporary road widening and compacting work. Mammoet advised on these

With the methodology approved, the church was jacked up to a height of 1.3 m and placed on steel beams supported by two trains of 28 axle lines of SPMTs. A custom monitoring system developed in-house ensured the structure remained stable throughout the journey, allowing for a maximum tilt of just 7.5 cm between sides.

The relocation took place during daylight hours, with the church arriving safely at its new location.

Once in place, the SPMTs lowered the structure onto its new concrete foundations, completing a move that will be remembered for generations.

In an allied move, Mammoet was also responsible for relocating the church’s 90 tonne belfr y using a different SPMT configuration, fur ther contributing to the preser vation of Kiruna’s cultural heritage.

CEMENT & CONCRETE

Recent tests were initiated by a public sector power station owner and operator to determine whether concrete treated with SCP P3 Industrial met its strict concrete durability requirements

COLLOIDAL SILICA MAKES DURABLE CONCRETE EVEN MORE DURABLE Innovative SprayLock Concrete Protection (SCP) technology provides a reliable and quantifiable improvement in the ser vice life and structural integrity of concrete infrastructure, according to the latest tests under taken by an independent South Africa laborator y.

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hese fur ther corroborate the findings of earlier laboratory tests that post-set applied colloidal silica significantly deaccelerates the rate of chloride through concrete. Furthermore, more than 100 research papers authored by over 15 research teams have documented the improved properties of concrete containing colloidal silica.

The recent tests were initiated by a public infrastructure owner and operator to determine whether concrete treated with SCP P3 Industrial met its strict concrete durability requirements,

validated by rigorous sampling, testing and quality protocols.

Its concrete must reliably achieve specified cube strengths at both seven and 28-day inter vals, consistent with the company’s detailed structural concrete specifications.

Furthermore, it must ensure long-term durability under environmental and operational stresses, aligning with projected structural design lives.

Concrete production at this construction site adheres strictly to the client’s specification for structural concrete, which is aligned with the standards outlined in the South African

National Standards (SANS) 1200 series and SANS 10400 structural codes. Quality control measures are meticulously implemented to ensure structural safety and durability.

“Durable concrete has become increasingly important due to the widespread deterioration of reinforced concrete structures very early on in their lifecycles. Extensive maintenance and repairs increase the operating costs of infrastructure over their lifecycle, placing an enormous strain on already-stretched public sector budgets,” explains Carl White, Managing Director of Spraylock Africa.

He adds that concrete corrosion is a serious problem in South Africa, especially in coastal and industrial areas where chlorides and sulphate attacks are common. “For example, studies of structures in the Western Cape have revealed severe concrete structure corrosion damage, requiring major repairs to enable them to meet their design lives. In inland areas, such as Johannesburg, carbonation is

For the power station study, concrete panels were cast on site and then treated with SCP P3 Industrial. The tests confirmed that it offers a reliable and quantifiable improvement in service life and structural integrity

CEMENT & CONCRETE

a significant issue, compounded by the region’s drier climate,” he says.

Testing colloidal silica-treated concrete Two 600 × 400 × 150 mm concrete panels that were cast on a power station site and then treated with SCP P3 Industrial were tested for durability. They were cast using a W40 concrete mix. This durable concrete with a 40 MPa compressive strength was designed by a prominent civil engineering consultancy and cured using conventional, tried-and-tested methods.

The tests were under taken by Roadlab Laboratories and Specialised Concrete Consulting Services (SCCS). “Our tests confirm that SCP offers a reliable and quantifiable improvement in the service life and structural integrity of concrete infrastructure,” says SCCS Concrete Technologist, Jacques Steyn.

He explains that the tests were undertaken strictly according to the South African National Standards’ concrete durability testing standard, with the exception of certain modifications to facilitate the collection of specific data required for the assessment. “As opposed to trimming the first 5 mm of the core samples, they were cut into four sections, each 30 mm in length and about 2 mm in thickness. These sections were tested sequentially to determine SCP’s penetration effectiveness,” he expounds.

The samples underwent Oxygen-Permeability Index (OPI) testing to determine carbonation resistance and Chloride Conductivity Index (CCI) testing, a proxy for chloride diffusion.

Chloride-ion resistance is one of the most important measures for concrete durability, considering that this type of attack is one of the leading causes of concrete deterioration. Up to 40% of concrete deterioration worldwide can be attributed to chloride attack.

Chloride-ions enter concrete via its many interconnected capillary structures causing corrosion of reinforcing steel, which provides concrete structures with their strength.

Due to their electro-chemical nature, chlorideions break down the passive layer around reinforcing steel even without a decline in pH levels. Once the passive layer has been compromised and chloride-ions contact steel, they initiate corrosion. The oxide resulting from corrosion is ver y porous and takes up to 10 times the volume of steel, causing cracking, spalling and eventually failure – if left unattended.

There are two main sources of chlorideions: the concrete mix components and the surrounding environment. The first could derive from unwashed aggregates and sand, as well

as admixtures, and the second from sea-salt spray, direct seawater wetting, chloride-rich soil deposits and chemicals.

The South African chloride test entails the measurement of a sample’s electric conductivity.

The specimen is dried in an oven and vacuum presaturated with a 5 M NACI solution (five moles of sodium chloride for every litre of solution). It is placed between two cells containing 5 M NACI solution. A potential difference is applied across the sample, causing a movement of chlorideions, and the corresponding current used to calculate the concrete’s conductivity. In turn, this is related to the concrete’s resistance to chlorideion ingress.

Carbonation is an electrochemical reaction when carbon dioxide reacts with cement hydration products, such as calcium hydroxide, forming carbonic acid and subsequently calcium carbonate or calcite. This reaction reduces concrete’s pH, resulting in the de-passivation of the steel reinforcement, which initiates corrosion.

While in the beginning carbonation fills concrete pores and therefore reduces it permeability, micro cracks and shrinkage will occur over time, exposing the concrete to deleterious agents, such as sulphates, contributing to cracking and spalling.

The South African OPI test entails measuring the pressure decay of oxygen passed through a concrete disc placed in a falling head permeameter. A pressure gradient is applied across the test specimen and the pressure decay in the pressure cell monitored over time.

Colloidal silica’s efficacy validated All SCP-treated concrete samples achieved > 10 OPI, denoting a very low gas permeability, and the 0.70–0.89 mS cm⁻¹ CCI values achieved fall in the “Excellent” range and well below the 2.0 mS cm⁻¹ site-acceptance threshold.

“The combined results confirm that the SCP P3 Industrial-treated panels feature a dense and effectively sealed microstructure that can easily withstand aggressive environmental conditions that contribute to corrosion,” Steyn says.

“Impressively, these durability gains were achieved at a depth of at least 94 mm, confirming SCP’s deep and thorough penetration capacity. The average OPI results for SCP treated samples were 10,96 and the durable control samples average was 10,33. The CCI for the SCP treated samples were 0,51 and the durable concrete samples average was 0,62,” White elaborates.

Sheldon White, Spraylock Africa’s National Sales Manager, explains that SCP P3 Industrial penetrates concrete via its accessible capillary

Durable concrete has become increasingly important due to the widespread deterioration of reinforced concrete structures very early on in their lifecycles

system, reacting with available free alkali to form calcium silicate hydrate (C-S-H), which is essentially more concrete.

“This action permanently protects the matrix of new or existing concrete after a single spray application by one of our many approved SCP applicators throughout Africa,” he says.

White expounds that the amorphous silicon dioxide particles contained in SCP P3 Industrial are less than 100 nanometres in size and suspended in water. Their extremely small size provides a tremendous amount of reactivity and pozzolanic potential – even greater than condensed silica fume. This reaction takes place in the capillary voids, filling them with more calcium-silicate hydrate (C-S-H), the same product that provides concrete with its strength and durability traits. Even under hydrostatic pressure, the movement of water through concrete is restricted.

“This conclusion is supported by the observed correlation between the low CCI and high OPI values recorded in the first and third SprayLocktreated specimens. These values confirm the effectiveness of the treatment in blocking pore connectivity, which is critical in limiting ingress of deleterious agents. For comparative purposes, the untreated control concrete exhibited a relatively high OPI value of 10.33 × 10⁻¹⁰ m²/s, indicating a more permeable microstructure.

In contrast, the SprayLock-treated panels demonstrated a significant improvement in durability performance,” White concludes.

IMIESA September 2025

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CEMENT & CONCRETE

WHY CUTTING QUALITY IS CUTTING CORNERS ON SA’S FUTURE In a construction landscape where cost pressures are rising, AfriSam’s Amit Dawneerangen is raising a red flag, cautioning contractors that cutting corners on material quality may appear cost effective in the shor t term, but it compromises the long term per formance and value of infrastructure.

A

s Executive: Sales & Product Technical at AfriSam, Dawneerangen sees worrying signs of a growing trend – across both public and private sector projects – where the drive to reduce costs is resulting in widespread “buying down” on material quality.

Dawneerangen argues that the foundation of any durable and cost effective infrastructure project lies in the quality of materials used.

Cement, aggregates and readymix concrete must meet rigorous standards if structures are to withstand time and usage.

“Quality is the basis for longevity in construction projects,” he says. “And yet, there is an increasing appetite for lower quality alternatives that may meet the immediate budget but not the design intent or long term performance requirements.”

Infrastructure investment remains one of the most powerful tools for economic growth, with a proven multiplier effect. But the benefits only materialise if the projects built are sustainable – both structurally and financially.

Dawneerangen points to AfriSam’s own commitment to quality assurance, noting that all its cement products are produced in ISO 9001-certified facilities and conform to SANS 50197 requirements.

On road projects especially, material testing is critical. AfriSam applies globally recognised methodologies such as Los Angeles Abrasion, Polished Stone Value and California Bearing Ratio tests. Its quarries produce a range of products from G1 to G7 for layerworks in line

44 IMIESA September 2025

AfriSam continues to prioritise quality across its cement, aggregate and readymix concrete operations

with COTO and other relevant specifications and most also supply stone and crushed sand for asphalt production.

Yet despite the availability of tested compliant materials, Dawneerangen is seeing a shift in specifications that opens the door to lesser products. From an aggregate perspective, the traditional “blue” rock – competent material mined from deeper layers – has always been preferred for its high compressive strength.

Increasingly, however, this is being blended with overburden or “brown” material, resulting in downgraded specifications. These blends are being embraced as a cheaper alternative even though they may compromise structural integrity.

The practice has also led to a rise in illegal mining operations where unregulated borrow pits offer free-dig material with minimal processing costs. “There is no drilling or blasting required. It is a quick fix for contractors chasing margins,” says Dawneerangen. “But it undermines legal operators who invest in compliance and quality.”

The same trend is evident in the readymix sector. AfriSam, traditionally known for supplying premium strength concrete upwards of 35 MPa, has seen demand shift below the 30 MPa mark. “The drop in average strength tells its own stor y. Affordability is driving decisions but at what long term cost?”

Dawneerangen emphasises that using subpar materials often results in hidden costs. Inconsistent properties can lead to rework, premature failure and costly delays.

“The right material used in accordance with design specifications eliminates the need for

unscheduled corrective work,” he says. “Socalled cheap materials can end up being very expensive.”

Working with a reputable supplier, he believes, is non-negotiable. AfriSam’s vertically integrated offering – from quarry to cement plant to readymix site – ensures that quality is consistently monitored throughout the value chain. The company’s SANAS 17025-accredited Centre of Product Excellence collaborates closely with customers to tailor solutions to specific applications, backed by in-house labs and quarterly testing.

Dawneerangen also notes the importance of sourcing aggregate from legally registered quarries recognised by industry bodies like ASPASA, which helps regulate surface mining practices. ASPASA conducts audits and drives continuous improvement through its technical committees, providing vital industry oversight.

Unfortunately, no such structure exists in the readymix industry which, he says, has become highly deregulated. This has created space for opportunistic suppliers who under-yield or engage in questionable practices, often undercutting responsible operators on price while delivering poor product quality.

Ultimately, Dawneerangen’s message is clear. South Africa cannot afford to sacrifice infrastructure integrity for short term savings.

“Adherence to quality control guarantees successful execution of projects on time and within budget. With the role that infrastructure plays in our country’s future, we must stop seeing quality as optional. It is the smartest investment we can make.”

CEMENT UNDER THE MICROSCOPE REDEFINING BUILDING ANALYSIS

C

ement is the backbone of modern infrastructure – shaping everything from towering skyscrapers to resilient bridges and everyday housing. But ensuring that cement delivers on strength, durability, and sustainability requires more than just production.

It demands precise analysis.

In the age of smarter construction, cement analysis has evolved into a multidimensional process that goes beyond simple quality checks. By unlocking the microscopic secrets of cement, researchers, engineers, and manufacturers can push the boundaries of what building materials can achieve.

Meet us at 2025 IMESA Conference Stand 41 29–31 October

Why cement analysis matters The performance of cement influences not only the longevity of structures but also their environmental footprint. From reducing emissions during production to optimising durability in end-use applications, accurate analysis ensures that cement consistently meets global quality standards.

With construction projects under increasing scrutiny for safety, costefficiency, and sustainability, mastering cement analysis isn’t just an advantage – it’s essential.

From powder to performance: Techniques that transform Comprehensive cement characterisation requires a suite of advanced techniques that uncover insights at every stage of the material’s lifecycle: • Particle size and shape analysis: Understanding the distribution and morphology of cement particles helps optimise strength and reactivity, directly impacting setting time and durability.

• X-ray diffraction (XRD) for phase composition: Identifying crystalline phases ensures consistency and reveals how different formulations perform under diverse conditions.

• Rheological analysis: Studying flow behaviour of fillers and additives, along with stirring methods, helps design cement mixes that are workable yet strong.

• Hardness testing: Mechanical strength underpins structural integrity, making hardness evaluation indispensable for predicting performance.

• Moisture analysis: Accurate water content measurement is critical, as excess moisture can compromise storage stability and final strength.

Together, these methods provide a holistic view of cement quality and unlock opportunities for innovation in mix design, efficiency, and application.

Beyond cement: Expanding the horizon While cement remains the focal point, modern analysis techniques extend to other essential building materials such as concrete composites, fillers, and additives. This cross-material perspective enables engineers and manufacturers to refine the entire ecosystem of construction materials, creating more sustainable and higher-performing structures.

Transform Your Cement Analysis Anton Paar Instruments

Building the future with smarter analysis As the construction industry navigates challenges of resource efficiency and sustainability, cement analysis stands at the forefront of innovation. Those who embrace advanced characterisation methods won’t just keep up with evolving standards – they will lead the way towards safer, stronger, and greener buildings.

Don’t just follow the trend – shape it. Transform your approach to cement analysis today.

Download the free e-book Transform your Approach to Cement Analysis and gain deeper insights into cement characterisation techniques, practical applications, and how to elevate your building material expertise.

Link: http://bit.ly/4p8BhcD. Or contact Lorin Hosken for more information: Lorin.hosken@anton-paar.com.

Particle size and shape analysis of cement powder Phase composition identification using X-ray diffraction Rheological analysis to determine flow properties of cement For anyone in R&D, quality control, or engineering

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IMESA AFFILIATE MEMBERS

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PROFESSIONAL AFFILIATES

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T O T A L

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IMILE ZIMILE

Consulting En ineers

AECOM siphokuhle.dlamini@aecom.com AFI Consult banie@afri-infra.com ARRB Systems info@arrbsystemssa.com Asla Construction (Pty) Ltd johanv@asla.co.za BMK Group brian@bmkgroup.co.za Bosch Projects (Pty) Ltd mail@boschprojects.co.za BVI Consulting Engineers marketing@bviho.co.za Camjet info.jhb@camjet.co.za CCG puhumudzo@ccgsytems.co.za / info@ccgsystems.co.za Civtech Engineers (Pty) Ltd admin@civtech.biz Corrosion Institute of Southern Africa secretary@corrosioninstitute.org.za Dlamindlovu Consulting Engineers & Project Managers info@dlami-ndlovu.co.za EFG Engineers info@efgeng.co.za Elster Kent Metering Mark.Shamley@Honeywell.com EMS Solutions paul@emssolutions.co.za ENsync Engineers info@ensync.africa ERWAT mail@erwat.co.za Gabion Baskets mail@gabionbaskets.co.za GIBB marketing@gibb.co.za GIGSA secretary@gigsa.org GLS Consulting info@gls.co.za Gorman Rupp Cordeiro@gormanrupp.co.za Gudunkomo Investments & Consulting info@gudunkomo.co.za Hatch Africa (Pty) Ltd info@hatch.co.za HB Glass Filter Media info@hardybulkinglass.com Herrenknecht schiewe.helene@herrenknecht.de HSA Technology (Pty) Ltd cs@hubersa.com Hydro-comp Enterprises info@edams.co.za IMQS Software (Pty) Ltd shemine.adams@imqs.co.za Infrachamps Consulting info@infrachamps.co.za INFRATEC info@infratec.co.za Institute of Waste Management of Southern Africa iwmsa@iwmsa.co.za IQHINA Consulting Engineers & Project Managers info@iqhina.co.za iX engineers (Pty) Ltd hans.k@ixengineers.co.za Izinga Holdings info@izingalabezi.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@ct.kanteys.co.za Kitso Botlhale Consulting Engineers info@kitsobce.co.za KSB Pumps and Valves (Pty) Ltd salesza@ksb.com KUREMA Engineering (Pty) Ltd info@kurema.co.za Lektratek Water general@lwt.co.za Loshini Projects muzi@loshini.co.za m4a fagan@m4a.co.za Makhaotse Narasimulu & Associates mmakhaotse@mna-sa.co.za Mariswe (Pty) Ltd neshniec@mariswe.com Martin & East gbyron@martin-east.co.za M & C Consulting Engineers (Pty) Ltd info@mcconsulting.co.za Mhiduve adminpotch@mhiduve.co.za MPAMOT (Pty) Ltd mpumem@mpamot.com Mvubu Consulting & Project Managers miranda@mvubu.net NOTHI Group info@nothigroup.co.za NTGR Engineering info@ntgr.co.za Nyeleti Consulting naidoot@nyeleti.co.za Prociv Consulting & Projects Management amarunga@prociv.co.za Rainbow Reservoirs quin@rainbowres.com Re-Solve Consulting (Pty) Ltd maura@re-solve.co.za Ribicon Consulting Group (Pty) Ltd info@ribicon.co.za Royal HaskoningDHV francisg@rhdv.com SABITA info@sabita.co.za SAFRIPOL mberry@safripol.com SAGI annette@sagi.co.za SALGA info@salga.org.za SAPPMA admin@sappma.co.za / willem@sappma.co.za SARF administrator@sarf.org.za.co.za SBS Water Systems marketing@sbstanks.co.za Silulumanzi Antoinette.Diphoko@silulumanzi.com Siroccon International (Pty) Ltd admin@siroccon.co.za SiVEST SA info@sivest.co.za Sizabantu Piping Systems (Pty) Ltd proudly@sizabantu.com Siza Water (RF) Pty Ltd PA@sizawater.com Sky High Consulting Engineers (Pty) Ltd info@shconsultong.co.za SKYV Consulting Engineers (Pty) Ltd kamesh@skyv.co.za Smartlock jp.alkema@smartlock.net SMEC capetown@smec.com SOUTH AFRICAN VALUE EDUCATION Sabiha@savegroup.co.za Southern African Society for Trenchless Technology director@sasst.org.za SRK Consulting jomar@srk.co.za Structa Group info@structatech.co.za Superior Filtration (Pty) Ltd info@superior-filtration.com TPA Consulting roger@tpa.co.za Ultra Control Valves peter@ultravalves.co.za V3 Consulting Engineers (Pty) Ltd info@v3consulting.co.za Videx Storage Tanks sales@vidextanks.co.za VIP Consulting Engineers esme@vipconsulting.co.za VNA info@vnac.co.za Water Institute of Southern Africa wisa@wisa.org.za Wam Technology CC support@wamsys.co.za Wilo South Africa marketingsa@wilo.co.za WRCON ben@wrcon.co.za Zimile Consulting Engineers info@zimile.co.za Zutari charmaine.achour@zutari.com

IN MEMORIAM

A FINAL

SALUTE

TO DAWIE BOTHA

I

ndustry stalwart David Botha (born 1947) passed away on 1st September 2025 after bravely fighting recurring cancer, while voluntarily continuing to serve the science, engineering, technology (SET) and innovation community in South Africa, as he had done for decades, up to the very end.

Dawie, as he was popularly known, was the first and immediate past chairperson of the NSTF-proSET Sector (Professionals in Science, Engineering and Technology), serving for two decades since his appointment in 2005.

It was under his leadership of the proSET Committee that the largest membership sector of the National Science and Technology Forum (NSTF), currently representing over 50 professional and learned societies in South Africa, was established.

On the occasion of the 30th anniversary of NSTF’s establishment in 1995, Dawie was honoured for his volunteership, selfless service and outstanding contributions within the community, to both the NSTF and the country, as only the third recipient of the NSTF Ukhozi Award.

The ceremony took place at the NSTF-South32 Awards held in Cape Town during July 2025.

Professional career highlights A professional civil engineer, Dawie began his career with the South African Railways and Harbours Administration, and thereafter worked for the Potchefstroom and Richards Bay municipalities, and the South African Housing Trust. In 1990 he took up the role of Executive Director at the South African Institution of Civil Engineering (SAICE) – a position he held for 20 years, alongside his voluntary participation and leadership within the NSTF community.

He was an Honorary Fellow of SAICE, as well as a Fellow of the South African Academy of Engineering (SAAE) and the Institute of Municipal Engineering of Southern Africa (IMESA). Dawie joined IMESA in July 1976, was awarded Fellow status in 1986, and took up Retired Fellow status from 2013. During his active membership role within IMESA he supported several IMESA projects via his engagement with the Development Bank of Southern Africa.

He was also the recipient of the SAICE Presidential Award in 1995, and recipient of an NSTF Award in the management category in 2011.

Among his many achievements, he authored the book Travels with Civils, published in 2014, which recounts an in-depth history of civil engineering in South Africa. Dawie was also a retired Councillor of the Democratic Alliance, serving the Overstand Municipality in Hermanus, Western Cape.

IMESA extends its deepest condolences to his beloved wife, Ria and children, Jac, Johnet and Maartje, friends and family, his business associates and colleagues. He will be sorely missed.

IMIESA September 2025

47

WASTE MANAGEMENT

Municipal and industrial recycling ventures strengthen communities Forming par t of a series of municipal par tnerships being rolled out countr ywide, Polyco and Swellendam Local Municipality have officially joined forces through an agreement to drive systemic change in waste management in the town.

T

his vision focuses on a shared commitment between Polyco and Swellendam Municipality to tackle illegal dumping, expand access to recycling infrastructure and generate economic opportunities, particularly through the development of a Packa-Ching buy-back centre, which will pay community members for the waste they collect.

Under Polyco’s national Packa-Ching programme, to date over R27 million has been paid out to communities for their recyclables, and some 27 million kilogrammes of waste have been diverted from landfills. This collaboration also includes the joint rollout of education and awareness programmes in schools and communities, and additional suppor t for informal waste reclaimers.

In terms of its agreement with Swellendam Municipality, Polyco will provide funding, training, and technical assistance to support implementation of their various waste management programmes over the next two years. In turn, the municipality will facilitate land access, coordinate community involvement, and enable the implementation of priority infrastructure as per their approved budget.

“Our latest partnership with Swellendam is part of a broader strategy to empower local communities and drive environmental change from the ground up,” says Patricia Pillay, CEO of Polyco – one of South Africa’s leading Producer Responsibility Organisations (PROs) under the countr y’s Extended Producer Responsibility (EPR) regulations.

Echoing this vision, Swellendam Municipality has positioned circular economy principles at the core of its waste strategy. “Polyco’s Packa-Ching programme is instrumental in unlocking this value,” says Johan van Niekerk, Manager: Waste and Environmental at Swellendam Municipality.

“Through it, residents earn credits for recycling that can be spent at local businesses. Our shared goal is that ever yone recognises the worth of waste, chooses to recycle, and keeps both money and materials circulating in Swellendam and litter off the ground.”

Cape Town pilot In an allied initiative, Polyco, in partnership with City of Cape Town Mayoral Committee Member for Urban Waste Management, Alderman Grant Twigg, has launched a pilot community recycling hub in Scottsdene, Northpine and surrounding areas. Located at a local Early Childhood Development centre, the hub will provide a safe, organised collection point for recyclables.

Polyco has provided a fully equipped container to serve as the hub, together with protective clothing, recycling trolleys, household separation bags, and branded materials to build awareness.

Training has also been delivered to participants, covering practical recycling skills, safe collection practices, and small business development.

Gauteng The key to these recycling initiatives is downstream processing capacity. A case in point is the commissioning in late May 2025 of Enviro Plastic Africa’s (EPA’s) new plastic

wash plant in Vereeniging, suppor ted by a R2.2 million investment from Polyco. The new plant has enabled EPA to push its throughput from +/-20 tonnes to +/-100 tonnes per month.

Additionally, the plant’s advanced washing technology allows the facility to produce cleaner, higher-quality recycled plastics more efficiently.

Since its founding in 2023, EPA has worked closely with Polyco on local recycling initiatives.

Polyco’s support has not only enabled the rollout of the wash plant but also helped strengthen EPA’s broader asset base, including a 500 kg/hour wet extruder and pelletiser, and a 1 000 kg/hour dry and lump crusher line. These capital expenditure gains at EPA represent a major step in boosting Gauteng’s overall recycling capacity.

EPR objectives As demand for sustainable recycling solutions grows, Polyco remains committed to investing in the partners and infrastructure that deliver measurable impact and systemic change.

The EPR regulations require producers to take responsibility for the full lifecycle of their packaging by funding its recovery, recycling, and responsible disposal. Polyco manages these obligations on behalf of its 700-plus members, investing EPR fees into infrastructure, enterprise development, and partnerships.

In terms of positive impact, since the inception of the EPR in 2022, Polyco has diverted over 458 000 tonnes of plastic from landfill, invested more than R300 million into the plastics recycling and collection sector, and supported 216 projects nationwide.

INDEX TO ADVERTISERS Anton Paar APE Pumps & Mather+Platt BLOC Contractors Gabion Baskets IMESA

48 IMIESA September 2025

45 23 12 6, OFC 2, 39, 41

KSB Pumps and Valves

27

SAPPMA

21

Liebherr

5

Sizabantu Piping Systems

IFC

Rainbow Reservoirs

31

Solfab

OBC

17, 36

Xylem

35

Rand Water

IMESA The official magazine of the Institute of Municipal Engineering of Southern Africa www.imesa.org.za

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