IMIESA March 2023

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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

INDUSTRY INSIGHT

Steel pipes: the backbone of any water network Kenny van Rooyen, Managing Director, and Callum Storar,

Water Demand Management & Water Security The two recurring extremes – droughts and floods

Contract Sales Manager, Hall Longmore

The future of smart water and energy

Roads & Bridges Upgrading low-volume routes

Waste & Recycling Delving into landfill design and development

IN THE HOT SEAT Our longstanding reputation as pump innovation leaders is built on a solid foundation of experience, technology and a passion for developing fit-for-purpose solutions.” John Montgomery GM for APE Pumps and Mather+Platt I S S N 0 2 5 7 1 9 7 8 Vo l u m e 4 7 N o . 0 1 • J a n u a r y 2 0 2 2 • R 5 5 . 0 0 ( i n c l . VAT ) I S S N 0 2 5 7 1 9 7 8 Vo l u m e 4 8 N o . 0 2 • M a r c h 2 0 2 3 • R 5 5 . 0 0 ( i n c l . VAT )

INSIDE

VOLUME 48 NO. 02 MARCH 2023

32 Regulars www.infrastructurenews.co.za www.infrastructurenews.co.za

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

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

INDUSTRY INSIGHT

Steel pipes: the backbone of any water network

Water Demand Management & Water Security

Waste & Recycling

Editor’s comment President’s comment Index to advertisers

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Cover Story The future of smart water and energy

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The two recurring extremes – droughts and floods

Kenny van Rooyen, Managing Director, and Callum Storar, Contract Sales Manager, Hall Longmore

Africa Round-up

Kendal’s new ADF design promotes water reuse Growing market for waste challenges So, your municipality needs a new landfill?

Delving into development and design Aloes Cell 3B extension incorporates piggyback lining

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Infrastructure news from around the continent 10

Renewable Energy & Electrification

Hot Seat A pump leader for 71 years and counting The future of smart water and energy

Roads & Bridges Upgrading low-volume routes

Waste & Recycling Delving into landfill design and development

IN THE HOT SEAT Our longstanding reputation as pump innovation leaders is built on a solid foundation of experience, technology and a passion for developing fit-for-purpose solutions.” John Montgomery GM for APE Pumps and Mather+Platt

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Industry Insight Steel pipes: the backbone of any water network

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For any industrial or municipal entity considering a renewable power-driven water or wastewater treatment approach, the cost of implementation is relative. The primary concern is uninterrupted production, coupled with mediumto longer-term energy savings, says NJ Bouwer, executive at NuWater, which is pioneering the integration of solar as well as hybrid systems to run its customdesigned systems. P6

IN THE HOT SEAT Optimal fluid transfer is central to all process industries – from water and wastewater to the petrochemical and energy sectors – and pumps are the driving force that makes this possible. IMIESA speaks to John Montgomery, GM for APE Pumps and sister company Mather+Platt, about the group’s innovative approach to ensuring sustained delivery. P12

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WASTE & RECYCLING

Economics Infrastructure targets and engagement

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Staying relevant in a changing sector

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Groundwater Making rural water supply more sustainable

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Perfecting South Africa’s Water Networks Scientific ways to carry out water master planning and execution

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Instrumentation All in one, adaptable flow meter

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World Water Day If the world were 100 people

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Water Demand Management & Water Security Magnetic water meters save utilities millions 28 How do we fix SA’s critical water challenges? 31 The two recurring extremes – droughts and floods 32

Leading Water Projects Making an impact through water treatment infrastructure VEHICLES & EQUIPMENT

The Terraforce Book of Ideas

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Roads & Bridges

Water & Wastewater

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Concrete Retaining Block Systems

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ON THE COVER

Solar tax rebates a step in the right direction Cape Town’s cash-for-power programme The grid and its digital twin Software designed to facilitate wheeling

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Research team develops practice manual for paved low volume roads projects

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Health & Safety Revised OHS Act requires far stricter compliance

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Vehicles & Equipment Meeting readymix demand in Bamako A decade of class leadership in trucking

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Cement & Concrete Concrete technologists vital for preserving SA’s infrastructure Surge in African construction creates niche opportunities The downside to quality shortcuts

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Waterproofing Sika SA adds Index range to local line-up

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INDUSTRY INSIGHT An industry pioneer since 1924, Hall Longmore’s commitment to research and development continues to refine its class leadership in the steel pipe sector.

IMIESA speaks to Kenny van Rooyen, managing director, and Callum Storar, contract sales manager, about the key role of steel in service delivery. P14

The prosperity of every community depends on high quality water, managed as efficiently as possible. It’s a big responsibility, with some tough challenges. We’ve made it our business to understand the demands.

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EDITOR’S COMMENT MANAGING EDITOR Alastair Currie SENIOR JOURNALIST Kirsten Kelly JOURNALIST Nombulelo Manyana EDITORIAL COORDINATOR Ziyanda Majodina HEAD OF DESIGN Beren Bauermeister CHIEF SUB-EDITOR Tristan Snijders CONTRIBUTORS Chetan Mistry, Sibusiso Mjwara, Dwibin Thomas PRODUCTION & CLIENT LIAISON MANAGER Antois-Leigh Nepgen GROUP SALES MANAGER Chilomia Van Wijk BOOKKEEPER Tonya Hebenton DISTRIBUTION MANAGER Nomsa Masina DISTRIBUTION COORDINATOR Asha Pursotham SUBSCRIPTIONS subs@3smedia.co.za ___________________________________________________ ADVERTISING SALES KEY ACCOUNT MANAGER Joanne Lawrie Tel: +27 (0)11 233 2600 / +27 (0)82 346 5338 Email: joanne.lawrie@3smedia.co.za ___________________________________________________

PUBLISHER Jacques Breytenbach 3S Media Production Park, 83 Heidelberg Road, City Deep Johannesburg South, 2136 PO Box 92026, Norwood 2117 Tel: +27 (0)11 233 2600 www.3smedia.co.za ANNUAL SUBSCRIPTION: R600.00 (INCL VAT) ISSN 0257 1978 IMIESA, Inst.MUNIC. ENG. S. AFR. © Copyright 2023. 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: Ollah Mthembu Tel: +27 (0)82 823 7104 Email: np@imesa.org.za SOUTHERN CAPE KAROO Secretary: Henrietta Olivier Tel: +27 (0)79 390 7536 Email: imesasck@imesa.org.za WESTERN CAPE Secretary: Michelle Ackerman Tel: +27 (0)21 444 7114 Email: imesawc@imesa.org.za

Finding the optimum balance to energy and water demand

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ater scarcity and adequate supply remain serious concerns, with somewhere between two and three billion citizens globally currently experiencing water shortages, according to the UN World Water Development Report 2023. Unless addressed, the situation will continue to deteriorate, with rising population numbers exacerbating the problem.

Within the South African context, the opportunities to address local challenges are reflected in the SAICE 2022 Infrastructure Report Card. Overall, South Africa scored a C+ (‘Satisfactory for Now’) for the supply of potable water to major urban areas, and a C- for sanitation (including wastewater). More concerning is the D- (‘At Risk of Failure’) for bulk water resources.

Going forward, it’s clear that the impacts of climate change will require a major mindset shift away from a conventional reliance on surface water to areas like wastewater reuse and desalination. We also need to urgently stem non-revenue water losses that cost utilities millions in lost revenue and further threaten the country’s water security.

From an infrastructure perspective, South Africa’s Minister of Finance, Enoch Godongwana, stated during his Budget Speech in February 2023 that some R132.5 billion has been allocated for water and sanitation in the 2023/24 and 2025/26 financial years. If well invested in futureproof systems, this will certainly help to alleviate maintenance backlogs, as well as fund5 new developments that support residential and commercial expansion.

Combatting water shedding Another equally important allocation for 2023/24 to 2025/26 is the approximately R157.8 billion for energy, which is vital for sustaining our power and water security.

Current grid outages disrupt every element of our lives when pump stations, water and wastewater treatment plants experience extended stoppages, and reservoir storage levels drop to critical levels. As South Africa enters the winter period – where demand

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. _____________________________________________

Solar incentives While renewable energy is vital to combat climate change, it’s now rapidly becoming the ‘go-to’ option for South Africa as an immediate solution to our energy crisis, and the implementation of key national development goals.

Historically, there’s been a steady upward trend for wind, solar PV and CSP generation, collectively, as reflected in the CSIR Energy Centre’s recent statistics. This group’s contribution has risen from some 3 134 MW in 2016 to 6 230 MW in 2022.

Last year, that equated to some 16 TWh of energy produced compared to 176.6 TWh for coal.

While the gains have been moderate in the past, it’s certain that the pace of renewable implementation is going to accelerate exponentially. This will be spurred on by a surge in rooftop solar following the announcement of tax incentives for households and businesses.

In parallel, progressive metros are providing their own enabling frameworks. A prime example is the City of Cape Town, where – from June 2023 – businesses, and subsequently residents, with approved generation capacity will be paid NERSA-agreed-on tariffs to feed excess energy back into the municipal grid.

Many innovations are born out of necessity, and renewable energy is one of them. It’s also a trend that will shape the future of infrastructure designs in terms of process optimisation. In this respect, water demand management and energy are joined at the hip.

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.

www.infrastructurenews.co.za

IMESA

@infrastructure4

Infrastructure News

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

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

INDUSTRY INSIGHT

Steel pipes: the backbone of any water network

Kenny van Rooyen, Managing Director, and Callum Storar, Contract Sales Manager, Hall Longmore

Water Demand Management & Water Security The two recurring extremes – droughts and floods

Novus Holdings is a Level 2 BBBEE Contributor: novus.holdings/sustainability/transformation

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

can peak at around 33 000 MW (when available) – the challenges for municipalities and water utilities will intensify.

The future of smart water and energy

Roads & Bridges

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.

Upgrading low-volume routes

Waste & Recycling Delving into landfill design and development

IN THE HOT SEAT Our longstanding reputation as pump innovation leaders is built on a solid foundation of experience, technology and a passion for developing fit-for-purpose solutions.” John Montgomery GM for APE Pumps and Mather+Platt I S S N 0 2 5 7 1 9 7 8 Vo l u m e 4 7 N o . 0 1 • J a n u a r y 2 0 2 2 • R 5 5 . 0 0 ( i n c l . VAT ) I S S N 0 2 5 7 1 9 7 8 Vo l u m e 4 8 N o . 0 2 • M a r c h 2 0 2 3 • R 5 5 . 0 0 ( i n c l . VAT )

IMIESA March 2023

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PRESIDENT’S COMMENT

IMESA

ACCESS TO WATER AND SANITATION IS A HUMAN RIGHT Municipalities worldwide are essential enablers of infrastructure that suppor ts socioeconomic development. They implement national policies in sync with their own specific programmes to ensure all stakeholders receive equitable ser vices. Foremost among these is the provision of water and sanitation, which is a priority for national government and falls under the UN’s Sustainable Development Goal 6.

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great deal has been achieved in this respect since our democratic transition in 1994, but more needs to be done to bridge the gaps, alongside the need to keep pace with population and urbanisation trends. However, it’s equally important to ensure that rural communities are also serviced to the same standard, particularly those currently residing on land outside the municipal distribution network.

By definition, privately owned land is not controlled, leased or owned by the state.

Examples are wide-ranging and include church properties, commercial farms, game parks, mine-owned land, tribal land, trust properties and sectional title developments. Consultations within the provinces began in December 2022 and were completed in Februar y this year. Now it’s the public’s turn to provide their input and to understand the crucial importance of this endeavour.

Services on privately owned land A key development in this respect is the Department of Water and Sanitation’s (DWS’s) initiation of the Draft Water and Sanitation Services Policy on Privately Owned Land. As IMESA’s president, I attended the DWS’s launch of the national public consultation process, held at the Birchwood Hotel in Gauteng on 16 March 2023.

Water services authorities (WSAs) As IMESA, we view the draft policy as a highly encouraging development and, as municipal engineers, we will play a key role in its implementation going forward – from both a new build, as well as operations and maintenance perspective. More specifically, though, the responsibility for managing the process rests on the shoulders of the WSAs, which are legally responsible for executing water and sanitation services within their municipal jurisdiction. However, there are various routes to implementation.

As stated by the DWS, “The provision of water services to people living on privately owned land can be done by the municipality directly, or through a water services intermediary as captured and introduced within the Water Services Act (No. 108 of 1997).” A water services intermediary could be the landowner.

Sibusiso Mjwara, PrTechEng, MIMESA, MSAICE, MWISA, MIPET

An enabling regulatory environment The primar y objective of the draft policy is to establish an enabling regulator y environment, supported by suitable funding and grant mechanisms, in addition to municipal infrastructure development budget provision. That will include provision for indigent communities.

Collaboration between the public and private sector is fundamental to the success of the programme, including the willingness of private landowners to allow municipalities access to evaluate existing on-site water and sanitation facilities.

Where groundwater is being abstracted, for example, this would include ad hoc water quality testing. In terms of site access authorisation, this may require the amendment of municipal by-laws.

Either way, it’s a two-way partnership.

During the public consultation process, for example, some stakeholders, which included farmers, raised the issue of being excluded from certain ser vices.

These include scenarios where a pipeline ser vitude passes through their land, but with no improved ser vice spin-off for the landowner, or where infrastructure development takes place outside the farm boundar y with no downstream benefit. The point raised is that ever yone must benefit.

At this stage, the DWS says that the full extent of the envisaged infrastructure provision still needs to be determined via a census study, but the extent is certain to be significant.

IMIESA March 2023

5

COVER STORY

THE FUTURE OF

smart water and energy For any industrial or municipal entity considering a renewable-power-driven water or wastewater treatment approach, the cost of implementation is relative. The primar y concern is uninterrupted production, coupled with medium- to longer-term energy savings, says NJ Bouwer, executive at NuWater, which is pioneering the integration of solar as well as hybrid systems to run its customdesigned systems.

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technology-driven engineering leader that prides itself on innovation, NuWater designs, builds, finances, operates and maintains water and wastewater treatment plants for the South African and international market, both for public and private clients.

“The emphasis is on achieving optimal efficiencies by selecting the best technology fit for our client’s process requirement, with examples including the treatment of contaminated groundwater, seawater desalination and complex industrial effluent utilising various filtration techniques,” explains Bouwer, adding that key technologies

NJ Bouwer, executive at NuWater

employed by NuWater include ultra-lowpressure reverse osmosis (RO), nanofiltration, ultraviolet water purification treatment and ultrafiltration.

The starting point, however, is the available power source, which is always top of mind, from both a cost and availability perspective.

This is especially the case in South Africa, where daily extended power outages – dubbed ‘load-shedding’ – continue to occur, setting off a chain of negative reactions. In the municipal potable water space, for example, load-shedding impacts the entire network from treatment, pumping, and conveyance to reduced reservoir capacities, often resulting in water shortages, or ‘water-shedding.’

A NuWater solar-powered water treatment package plant installed for a remote operation

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There are various contributing factors that have resulted in this power crisis – a key one being major maintenance backlogs on South Africa’s ageing coal-fired power stations. While these are scheduled to be decommissioned over time as part of South Africa’s Just Energy Transition away from fossil-fuel-derived energy to greener alternatives – like wind, solar and bioenergy – that doesn’t solve the immediate power gap.

Intelligent plants that are energy efficient “Clearly, renewable energy is an environmental imperative, plus it makes economic sense; however, in our case, it’s now an immediate

COVER STORY

socio-economic imperative as South Africa faces a potential collapse of its conventional coal-fired grid. This is having a catalytic effect, significantly accelerating the desire to adopt renewables as a power risk mitigation measure. This is spurring huge demand for NuWater’s high-efficiency, intelligent-energypowered plant solutions,” Bouwer continues.

Another driving factor is the historically high cost of energy in South Africa with Eskom, the country’s national power utility, recently announcing further major tariff hikes for 2023.

This is another pressing motivation to find offgrid alternatives.

Depending on the scale and feedwater qualities, water and wastewater treatment can be somewhat energy intensive if the correct pairing of technologies is not selected. For desalination, for example, the cost of running purely on grid power can be 60-70% of the plant’s overall operational expenditure. “That’s a big incentive for considering a switch to ‘free’ off-grid renewable energy or looking at a hybrid system. The latter might combine conventional power, renewables and backups like diesel or gas turbine gensets. It all depends on the baseload requirements,” says Bouwer.

A question of solar space If space limitations are not an issue, then huge solar arrays can be established. Classic examples can be found in the Middle East, where extensive solar fields power the world’s largest desalination plants, supporting the development of flourishing metropolises by harnessing two natural resources – sunlight and seawater. Other key ingredients are enabling government policies, and the right geographic location.

An internal view of the inverter and battery storage setup housed within a mobile container forming part of a NuWater treatment plant powered by renewable energy

To date, NuWater has installed and commissioned solar-powered package plants in South Africa and Africa. These have typically been in the range of 50 000-150 000 ℓ/day, operating at a power consumption of 0.2-1.2 KWh/m3. The amount of energy required depends on the degree of water or wastewater contamination.

Among the cases in point are four standalone solar-powered water purification plants that NuWater has designed, installed and commissioned in Pemba, Mozambique, to serve remote rural villages. The treatment

For communities in need, NuWater’s solar-powered modular plants are certainly a game changer and could help bridge the divide for a wide range of stakeholders…” strategy here is particularly intensive, entailing the removal of silica, organics and high levels of salinity from in-situ groundwater to produce clean, safe potable water.

Filling infrastructure gaps For communities in need, NuWater’s solarpowered modular plants are certainly a game changer and could help bridge the divide for a wide range of stakeholders affected by loadshedding, inadequate or no existing services.

“Let’s take the example of a rural school accommodating 1 000 learners, with each pupil requiring around 5 ℓ/day. By installing a solar-powered package plant, and dependent on the feedwater source, you’d only need around 0.5 kWh/m3 to treat some 5 000 ℓ/day of potable water. To achieve this, the plant would need up to eight 400 W solar panels,” Bouwer explains.

Industrial scalability Another parallel development is the growth

IMIESA March 2023

7

COVER STORY Port Alfred

Assembly in progress on an RO package plant at NuWater’s facility in Cape Town

in demand from industrial clients, some of whom are installing their own large-scale rooftop and allied solar power generation systems to run critical processes off the grid.

In a recent example, NuWater has secured a contract to treat some 500 000 ℓ/day of water, sourced from an on-site borehole, for an FMCG manufacturer. In this instance, NuWater also treats the downstream industrial effluent.

“Advancements in battery technology will continue to extend the boundaries of energy storage capabilities, which includes industry research and development on electrolyte batteries. The cost of solar panels, battery storage and inverters also keeps falling, making it more and more attractive to go the selfgeneration route. There are also opportunities to

dovetail systems with other options like wasteto-energy,” says Bouwer.

Tailored process solutions for municipalities Within its broad portfolio of solutions, NuWater is currently providing specialist services for municipalities across South Africa. Examples include eMalahleni Local Municipality (Witbank) in Mpumalanga, George Municipality in the Western Cape, and Ndlambe Municipality (Port Alfred) in the Eastern Cape.

In the case of eMalahleni, the municipality’s existing water treatment works was not set up to remove mining-related contaminants.

In response, NuWater has installed a modular plant on-site to meet this specific process requirement.

Meanwhile in George, the municipality has taken its main system offline in order to maintain and upgrade the existing treatment works. During this period, NuWater’s plants are responsible for augmenting the town’s potable water supply.

An aerial view of NuWater’s package plant solution for eMalahleni Local Municipality

An artist’s impression of a NuWater solar-powered treatment plant concept

8 IMIESA March 2023

NuWater’s scope of works in Port Alfred is complex and underscores its turnkey capabilities. This seaside tourism destination has been subjected to crippling droughts in recent years. The only viable option was desalination.

“We’ve installed what we believe are the highest efficiency RO systems that are commercially available and affordable to endusers,” says Bouwer.

NuWater’s solution incorporates specialised booster sets incorporating energy recovery systems. Low-energy membranes further reduce power demand. “The plant’s setup has also been purpose-designed so it is ultraefficient on the cleaning cycle, ensuring that energy consumption is as low as possible,” Bouwer continues.

For Port Alfred, solar power was ruled out as an option due to the location of NuWater’s plants in shady ravines where the available sunlight was considered insufficient for the plant’s baseload requirements.

Some renewable possibilities For mining, industrial and municipal clients, there are ‘out of the box’ water treatment options to consider if South Africa enters Stage 8 in the winter months. Stage 8 or removing 8 000 MW from the grid would result in some 12 hours of load-shedding in a 24-hour period, especially devastating for end-users.

One scenario would be to use solar power (at scale and space permitting) combined with battery storage to process the bulk of the daily potable water requirement within a 10- to 12-hour window and then store it for 24-hour use in reservoirs or tanks. The only power then needed during load-shedding, or at night, would be booster pumps for water distribution, which could be run via gensets or batteries.

“For municipalities, the massive volumes of water that would need to be stored and then pumped at a steady rate could prove to be challenging, but the concept is workable in theory,” adds Bouwer.

“One thing is certain. Climate change threats, spiralling conventional power costs, and loadshedding all make renewable energy very attractive. It’s a win-win for the environment, and vital for our future water security,” Bouwer concludes.

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INFRASTRUCTURE NEWS

FROM AROUND THE CONTINENT

SENEGAL Malicounda power project now fully operational Located in Mbour, 85 km south of Senegal’s capital Dakar, the plant is anticipated to deliver 956 GWh of power per year, which represents a 17% increase in the countr y’s power generation capacity.

Wär tsilä delivered the 130 MW Flexicycle power generation technology. The Malicounda power plant comprises seven 18V50 engines and a steam turbine, combining the advantages of a simple-cycle operation with the high efficiency of a combined cycle plant.

Its fast load-following power capability means that the plant is ideally suited to maintain system reliability, and able to offer the flexibility needed as intermittent renewable energy is progressively added to Senegal’s

power grid. The plant will initially operate on heavy fuel oil; however, there is an option to conver t the plant to run on locally supplied gas from the GTA field once it becomes available, fur ther lowering the cost of energy.

The Malicounda power plant is a central par t of the government’s Plan Sénégal Emergent to strengthen the countr y’s emerging economy and provide electricity access to ever yone by 2025. It was one of the first public-private par tnership (PPP) projects in West Africa, involving the African Development Bank, Africa50, the Infrastructure Development Fund for Africa and Senelec (Senegal’s state power utility), setting a model of cooperation to meet the continent’s growing energy needs.

Matelec (the plant EPC contractor) will operate the plant and Wär tsilä has a 10-year maintenance agreement.

MOZAMBIQUE Mega dam may displace thousands An estimated 1 400 families could be displaced by the Mphanda Nkuwa hydropower project due to be built across the Zambezi River in what would be Southern Africa’s largest dam.

Another 200 000 people could be affected downstream.

The government of Mozambique has touted the 1.5 GW Mphanda Nkuwa Dam, in the district of Marara, Tete province, as key for the Southern African nation to address energy poverty and reach its goal of universal energy access by 2030.

Both the World Bank, through its private investment arm – the

10 IMIESA March 2023

International Finance Corporation – and the African Development Bank are supporting the project and pushing for the dam’s construction.

At the end of 2022, Mozambique became Africa’s newest gas exporter despite 72% of its population having no electricity access. The Mphanda Nkuwa Dam is the country’s largest venture into renewable energy and is designed to supply power domestically.

The dam will be built in the lower part of the Zambezi River basin, around 60 km downstream from the existent giant hydropower plant at Cahora Bassa. Under current plans, the project is expected to reach financial close in 2024, with commissioning to start in 2031.

TRENCHLESS TECHNOLOGY | SEWER REHABILITATION COVER STORY

NAMIBIA Rural water development programme a success Under the programme, 20 shor t pipelines with maximum length of 20 km were constructed in several regions across the countr y.

Programme highlights included: • 141 boreholes were drilled.

• 2 877 private off-takers were connected to pipeline water supply.

• 53 boreholes/water points were installed.

• 3 575 existing water-supply infrastructures were repaired and maintained.

• 91 water-point associations were established.

Fur thermore, 625 communities were suppor ted with emergency water tanker ser vices, while 114 existing water-point infrastructure sites were rehabilitated, and 57 boreholes were cleaned and tested. Additionally, the Ondangwa-Omuntele water supply pipeline scheme in the Oshikoto Region was recently completed.

The Ministr y of Agriculture, Water and Forestr y, with funding from Disaster Risk Management, is currently extending the scheme due to the complexity of water-supply needs in rural areas. The contractor is currently connecting additional manifolds and water meters on the pipeline to provide water to newly identified beneficiaries. A pipeline network will be constructed to provide water to the communities in the Onamatanga area. An engineering consultant has been appointed and is currently developing the preliminar y designs.

ZAMBIA Solar to combat power outages The Riverside Solar Plant in Kitwe is a project of the Copperbelt Energy Corporation. The solar plant covers over 30 hectares, is split into two and comprises 61 300 solar panels, 150 inverters, six transformer stations and 4 km of transmission lines.

With an annual yield averaging 54.9 GWh, the plant will save 51 kt of carbon. At this capacity, the Riverside Solar Plant can supply 10 000 houses.

GHANA Plans for US$700 million gas processing plant The Ghana National Gas Company (GNGC) and its joint venture par tners have signed a project implementation agreement for a second gas processing plant (GPP).

The plant will be referred to as Train Two of the GPP (or GPP Train 2) and will have an initial capacity of 150 million standard cubic feet per day (MMscfd), expandable to 300 MMscfd.

Located at Atuabo in the Ellembele District of the Western Region, the plant will provide optimal capacity for Ghana Gas to process natural gas volumes in increments from the Greater Jubilee and Tweneboa, Enyera, and Ntomme fields.

It will be capable of processing natural gas liquids (NGLs) into their pure propane, butane and pentane components, which will then be stabilised into condensate components. The lean methane- and ethane-containing gas will be tied into the lean gas expor ted from the existing GPP Train 1 and sent to an onshore expor t pipeline. The purified butane and propane will then be stored in their respective storage tanks.

The plant will also have a storage facility, an additional compressor package at the Atuabo Mainline Compressor station, utilities and a liquid waste treatment system. It will contribute considerably to Ghana’s gas production, help its industrialisation and meet its energy needs by preventing power outages. Its construction will help create 1 000 jobs. About 90% of the gas will be used in fer tiliser production and the iron and steel processing industries.

The plant will also help to improve the liquid output processed from natural gas to 80%, compared to the existing 40-50%.

IMIESA March 2023

11

HOT SEAT

A pump leader for 71 YEARS and counting

Foremost, we’re an OEM. In addition to this, we are a Grade 8 contractor in terms of the Construction Industry Development Board rating system, providing turnkey civil, electrical and mechanical engineering services for clients in South Africa and Africa. A prime example in terms of the latter are the systems upgrades we’ve completed for Malawi’s Blantyre Water Board over the years.

Why is operations and maintenance (O&M) becoming a growing trend?

Optimal fluid transfer is central to all process industries – from water and wastewater to the petrochemical and energy sectors – and pumps are the driving force that makes this possible. IMIESA speaks to John Montgomery, GM for APE Pumps and sister company Mather+Platt, about the group’s innovative approach to ensuring sustained delivery.

What defines the group’s excellence as an OEM in pump design, fabrication and execution?

Seven decades in business is an exceptional track record. How has this been maintained and achieved?

JM The starting point is our rich history.

Mather+Platt traces its roots back to the late 19th century as a pump manufacturer that evolved with the First Industrial Revolution in England. Since then, Mather+Platt has been a forerunner in pump system product development. The same is true for APE Pumps, founded in 1952.

Both companies have led the market in terms of ongoing research and development for niche single- and multistage pump applications. Subsequently, we now also form part of multinational leader WPIL Limited.

Institutional knowledge is key. Every design drawing we’ve ever produced is on file so, irrespective of the date of manufacture, the group can either recondition or replace an APE or Mather+Platt pump from scratch. Plus, we have the in-house skills to execute this on a turnkey basis, with all materials sourced in South Africa.

We invest in our people, with a major emphasis on keeping them up to date with the latest technologies, and our personnel are proud to work for APE Pumps and Mather+Platt. A high percentage have long service with the group, which reinforces our commitment to long-term customer relationships.

Succession planning is another key focus, and we continue to recruit young qualified technical personnel at all levels to meet current and future requirements. This includes mechanical engineers, artisans and apprentices for specific trades that include fitters and turners, and patternmaking.

John Montgomery, GM, APE Pumps and Mather+Platt

12 IMIESA March 2023

How would you define the group’s business model?

There are various factors, but a key one is the cost optimisation benefits of outsourcing specialist skills to technology leaders that have decades of applied experience. OEMs are best equipped to enter into service level agreements (SLAs) – essentially O&M contracts – on their own systems.

For industrial clients, as well as municipalities and water utilities, the advantage is that these O&M contracts are entered into on a fixed-cost basis, plus it’s an off-balance-sheet solution for the client. Our pumps are maintained optimally during the warranty period for new installations, and for their indefinite life thereafter. We conduct regular performance tests to ensure that all our pumps run 100% to specification.

Currently, we have SLAs in place with leading public and private sector clients. As part of our commitment to excellence, we also provide training for our clients’ in-house technical teams.

How are O&M and asset management interlinked?

Every asset must be designed with a clear indication of its projected life-cycle costing and lifespan. That’s a primary concern for any asset owner because they need to budget for predictive and preventative maintenance. Asset investments should never be allowed to run to destruction due to a lack of maintenance planning.

Like any mechanically functioning system, best-in-class products need world-class service. They also require expert installation and optimisation.

Physical inspections are part of our SLA but – thanks to the latest developments in telemetry,

HOT SEAT coupled with the group’s purpose-designed apps – all our pumps can be condition-monitored remotely 24 hours a day. Process elements monitored include flow rate at a given head, bearing temperatures and pump vibration. In the unlikely event of an unscheduled incident, the pump can be set up to shut down automatically or via remote intervention, with a maintenance team sent to site.

We now also employ digital twinning during installation, where we can verify the virtual model of the final design against the physical system recorded via lidar scans. This allows us to cross-check, match and verify all elements during commissioning.

What’s the criteria for an SLA? SLAs can be concluded for brand-new group installations, as well as on our older systems installed years ago. In terms of the latter, we guarantee to restore these pumps – irrespective of their current condition – to OEM specification at a saving of around 60% of the value of a new pump. We then maintain them from there on. Upgrades, like variable-speed drives, also significantly improve energy efficiency.

A relatively small investment in an SLA definitely pays for itself by ensuring uninterrupted production, which is especially critical for water or wastewater utilities, or a power station. It’s all about having right the team onboard.

How does your pump service exchange work?

We have an extensive inventory of new and reconditioned pumps on hand. This enables us to swop out a client’s pump when it needs an overhaul and replace it with a new one during a

scheduled changeout operation. That provides major peace of mind for the client. We have also extended our facility in Germiston to house a full range of pump spares as backup for our extensive pump population and SLA clients in South Africa and Africa.

Is the group investing in new fabrication machinery?

Absolutely. New capex investments include an 8 m lathe with a 1.4 m swing. We now also have what we believe is the second largest key cutter in South Africa, as well as a new CNC horizontal boring machine, plus we’re investigating the acquisition of 3D scanners to further enhance our existing quality control systems.

We’re set up to do everything in-house. This extends from the design phase to the patterns, fabrication, machining, assembly, installation, alignment and commissioning.

What are some of the group’s recent and current projects?

We supply solutions for most of South Africa’s water and wastewater utilities on an ongoing basis, in addition to energy sector clients, plus industrial end-users.

A recent project example is a solution we provided for Transnet at Robinson Dry Dock in the Port of Cape Town. The dry dock has undergone an extensive refurbishment.

Our scope as an OEM was to supply replacement pumps, which have now been installed and commissioned. These successfully met the specification, as well as passing all the client’s tests on this critical facility, which is employed to refurbish local and international vessels.

Significantly, the new pumps were replacements for existing APE and Mather+Platt pumps that have been running at the dry dock for the past 60 years. As an interesting aside, most of the other dry docks in South Africa also run on our pump sets.

A current project is for Umgeni Water’s Hazelmere pump station, which supplies water to reservoirs in La Mercy and Verulam in eThekwini. Umgeni is currently upgrading the pipeline network capacity to meet future demand. To ensure optimum performance, our scope entails the installation of six APE pumps in total, all made in South Africa, which replace those installed previously by a French OEM.

And in closing?

Our longstanding reputation as pump innovation leaders is built on a solid foundation of experience, technology and a passion for developing fit-for-purpose solutions. Irrespective of the age of the thousands of APE Pumps and Mather+Platt pumps out there since 1952, we can restore them to pristine condition and keep them working optimally.

www.apepumps.co.za www.matherandplatt.com

IMIESA March 2023

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INDUSTRY INSIGHT

Steel pipes: THE BACKBONE OF

ANY WATER NETWORK

An industr y pioneer since 1924, Hall Longmore’s commitment to research and development continues to refine its class leadership in the steel pipe sector. IMIESA speaks to Kenny van Rooyen, managing director, and Callum Storar, contract sales manager, about the key role of steel in ser vice deliver y.

W

orldwide, steel remains the mainstream choice for bulk water conveyance, just as it did some 150 years ago, which underscores the performance benefits of this material to handle sustained high pressure rating requirements and variables like hydraulic shocks.

The introduction of advanced welding techniques in the 1920s presented a major breakthrough for steel pipeline integrity, further entrenching their place as the standard for water boards globally. Over time, the coating systems employed to combat corrosion and extend their lifespan have also improved significantly.

The general benchmark in the modern-day steel pipe manufacturing sector is to provide a 40- to 50-year design life once installed and subject to the fluids being transferred, such as water, wastewater, oil or gas. However, in Hall Longmore’s case, a number of their systems in the bulk water and mining sector have lasted for close to 100 years. Examples can still be seen in operation on some West Rand mines in Johannesburg.

Vital catalysts

Kenny van Rooyen, managing director, Hall Longmore

14 IMIESA March 2023

Callum Storar, contract sales manager, Hall Longmore

“Pipelines are often the unsung heroes in the infrastructure supply chain. However, they are essential catalysts for socio-economic growth, and the foundation for all current and future town and city master plans in terms of projected water demand – and we’re proud of our role as a manufacturer in engineering enduring infrastructure solutions,” says Van Rooyen.

“Steel pipes are futureproof, locally sourced and cost competitive. Plus, they also help to minimise non-revenue technical water losses

INDUSTRY INSIGHT

due to their robust composition. They are also climate-change resilient in the sense that steel pipes tend to withstand extreme weather, as was the case during the severe floods that hit Durban and surrounds in 2022. Once commissioned, it’s virtually impossible to pull steel pipe sections that have been welded together apart,” Van Rooyen continues.

“From our perspective, steel is the answer.

However, to make a sound business case, it’s important for municipal and water engineers to clearly understand the place and the designed performance characteristics for all alternative pipe materials available on the market, whether it’s GRP, plastic or concrete. Asset owners need to factor in the life-cycle cost and obtain the best possible return on investment for any product, technology or system employed. New contractors entering the market also need to be well informed.”

Examples of areas where steel pipe tends to outperform other materials include their ability to cope well with live and dead loads when installed under roads, in dolomitic conditions where subsidence is a risk factor, and in hilly terrain where there’s a greater risk of water hammer.

Widest possible choice Meeting the requirements of the bulk supply reticulation market, Hall Longmore manufactures medium-pressure pipes designed to operate within the 16 to 40 bar range, which makes them highly scalable in terms of current and future water demand coupled with network upgrades.

“What makes Hall Longmore unique in South Africa is that we produce pipe sections in the broadest possible spectrum in terms of diameters and wall thickness options,” explains Storar.

Manufacturing falls into two key categories, namely electric resistance welded (ERW) steel pipe and helical (commonly, but incorrectly, referred to as spiral) welded steel pipe, using the submerged arc-welding process (SAW). Hall Longmore’s standard OD range for ERW is from 219 mm (8”) to 610 mm (24”) and for SAW from 508 mm (20”) to 2 540 mm (100”). However, the nature of the helical process allows for bespoke diameters compatible to clients’ existing infrastructure.

“This manufacturing flexibility enables us to supply a complete town or city network, from

A section of Hall Longmore’s production facility in Wadeville, Gauteng

the initial bulk infrastructure to the progressive phasing in of the distribution infrastructure to meet ongoing residential and industrial expansion,” says Storar.

Outside the water market, Hall Longmore manufactures what are referred to as ‘oil country tubular goods’ (OCTG) pipes for the local and global petroleum and gas market. OCTG pipes must meet, and in some cases exceed, the requirements of the American Petroleum Institute (API) standards, considered among the strictest in the world for any sector. For these installations, there’s zero margin tolerated for ruptures, leakages or environmental disasters. “Clearly, this means that Hall Longmore’s quality control (QC) has to be world-class,” says Storar.

To further refine its QC processes, Hall Longmore recently invested in the latest automated radiographic testing (RT) technology. As per international standards, steel pipe manufacturers are mandated to employ RT technology for non-destructive testing on submerged arc welds.

The key difference now is that Hall Longmore has switched from analogue to digital X-ray techniques, which are far more precise.

Coatings Selecting the right pipe diameter and wall thickness is essential for optimum network

performance, as is the selection of the right corrosion protection method. Cathodic protection (CP) is common and it’s recommended that any proposed new installation be reviewed by a CP specialist As Storar points out, the internal and/or external coating system specified should always be determined following a detailed investigation by the client of the in-situ conditions. Factors to consider include the resistivity of the soil, as well as overhead powerlines and railway lines that emit AC or DC currents that may need to be countered cathodically.

“Hall Longmore is an industry leader in the technology and application of protective coatings and linings to steel pipes,” Storar explains, adding that the applications are tailored to suit the needs of specialist corrosion engineers.

Hall Longmore has the widest range of accepted pipeline coating and lining systems in the South African context. These include polymer-modified bitumen (PMB), fusion-bonded medium-density polyethylene (MDPE), three-layer polyethylene (3LPE) and rigid polyethylene (RPu) for exterior protection to underground pipelines subjected to highly corrosive conditions, and various liquid epoxy as well as cement mortar/concrete internally linings. The latter is a preferred

Traditionally, welded joints have dominated, but there’s a definite shift in the market to rubber ring joint applications.”

IMIESA March 2023

15

INDUSTRY INSIGHT Hall Longmore supplies a range of external and internal coating systems to match each site installation requirement

Hall Longmore’s RRJ system has been well accepted by the market, as there’s far less, if any, site welding required

lining medium for smaller-diameter (less than 610 mm) potable water services due to its ability to be reinstated at the joints without man access.

Couplings The Achilles heel for every pipeline – irrespective of the material composition, whether it be GRP, HDPE, steel or one of the other recognised pipe materials – is its joints, since they determine overall system integrity.

Within the steel pipe sector, there are numerous options available. Examples include welded, flanged, flexible couplings, bell and spigot (a secondary welded option) and rubber ring joint (RRJ) joints.

Hall Longmore’s RRJ system has been well accepted by the market as there’s far less, if any, site welding required. As a further plus, Hall Longmore provides training for contractors in the correct RRJ installation methodology.

“Traditionally, welded joints have dominated, but there’s a definite shift in the market to RRJ applications. One of the reasons for this is the steady decline of specialist welding skills in the construction sector. Time and cost are other key

factors, since RRJ couplings promote faster connection speeds without compromising the performance of the pipeline in any way on quality,” Storar continues.

The RRJ, in combination with a fit-for-purpose UV-resistant coating, is designed to perform for some 100 years underground and 50 years above ground. The RRJ system is suitable for steel pipes ranging from 300 mm up to 1 500 mm internal diameter.

Sewer systems While steel pipes dominate in the water sector, they are not the main option for wastewater.

One of the chief reasons is that sewer lines are predominantly gravity fed, negating the need for a pressure requirement to facilitate fluid transfer.

However, Hall Longmore does fabricate and supply niche solutions in wastewater, with

Fabrication of a helical welded steel pipe, using the submerged arc-welding process

16 IMIESA March 2023

examples including rising mains and pipe bridges. Since sewers are among the most corrosive environments, these pipe systems need to be internally lined with calcium aluminate cement (CAC), which tends to be costly but highly effective. Other alternatives for general industrial effluence include bitumastic polyphenolic epoxies.

Meeting SA’s development goals “It’s never a ‘one size fits all’ approach, since there are many variables to consider for each pipeline project. However, there’s a good reason why steel pipes are the benchmark for water utilities globally. And when it comes to service delivery, many South African communities trust steel because of its legendary durability to sustain infrastructure, with the demand for new pipe networks growing every year,” adds Van Rooyen.

“We’re standing by to deliver and are highly encouraged by the news that the South African government has allocated some R132.5 billion for water and sanitation in the 2023/24 and 2025/26 financial years. That’s a substantial investment, which will go a long way towards meeting the country’s commitment to providing safe drinking water and dignified sanitation for all,” Van Rooyen concludes.

www.hall-longmore.co.za

THE ULTIMATE Borehole Pump Controller An all-in-one solution that caters for all aspects of legislation, operation, control and monitoring.

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CONTROL ASPECTS Using variable speed drive technology, we are able to start the pump to the minimum speed as required, modulate the speed of the pump around a number of control conditions such as level in a tank or reservoir, pressure control and/ or flow control or constant level control of the ground water level.

MONITORING ASPECTS By monitoring borehole water level, pump discharge pressure, flow and anti-tamper -all available for remote viewing, this solution provides advanced monitoring tools for management, control and condition monitoring.

LOGGING ASPECTS All data is collected and stored securely in JOAT’s Hydralytix monitoring platform, to be used for condition monitoring and trend analysis, along with compliance and audit reporting.

For more information, contact: Tel: +27 (31) 700 1177 www.joat.co.za

Proudly EOH

BIENNIAL PROJECT EXCELLENCE AWARDS

CALL FOR ENTRIES To recognise outstanding achievements in municipal infrastructure, we are calling for entries

Planning and design Construction methods Innovation and originality

that showcase projects that demonstrate the best of civil engineering as a science and how engineering

Meeting social and technical challenges

enhances the lives of the local communities, through excellence in:

Contributing to the well-being of communities

CATEGORIES

1

ENGINEERING EXCELLENCE IN STRUCTURES & CIVILS E.g. Projects demonstrating engineering science, use of alternate materials, innovative construction processes, etc.

2

COMMUNITY UPLIFTMENT & JOB CREATION E.g. Projects demonstrating labour-intensive construction, skills development, community awareness/participation, etc.

3

ENVIRONMENT & CLIMATE CHANGE E.g. Environmental rehabilitation, renewable energy, drought solutions, coastal initiatives for rising sea levels, pollution control, educational/ technical initiatives, etc.

CLOSING DATE FOR SUBMISSIONS 03 July 2023

Only projects that have reached practical or substantive completion by 30 June 2023 will be accepted for the Excellence Awards.

Adjudicators reserve the right to reallocate entries in the 3 categories.

ENTRY FORMS AND AWARD CRITERIA Available for download on the website: www.imesa.org.za

IMESA THE INSTITUTE OF MUNICIPAL ENGINEERING OF SOUTHERN AFRICA (IMESA)

QUESTIONS Contact Debbie Anderson on +27 (0)31 266 3263 or email conference@imesa.org.za

ECONOMICS

INFRASTRUCTURE targets

At this year’s AfriSam Budget Breakdown event, Dr Azar Jammine, economist at Econometrix, highlighted key trends, stating that the R903 billion in public sector infrastructure expenditure earmarked for the 2023/24 to 2025/26 financial years is encouraging.

T

hese numbers are so big that if we were to see their full implementation, it would be a game changer not only for the construction sector, but for the entire economy,” said Jammine. “Where the real hope lies is in government getting its act together and starting to implement its capital projects.”

He noted the importance of how Minister of Finance Enoch Godongwana dealt with plans to restructure Eskom’s capital debt, as any worsening of the energy crisis could undermine the economic predictions in the 2023 Budget Speech. If load-shedding is exacerbated, Jammine said the country may not even reach its meagre 0.9% growth target for the year. In such a scenario, government’s own spending plans would be further dampened by lower tax revenues.

The question Jammine posed is whether there is the political will within the governing party to allow Eskom’s debt restructuring to take place. Such a move is inevitable, however, as he foresees a complete realignment of politics in the general elections of 2024.

Stimulating employment Focusing on the construction industry, Jammine once again painted a sobering picture, but highlighted the sector’s potential to deliver economic

and engagement

benefits. Currently, construction provides some 7.8% of the country’s employment, even though it makes up just 2.6% of GDP. “Implementing government’s infrastructure projects would spark massive job creation, and the economy could grow by 5-6% a year,” Jammine explained.

Commenting on Jammine’s presentation, Richard Tomes, sales and marketing executive at AfriSam, said “Although the operating environment remains challenging, one of the positive elements AfriSam has noted is the increase in the infrastructure spend budget allocation, and we remain hopeful that the implementation of the infrastructure projects will gain momentum and start delivering true value for the construction industry.”

Trading trends Industry data shows that considerable overcapacity is still evident in the nonresidential building sector, especially commercial office and retail space. This is subduing demand for new developments, with the

Dr Azar Jammine of Econometrix presenting at AfriSam's Budget Breakdown event in February 2023

Richard Tomes, sales and marketing executive at AfriSam

total value of non-residential building plans passed in 2022 hovering around the R1 billion mark, compared to R3 billion in 2016. The brief recovery in the residential building sector – as homeowners renovated for home offices – has also tailed off. Additionally, cement demand suffered negative growth in 2022 and is expected to improve only marginally over the next few years.

Rallying the sector “With many of us operating in the same industry, material matters such as the external environment we operate within not only relates to AfriSam, but also to our stakeholders’ businesses,” added Tomes, explaining the rationale for the annual AfriSam Budget Breakdown event.

“We hope that the information being shared will not only provide them with insight about some of the decisions that AfriSam takes, but will also provide them with valuable insights to enable decision-making in their own businesses or organisations to ensure their future success and sustainability,” Tomes concluded.

Jammine’s full presentation can be downloaded at www.afrisam.co.za/ budget-breakdown-2023.

IMIESA March 2023

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WATER & WASTEWATER

Digitalisation was used in the design workflow and in the Mhlabatshane BWSS project for Umgeni Water

Naidu Consulting has grown exponentially – with water and sanitation projects having played a fundamental role. The consulting engineering firm has a vision of becoming a leading service provider of quality, economic and innovative engineering solutions.

Diversification in an evolving sector

T

he chairman of Naidu Consulting – Selvan Naidu – spearheaded the formation of the Water & Sanitation Division through the designs and implementation of various projects within eThekwini Municipality, which included multiple reservoirs, reticulation systems and bulk water supply systems.

Among the largest projects undertaken by the Division were the Western and Northern

Aqueducts in eThekwini Municipality. These projects sparked the growth of Naidu Consulting’s Water & Sanitation Division, which boasts a diverse range of skills,” explains Terence Thumbaya, Head of Division, Water and Sanitation,

Diversification of skill sets Thumbaya adds that the Division’s focus is to ensure it provides innovative and

When increasing the storage at the Shongweni Reservoir, Naidu Consulting together with the contractor, sponsored the local soccer team with new soccer gear, which included complete kits, a soccer ball, bag and whistle

20 IMIESA March 2023

sustainable solutions throughout the project life cycle. This is done with highly skilled and experienced professionals who provide a consistent level of the highest-quality service and unique personal attention to its clients.

The combined expertise and knowledge in the Water & Sanitation Division allows Naidu Consulting to cover a spectrum of services within the various disciplines.

Ashveer Goorun, Sector Manager: Water & Sanitation Division, notes that, in South Africa, there has been an emerging emphasis on water-loss management and water conservation. “Our skill set around pressure management and non-revenue water has evolved through the implementation of successful non-revenue water contracts.”

Goorun adds that Naidu Consulting also has an in-house, registered, Approved Professional Person who specialises in hydrological studies and dam designs up to Category II dams. He explains that water security is a key priority among many of Naidu Consulting’s clients and ageing infrastructure poses a threat to the sustainability of water supply systems. “As a result, Naidu Consulting has reinforced itself as a company that can provide value-added services in asset management, non-revenue water and water conservation.”

Due to climate change and global warming, stormwater management must be

WATER & WASTEWATER considered in the design or construction of any infrastructure, especially in light of recent flooding. “Our team has played a significant role in the assessments, repairs and replacement of infrastructure that was damaged during last year’s floods in KwaZulu-Natal. One of the most notable projects was the repair of the Tongaat Water Treatment Works within 105 days. In addition to that, we have been assessing culverts, bridges, stormwater systems, as well as flood lines for high-value assets,” states Goorun.

Digital transformation is another skill set that Naidu Consulting continues to embrace and develop. “The Water & Sanitation Division has, over the last few years, successfully introduced digital design into our project workflow. This was illustrated in the proposed Mhlabatshane Abstraction Works where a digital twin was created for Umgeni Water. The next digital initiative in the Water & Sanitation Division is exploring the practicality of augmented reality. Global trends show the use of this technology to take the projects team from the office environment to site locations with the use of readily available smart devices,” explains Thumbaya.

ESG He adds that the Division strives to apply the environmental, social, governance (ESG) principles throughout a project’s life cycle, Among the largest projects undertaken

by Naidu Consulting’s Water & Sanitation Division were the Western and Northern Aqueducts in eThekwini Municipality

WATER AND SANITATION PROJECTS Western & Northern Aqueducts The Western Aqueduct is the single largest water infrastructure project undertaken by eThekwini Municipality. It brings water into Durban from the Midmar Dam and Spring Grove Dam, providing additional ultimate capacity of 272 Mℓ/day of water.

For Phase 2 of the Western Aqueduct project, Naidu Consulting was responsible for the design of 18.4 km of pipe (DN 1 400 and DN 700) and contract administration and construction super vision for 34.1 km of (DN 1 600 and DN 700) continuously welded steel pipeline. This included the transient analysis for the entire Western Aqueduct Phase 2 bulk water system.

Owing to the rapid expansion of residential, commercial and industrial developments in the northern regions of Durban, eThekwini Municipality initiated the Northern Aqueduct Augmentation project. Naidu Consulting was responsible for the design, contract administration and construction supervision of 20.5 km of DN 1 200 and DN 600 steel pipe.

Mhlabatshane Bulk Water Supply Scheme (BWSS) Digitalisation was used in the design workflow and in the Mhlabatshane BWSS project for Umgeni Water, where a digital twin of the river abstraction works was developed – allowing for enhanced design efficiency and, ultimately, reduced environmental impact.

which enables the project team to ensure quality, risk management, community outreach and social facilitation. eThekwini Municipality’s Water and Sanitation (EWS) Unit identified within its bulk reservoir supply network the need to increase storage at the Shongweni Reservoir site, which is supplied from the existing Georgedale Reservoir. The works under this contract consisted of the construction of a 6 Mℓ reinforced concrete reservoir with ancillary pipework.

In accordance with Naidu Consulting’s ESG initiatives, the community within the corridor of the infrastructure upgrade was assisted with the following: • The construction of a creche had halted due to not having building material.

Naidu Consulting, together with Robin Hood Foundation, donated M140 concrete blocks.

• The local soccer team was sponsored with new soccer gear, which included complete kits, a soccer ball, bag and whistle.

• Victims that were affected by the 2022 KwaZulu-Natal floods were housed in Shongweni community hall.

They were supplied with gas, food, blankets and mattresses.

diversified outside of South African borders by providing professional design services to entities within Lesotho and Mauritius. With a diverse client base in both the public and private sector, the Water & Sanitation Division continues to strive for diversification.

Thumbaya states that Naidu Consulting’s growth has come from a dynamic team comprising a broadened skill set and the ability to adapt and meet clients’ expectations. “The water and sanitation sector requires a broad range of expertise to work on an assortment of projects – from bulk water supply, treatment and distribution to dams, stormwater and sewer infrastructure.”

Rather than dwelling on the problems that constrain infrastructure delivery, Goorun believes in creating value-engineered solutions that work. He also believes that future engineers will have to respond quickly to challenges. “The emphasis is on getting the job done, on time and on budget, and bringing the community on board at all stages. It is an exciting time for young engineers to join the water and sanitation sector, and increase their expertise on a variety of projects.”

Growth With Naidu Consulting’s head office located in KwaZulu-Natal, the company has grown in size and expanded its local footprint to the Western Cape, Eastern Cape and Gauteng regions. Naidu Consulting has also

www.naiduconsulting.com

IMIESA March 2023

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GROUNDWATER

Making rural water supply more sustainable Standalone water supply points in rural areas are vital to the schools, clinics and communities they serve, but the systems are often not functional, says Gert Nel, principal hydrogeologist and partner, SRK Consulting. He suggests some ways to make progress.

N

el highlights that these rural supply points – located in areas that cannot be reached by bulk water supply – number in their thousands. The schemes usually include one or more boreholes as a water source, with a pipe network for water distribution and a water treatment system typically comprising a filter and chlorinator.

“Where these systems are installed for a school, for example, there is often a few months’ supply of chlorine that is provided at the outset – to be manually applied by the

users,” he says. “In my experience, however, there is seldom any backup support or funding to ensure that these water supply initiatives are sustainable in the medium to long term.”

Funding and training The key issue is usually that the school is not equipped or funded to adequately manage their groundwater source. There is no proper training by suitably qualified people on basic groundwater management, for instance.

“If the water stops flowing, there is seldom anyone available with the necessary experience to establish what the possible causes could be, and to know how to resolve them,” he says. “It could be that the water has dried up due to overpumping and lack of water-level monitoring – or there may be an electrical fault.”

Chlorine availability, load-shedding He notes that there may also be quality issues to monitor and address. Many remote rural areas struggle to secure new supplies Gert Nel, of chlorine once the initial stock is principal hydrogeologist depleted. Local hardware stores in these and partner, areas may not always have stock, and SRK Consulting delays can create water quality risks for the users.

“Lack of reliability of the electricity network – and regular load-shedding – exacerbates these challenges,” says Nel. “Water storage tanks are generally designed to work with a permanent water flow so, when energy outages stop the pumps

from working, there is often insufficient water available. The operation of water treatment systems may also be disrupted by load-shedding.”

Compounding the issue is the high rate of crime in many of these areas, which affects communication, among other things. Battery backup systems for cellular phone masts – and the solar panels that recharge them – are often stolen. With the cellular connection being disrupted, it takes longer to report and resolve issues with the water supply points.

Recommendations In terms of the steps that could be taken to make rural water supply points more sustainable, he suggests that the tenders for these contracts should include aspects relating to training, awareness raising, mentoring and ongoing support for the water users. In a school environment, there could be a valuable ‘teaching moment’ for explaining the basics of groundwater management – for both teachers and learners. By understanding their groundwater source and potential challenges, they can plan ahead and mitigate most of these challenges.

“It is also vital that the water authorities understand more about the challenges that users experience on the ground, so more research and investigation is certainly necessary. Such a process will help inform sustainable solutions, including social, educational and technical support elements,” Nel concludes.

IMIESA March 2023

23

PERFECTING SOUTH AFRICA’S WATER NETWORKS

Scientific ways to carry out water master planning and execution

Harnessing the power of its proprietary software suite, GLS Consulting leads the municipal engineering market as a water, sewer and electricity modelling and master planning consultancy. IMIESA speaks to Adie Vienings, head: Business Development, about the company’s unique approach to planning and how to get it right the first time when it comes to water networks.

Infrastructure planning for large towns, district municipalities and metros seems an overwhelming and daunting task. Is it really possible to see the future and plan for it?

AV Yes, it is. Thanks to today’s advanced engineering software programs, water network designers have high-tech tools at their fingertips to simulate and model captured data for future planning scenarios. Of course, the accuracy of the information is fundamental to the process, which is why engineers must always first know what exists in the physical domain. That starts on the ground with cadastral survey verification.

All proclaimed stands in South Africa are maintained by the Surveyor General. And these

24 IMIESA March 2023

stands can be verified with aerial images superimposed on their cadastral survey maps and cross-checked by linking this information to municipal billing data.

Then there’s the existing municipal water and sewer network, which must be supported by an up-to-date asset management register, coupled with a predictive and preventive maintenance programme.

That’s the ideal, and the legislated requirement. However, the format in which these water networks are monitored and recorded by municipalities at present can vary from something basic like a screen shot to more

sophisticated formats such as CAD or GIS – the gold standard being hydraulic model formats.

So, known network performance must be determined up front, because that heavily influences what needs to be achieved to execute each municipality’s Spatial Development Framework (SDF) plan in terms of residential and commercial expansion.

Engineers utilise this town planning information to virtually extend existing water infrastructure into all these proposed development zones. They then determine the best locations for new water and wastewater treatment plants, pipelines and reservoirs. That groundwork further determines how much the network will cost to build and maintain.

Tables of unit costs are established for pipelines (diameter, per metre, material), treatment works (per Mℓ/day) and pump stations (flow rate and head). These tables also factor in provincial cost differences.

Using our hydraulic modelling software, the total budget required per suburb to be developed, with a corresponding drawing, is available at the click of a button. These reports generated from the software are used to guide investment by the municipality and developers.

Is sufficient information available and from where is this sourced?

With historical meter reading data, the average unit water demand per land use category – such as housing, industrial, commercial, educational, and recreational – can be determined and used to inform future planning. Some of the most crucial information comes from the as-built drawings.

ECSA’s Guideline of Professional Fees outlines ‘Normal Services’ and breaks this down into six clear stages. Stage 6 is the Close-Out stage, at which completion certificates, manuals,

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As-built drawings record all infrastructure sizes, location, material details and heights above mean sea level

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What makes GLS’s software a game changer?

Our unique solution has set a new benchmark by integrating hydraulic mathematical modelling,

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The key challenge for network planners is that it’s not uncommon to receive less than correct as-built drawings. And for older networks, there are times when the plans have been lost, and situations where ageing infrastructure installed decades ago has been ‘forgotten’, with no modern-day record of their existence.

Accurate as-built data is essential in establishing holistically complete asset registers and lends itself to the development of the evolving hydraulic model. This is because the hydraulic model contains databases of all infrastructure. For example, there is a shapefile and database of all reservoirs with their attribute data, such as year commissioned, replacement value and broad condition assessment (index from 1 to 5).

Likewise, the database of pipelines can be exported from the hydraulic model and summarised using any field in the database. As such, the data summary report types are almost endless – e.g. total pipe length and cost by diameter, total infrastructure replacement value per ward, comparative graph of infrastructure older than 40 years per suburb, etc.

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CAD drawings and GIS capabilities to form a complete selfcontained toolkit for water network planners. This enables seamless integration of data from all sources, including imported jpegs and aerial photos, all while working on a single platform.

In terms of recent developments, the software has been extended to include features that allow for rapid population of large models with unit water demands, linking of unit costs to all future infrastructure, generation of plan book pages, and generation of master plan reports in a relativity short space of time. GLS has also collaborated with other technology partners to display the water network of a town in a view-only format and online, similar to seeing features in Google Earth.

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guarantees, final accounts and as-built drawings must be submitted.

As-built drawings record all infrastructure sizes, location, material details and heights above mean sea level. This information is vital for producing real-world hydraulic models that calculate actual and theoretical network performance. With additional engineering tools, the adequacy of existing reservoir sizes and pump sizes can be determined. Areas with ageing infrastructure can also be displayed visually in the software using the captured information of pipe age, material and remaining useful life.

For the modelling process to work optimally, municipal as-built drawing registers should go back as far as possible – ideally to the original plans, some of which might be well over 100 years old in the case of older towns and cities.

PERFECTING SOUTH AFRICA’S WATER NETWORKS

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the water network over an extended period of balancing the models • train O&M staff to access the plan book pages of a specific area of the water network on the internet, so they know the location of pipes, values and all attribute data when in the field • use all the base data obtained for water planning to then do sewer, electrical and stormwater planning • train municipal officials to utilise the GLS software.

And in closing?

Where has GLS’s model/approach worked best in practice?

The municipalities that have got the best value out of perfecting their networks are those that have used their models as a basis to other services. From the asset register and models, some municipalities have gone further to: • determine the cost of supplying the water service over time, including operations and maintenance (O&M) • determine water losses in the municipal system and revenue being lost through unbilled consumers • compare scenarios of rand value investment each year (low to high) to replace older pipes versus the increased cost of pipe repairs for pipes only replaced in later years (referred to as multiyear pipe replacement programme studies) • test required fire flow volumes (say 50 ℓ/s or 20 ℓ/s) at hundreds of strategic points in

With well-established hydraulic modelling software, 30 years of experience in master planning, a competent team of civil and electrical engineers, and the completion of master plans for over 60 municipalities in South Africa (and abroad), GLS has found perfecting our country’s water networks – from a planning point of view – to be a real professional challenge and exciting.

Going forward, GLS is committed to serving municipalities and South Africa with this state-ofthe-art service offering.

www.gls.co.za

IMIESA March 2023

25

INSTRUMENTATION

All-in-one, adaptable flow meter Thanks to its flexibility, the H250 M40 can be adapted to any application

For over a centur y, Krohne has been producing variable area (VA) flow meters. The company’s latest product is the H250 M40, a standard VA flow meter for the process and OEM industr y.

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ombining the mechanical flow measurement of liquids or gases with communication capabilities, the H250 M40 is modularly extendable. Additional electronic modules can be added or replaced at any time without process interruption.

In this way, its functionality adapts to new requirements – from analogue flow measurement without auxiliar y power to

digital integration into a fieldbus system.

Certain variants of the flow meter with limit switch or analogue output are suitable for use in safety instrumented systems. Electronic device diagnostics and additional application diagnostics are available to increase application reliability.

For instance, it can report on the detection of a float blockage due to impurities or pressure surges and the reporting of pulsating flow or gas compression oscillations of the float.

Robust design Krohne H250 M40 flow meter

26 IMIESA March 2023

The H250 M40 is explosion-proof, and available in various materials. The all-metal flow meter can be also used in applications with high pressures (up to 1 000 bar), temperatures (-196°C to 400°C) or aggressive media. There is also a special version for use in hygienic applications.

The measuring principle allows for a robust, closed-tube design without sensor feedthrough, as the height of the float is transferred to the indicator by way of a magnetic coupling. This enables high-pressure versions that can withstand up to 900 bar.

All wetted, pressurised parts are made as standard of 1.4404/316L and 1.4401/316 dual-certified stainless steel and meet the requirements of the NACE MR0175/MR0103 standard.

To guarantee the longevity of the device, even with chemically harsh products, it is possible to use special materials such as Hastelloy®, titanium, Monel®, 6Mo and Inconel® in production. In addition, the H250C M40 is also available with a PTFE liner for applications involving aggressive acids and bases.

With the indicator housing made of stainless steel, the H250 M40R withstands attacks from salt fogs and contaminated precipitates. It can be reliably used in corrosive atmospheres and is per fectly suited for use in spray water zones, such as in the food and beverage industries.

Unique to date: the indestructible stainlesssteel housing is also available on request in an explosion-proof version for use in hazardous areas.

As a high-temperature variant, the H250 M40HT measuring device is suitable both for ver y high product temperatures up to 400°C, as well as cr yogenic applications down to -200°C. The increased distance between the measuring tube and the display makes it easier to insulate the measuring tube.

Typically, VA flow meters are installed vertically in rising pipes and the product must flow through them from bottom to top. This can lead to considerable expense.

The H250 M40 measuring device on the other hand offers you freedom in terms of design as unique versions can be used for horizontal or even descending pipes.

WORLD WATER DAY

If the world were 100 people It is difficult to visualise the global water and sanitation crisis. Facts and statistics are important but can be impersonal. So, what would it look like if we applied the global water and sanitation crisis to a community of just 100 people?

25 people would have to collect unsafe water.

22 people would have no

22 people would either work in, or receive care at, a healthcare facility that has no basic water service, placing them at heightened risk of infectious diseases.

choice but go to toilets in the streets, bushes or fields, or to use unhygienic and dysfunctional latrines.

The water would usually be far away or they would have to pay a high price to a vendor.

The water would regularly make them so sick they couldn’t go to work or school.

Death from entirely preventable diseases, like cholera and typhoid, would be a constant danger.

Women and girls would suffer most, as they would be more vulnerable to abuse and attack, and unable to properly manage their menstrual health.

46 people would live in areas vulnerable to disease because their wastewater and faeces flowed back into nature without being treated.

Many of those will be receiving treatment for diseases that could have been prevented with safe in the community.

WATER DEMAND MANAGEMENT & WATER SECURITY

MAGNETIC WATER METERS SAVE UTILITIES MILLIONS The key purpose of potable water meters is to measure, and charge for, all billable consumption. A second benefit of accurate meters is that water balances reveal water losses caused by technical factors like leakages and illegal connections. The accuracy of these meters is therefore vital for the financial viability of water service providers.

Mechanical meters are calibrated by positioning a vane that adjusts the water’s angle of impact on the propeller blades. Pebbles wedged in the meter’s input structure will play havoc with the angle of the water flow and severely affect accuracy

power grid outages – and as a result, watershedding. In other words, power interruptions disrupt water treatment plant operations, pump stations go down where there’s no dedicated genset backup, and water delivery suffers. Intermittent supply and the resultant pressure surges can in turn have a direct impact on metering accuracy if the right technologies are not installed,” Bosman expands.

The cost of underreading

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any municipalities and utilities still use mechanical meters to record these flows – as they have for many decades – but the evidence shows that magnetic meters are far more accurate,” says J-P Bosman, from N&Z Instrumentation and Control.

A key characteristic of mechanical meters is that they tend to underread over time due to their inherent design. In addition to normal wear and tear, the impellers that rotate to measure flows within the pipeline often sustain damage or break off due to debris impacts, like pebbles, which also cause blockages and jamming. This scenario can be exacerbated by air slugs that cause the meter to overspeed, further resulting in impeller damage causing the meter to underread.

“Plus, there’s load-shedding – South Africa’s popular term for sustained daily

28 IMIESA March 2023

Even in relatively conservative cases where a mechanical meter underreads by 5%, the value of underbilled water is still substantial.

In a typical scenario, a meter installed in a 200 mm internal-diameter water pipe could underbill by some R85 000 per month – and for an 800 mm pipe, underbilling could easily be R1.3 million per month!

From a life-cycle costing perspective – and based on a wholesale price of water of R12/m3 – these figures are even more alarming when projected over a 12-year period. In this example, an accurate

200 mm meter should typically bill over R234 million and an 800 mm meter a staggering R3.7 billion. However, the retail mark-up (the tariff a municipality adds on after buying the water from a water board) could increase these values by 70%.

“The point to emphasise is that substantial revenues that should be billed continue to be lost, negatively affecting municipal budgets and available funds for current and future routine maintenance and infrastructure upgrades. Imagine eliminating the losses,” Bosman notes.

Magnetic versus mechanical The reason why magnetic flow meters provide utilities and municipalities with far greater certainty is due to their unparalleled accuracy. Unlike their mechanical counterparts, magnetic flow meters have a completely open bore, so they are not subject to any of the wear and tear scenarios common among their mechanical counterparts.

“As part of our market offering, we provide flow survey services to municipalities and utilities to help them optimise their system,” Bosman continues. “The technology we employ here is ultrasonic sensors, which are placed on the exterior of the pipeline being measured.

“We record the accuracy of the client’s meters and issue verification certificates.

In most cases, the client will accept an error of 5% either way in terms of over- or underreading. Our experience from many flow surveys shows that only around one third of mechanical meters are within this 5% accuracy band. The rest are often startlingly inaccurate.”

WATER DEMAND MANAGEMENT & WATER SECURITY

ADVANTAGES OF MAGNETIC FLOW METERS - Not prone to underreading - Typical accuracies of ±0.5% - A wider flow range - Automatic remote meter reading on a daily basis - Built-in verification on an hourly basis - Measure flow total, flow rate, line pressure and reservoir level with the same meter

Having established the business case, a high percentage of clients switch to magnetic meters, where the downstream benefits are immediate, following the installation. This is because N&Z’s battery-powered flow meters and

web-based information system enhance both accuracy and productivity. No one has to be sent out to read N&Z’s magnetic meters.

Automated and highly accurate Connected via GSM modems, magnetic meters communicate their recorded data 24/7, powered by a lithium battery that generally lasts for three to seven years thanks to energy-efficient electronics.

Mechanical meters damaged by stones and debris resulting in severe underreading A selection of magnetic flow meters designed for varying internal pipe diameters.

The batterypowered meter is unobstructed and the same size as the pipe, so it is immune from damage, fouling or blockages, which are so common with mechanical meters

In addition, an in-built verification system continues to monitor meter performance hourly to confirm it is within tolerance.

Data is transmitted, downloaded, analysed and interpreted via a WaMSS Scada hub, with automated reporting in real time based on standard and/ or preset parameters via the WaMSS Scada. Examples of reporting parameters include monthly water losses versus water billed, water treatment plant inflows and outflows and water loss, day and nighttime flow patterns, line pressures, as well as reservoir levels. Tariff data can in turn be exported to any accounting software program in use by the client.

“A mechanical meter only records one metric and that’s the volume of water through the pipe,” says Bosman. “Compare that to our magnetic meters, which record 96 metrics daily with a metering accuracy of ±0.5%. Clearly, this enables unparallel system control for utilities so they can troubleshoot problem areas and fix defects like leakages that exacerbate their financial losses. This is in addition to accurate billing without underreading.”

N&Z installed its first magnetic flow meter around 2008 for Gauteng-based utility Rand Water. Since then, more than 900 units have been installed nationally for public and private sector clients ranging from municipalities to manufacturers and mines.

“Clearly, the bigger the pipeline, the more the rand value is magnified and here the smallest gains translate into huge savings in lost revenue, plus the unnecessary technical losses that our water-scarce country can ill afford,” Bosman concludes.

www.nz.co.za

IMIESA March 2023

29

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WATER DEMAND MANAGEMENT & WATER SECURITY

How do we fix SA’s critical

water challenges?

South Africans have a constitutional right to water, and our society has made substantial gains since 1994 to meet that right. But we’re also a water-scarce country and face several severe water challenges.

By Chetan Mistry

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s a nation, we have very high water consumption levels – 235 litres per person daily, well above the world average of 185 litres. And rapid urbanisation is adding significantly to that consumption rate and placing pressure on available services.

Since 2016, for example, Gauteng has grown by at least a million people, and the Western Cape's population has increased by 79% between 1995 and 2018. Yet neither region’s infrastructure has kept up, nor have other places, with experts estimating that only a third of South Africa’s water infrastructure is operational.

Failing water infrastructure results in significant financial losses. Over 40% of water piped by local municipalities (around 70 million litres per day) doesn’t reach its destination, costing local economies more than R7 billion annually. And while we worry about the rising electricity costs, water costs are outpacing those and have increased 1 270% since 1996, compared to 1 120% for electricity tariffs.

particularly at schools and among communities.

The more local people become custodians of their water supply, the more they will protect it. Part of that process is to popularise water tanks, rainwater capture, and recycle greywater to sustain gardens, household activities, car washes and numerous other uses.

Such good habits can extend into different industries. Water’s rising cost makes efficiency a priority. Fortunately, modern water technologies are up to the challenge.

Farmers can invest in improvements such as drip irrigation and create mini earth water breaks to prevent excessive run-offs.

Mining and manufacturing groups can recycle water and use data analytics to reduce water costs and wasteful consumption.

How the water industry helps Water technologies and their ecosystems play a big role in supporting public infrastructure.

Fixing SA’s water There isn’t much we can do about droughts, but we can hugely improve our water efficiencies.

On an individual level, we can save a lot of water through water awareness education,

Chetan Mistry, strategy and marketing manager, Xylem Africa

A prime example is the deployment of advanced leak detection systems. Infrastructure is also being revitalised, a case in point being efficient and environmentally friendly UV sanitation upgrades to Cape Town’s Strandfontein Wastewater Treatment Works.

Yet we can do more. Many cities and towns cannot keep up with water infrastructure’s skills and financial demands. The water industry can provide affordable access to equipment through rentals and repairs, and reduce costs by manufacturing some components inside the country. We can also help to stem non-revenue water losses.

Our partner networks have many skilled professionals who can collaborate with local municipalities, helping them fix immediate problems, recoup financial losses, and retrofit older sites with new, efficient enhancements.

South Africa has the tools to address our water challenges. We can create a future where people don’t have to walk kilometres to find a working tap, towns make reliable revenue and the state meets its constitutional promise that everyone deserves access to water.

IMIESA March 2023

31

WATER DEMAND MANAGEMENT & WATER SECURITY

The two recurring extremes -

DROUGHTS AND FLOODS

Ser ving its members and the industr y at large, IMESA is playing an instrumental role in driving awareness and understanding on key issues affecting the municipal landscape. Alastair Currie speaks to Professor Kobus Du Plessis about two current initiatives being rolled out in response to pressing factors that include climate change, urbanisation trends and future geospatial planning.

Professor Kobus Du Plessis, Stellenbosch University

32 IMIESA March 2023

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ducation and training are two of IMESA’s primar y mandates to ensure the highest levels of professionalism in the municipal engineering space, frequently working in conjunction with industr y stakeholders.

A prime example is the development of A Water Reclamation and Reuse Guide for South African Municipal Engineers, launched in September 2022. This initiative is a joint effort between IMESA and the Water Research Commission (WRC).

In parallel is a second key endeavour led jointly by IMESA and the WRC to establish a ‘Best Practice Guideline for Design Flood Estimation in Municipal Areas’, working with specialist engineering practitioners, as well as the University of the Free State, the University of KwaZuluNatal, and Stellenbosch University. As part of the process, the WRC established a reference group to peer-review the guideline’s contents.

Both initiatives are part of a bigger picture where climate change has induced severe weather pattern extremes, like regular and extended droughts, plus unprecedented levels of flooding. Research in the latter area is being driven at national level by the National Flood Study Programme (NFSP) Task Team.

“Floods pose a threat to society in general, our infrastructure and a sustainable economy, and clearly the provision of safe drinking water and dignified sanitation is non-negotiable,” explains Du Plessis, who specialises in the field of hydrology and environmental engineering at Stellenbosch University, as well as ser ves on a voluntar y basis as IMESA’s technical director for training and skills development.

Flood mitigation As in many other developing nations, the major shift from rural to urban centres has tended to over whelm South Africa’s

Delegates attending IMESA’s workshop in Johannesburg on the new water reclamation and reuse guide for South African municipal engineers

WATER DEMAND MANAGEMENT & WATER SECURITY

existing infrastructure ser vices, as well as available formal housing, resulting in a massive surge in informal settlements, which in Gauteng alone number around 700, some within known floodplains.

Coordinated town and regional planning is key to addressing these as well as a myriad of other interrelated challenges that include effective stormwater management to counter the increase in hard run-off areas spurred by new residential and commercial developments.

From an engineering perspective, the best response depends on having the right level of internal capacity within municipalities.

“The metros tend to be better stocked with experienced professionals, but for smaller local municipalities this is often not the case,” Du Plessis explains.

“At present, our obser vation is that the bulk of the work within smaller municipalities is being per formed by

consultants and that municipal officials are generally not well informed enough to ask the right questions. This was the objective for the development of the best practice guideline, encouraging municipal engineers to adopt a proactive approach, and to red-flag areas of potential concern

Stuart Dunsmore, managing director, Fourth Element Consulting (left), and Professor Kobus Du Plessis engaging with delegates on the progress of the ‘Best Practice Guideline for Design Flood Estimation in Municipal Areas’ at the IMESA Conference 2022

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WATER DEMAND MANAGEMENT & WATER SECURITY

in assessment reports presented by consultants,” Du Plessis continues.

In terms of South Africa’s National Water Act (No. 36 of 1998), flood lines must be indicated on all plans for the development of townships. Based on hydrological modelling, these typographical elevation lines indicate the extent of the typical 1:100-year flood events, demarcating the areas where future spatial planning can take place outside identified flood risk zones.

Keeping data up to date A lot of the available data on design flood estimation dates to the 1970s, so the guideline also ser ves to validate and update essential information gaps. That’s especially important as flood lines have a limited time span and are dynamic. Given the variabilities of climate change and development options, they could change in five to ten years’ time, so a full catchment approach is required.

“It’s a moving target and the guideline reinforces the expert knowledge needed to model and determine flood lines for towns and cities, with a step-by-step process outlined. We further emphasise the crucial need for local authorities to have appropriate by-laws in place to prevent residential or commercial development (formal or informal) within demarcated flood hazard zones,” Du Plessis continues.

The Cape Town Water Reclamation and Reuse Guide workshop

The guideline is intended to complement existing industr y documents, like Sanral’s Drainage Manual, drawing attention to existing workable methodologies in use.

The IMESA guideline also highlights and includes new applied research on condition that it has already been published in a recognised, peer-reviewed journal.

Within the guideline, there are quick reference links to websites on input parameters needed for flood calculations, which include rainfall, soil characteristics and elevation models. These and other elements must be incorporated to establish a flood line calculation based on the catchment in a specific area. In this respect, the guideline presents various recommended flow calculation methods.

On 17 February 2023, the guideline in its current form was signed off by the technical reference group and has now been referred

to the WRC for finalisation. The final release date is scheduled for mid-year. Thereafter, IMESA, with the support of the WRC, plans to run training workshops nationally.

Reuse and reclamation Within its holistic approach to knowledge sharing, IMESA understands that, when it comes to water and its availability, nothing functions in isolation. Wastewater treatment plants need to process effluent to strict standards before releasing it – typically into rivers for downstream abstraction and reprocessing by other utilities to produce potable water.

That’s a conventional take on reuse, but South Africa’s pressing water scarcity threats demand a fresh approach, mirroring countries like Israel. The latter currently processes some 85% of its wastewater for reuse in applications that include

Hartenbos delegates

34 IMIESA March 2023

WATER DEMAND MANAGEMENT & WATER SECURITY

The Bloemfontein Water Reclamation and Reuse Guide workshop

agriculture. So why is South Africa not doing something similar?

“The IMESA reuse guide is not purely there to address the shortage of water. There are direct and indirect benefits. An example is the deferment of the capital cost to upgrade a water treatment facility, and the ensuing additional energy cost savings. Plus, from a sanitation perspective, South Africa needs to address the massive wastage caused by flushing loos with potable water,” Du Plessis explains.

Consumers need to understand the crucial value of water as a finite resource, which is often taken for granted. This goes hand in hand with environmental stewardship, such as ensuring the sustainability of wetland systems that naturally scrub out harmful pollutants like heavy metals.

By choice or necessity – the journey to implementation Countries as diverse as Namibia and Singapore have had to embrace reuse out of necessity and have successfully achieved this by educating end-users up front about the technologies that make it safe and

effective. As Du Plessis points out, a ‘toilet to tap’ perception of reuse methodologies is obviously not going to work. Communities need to know it’s safe.

“Our interactions have shown that some municipal officials view wastewater reuse as too technically challenging, which it isn’t.

Some also consider that reuse is something for the future. However, that future is now.”

The purpose of A Water Reclamation and Reuse Guide for South African Municipal Engineers is to dispel these perceptions and to demonstrate those approaches that work best. As with the Israeli example, the immediate benefit is that reclaimed wastewater can be used for industrial processes, rather than potable water, lowering municipal process costs. In this respect, the guide touches on funding and financing for reuse schemes.

IMESA launched the first workshop in November 2022 – a day ahead of the IMESA annual conference in Johannesburg. The first one for 2023 kicked off in Bloemfontein in January, followed by workshops in Cape Town, Hartenbos and Gqeberha, with a final workshop due in March in Durban.

“The message we bring across is that reuse has worked successfully in places like Beaufort West, Western Cape, because the initiative has been championed by individual municipal engineers with vision. While that’s commendable, the emphasis going forward must be that all municipalities, where applicable, make reuse a standard policy with plans in place for progressive implementation. This view is also supported

by South Africa’s National Water Resource Strategy,” Du Plessis expands.

South Africa remains overdependent on surface water. Groundwater also needs to be managed carefully as this too is a finite resource. Here, the recharge of groundwater using reuse and reclamation as a possible approach can be utilised with success to augment sur face water resources.

“The guides are there to be user-friendly and to empower municipal engineers to make the right choices. You cannot wait until you run out of water. You need to plan strategically to sustain socio-economic development within the context of climate change variability,” Du Plessis concludes.

THE SCHOOL OF CONCRETE TECHNOLOGY Contact the SCT to discuss the best concrete technology educational path for you +27 (0)11 315 0300 | sct@cemcon-sa.org.za | www.cemcon-sa.org.za

The Stellenbosch WWTW utilises MBR technology to augment its capacity

Making an impact through The availability and quality of South Africa’s bulk water resources are under increasing pressure, presenting a need for innovative responses. IMIESA speaks to Geoff du Toit (GdT), Technical Director and Associate Design Director at Zutari, about the firm’s role in engineering solutions that impact on the water infrastructure sector.

How do you view the current status of water and wastewater infrastructure?

GdT As an infrastructure engineering and advisory practice, we are acutely aware of the challenges of ageing water and wastewater infrastructure. This scenario is compounded by limited investment to upgrade and refurbish infrastructure at a municipal level for the past few decades. This is due to the loss of

36 IMIESA March 2023

WATER TREATMENT INFRASTRUCTURE reliable water supplies are crucial for waterscarce countries like South Africa. In this respect, the infrastructure we design and build now – such as dams, pipelines and treatment works – must factor in the realities of a changing climate. We also try to tailor our designs to operators to ensure designs are intuitive and technologically appropriate. With increased rain events, like those experienced in KwaZulu-Natal in April 2022, our designs need to anticipate such events and still achieve acceptable operational targets.

Across the board, we are currently working on a range of interesting projects in Africa and South Africa, with the Western Cape being a particularly active market. In Africa, we are conducting large Geoff du Toit, Technical Director and water resource Associate Design Director, Zutari studies in Kenya

engineering capacity within municipalities to implement necessary upgrades and refurbishment work, and a culture of nonpayment for water services, which has left many municipalities with limited budgets.

As a result, many municipalities are noncompliant regarding potable and effluent quality standards.

There have been positive gains in providing water and sanitation since 1994 that have significantly improved living standards. However, more needs to be done. The decision by the Department of Water and Sanitation (DWS) to reintroduce its Green and Blue Drop audit process is a vital mechanism to ensure municipalities are held accountable.

What is Zutari’s contribution to effecting meaningful change?

Managing water demand and securing

LEADING WATER PROJECTS and Uganda as part of their national water planning studies. We are also involved in treatment projects in Namibia, Botswana, Lesotho, Mozambique and Ghana.

The upgrade of Cape Town’s Zandvliet WWTW to 90 Mℓ/day has enabled significant development in the area to continue and meet the growing demand for accommodation and services

What are some of the key trends in water and wastewater utilisation?

There is a lot of interest in the water-energyfood nexus and how we need to start thinking about our resources differently. Wastewater treatment facilities should be rebranded as resource recovery facilities, as they are sources of water, nutrients and energy if harnessed intelligently.

Alternative water sources in the potable water space include seawater desalination in coastal areas, groundwater management and treatment, as well as water reuse. All three will form a key component of South Africa’s current and future water mix, and have received a lot of interest from a number of clients investigating the potential in their respective jurisdictions.

The big challenge for desalination is that it’s very energy intensive. There is a lot of research underway to find smart ways of generating the necessary energy on-site while also making the process as efficient as possible. Energy recovery mechanisms and advancements in membrane manufacturing, among other innovations, are all incrementally bringing down this major cost component.

On the water reuse side, Southern Africa is widely regarded as a pioneer in wastewater reuse due to the Goreangab Water Reclamation Plant outside Windhoek, Namibia. Much of the research and development work that informed the plant design was undertaken at the CSIR in Pretoria over an extended period before being implemented at full scale in Windhoek in 1968. It has a capacity of 21 Mℓ/day and provides a significant portion of the water supply to Windhoek.

Remarkably, despite this success, there has been very limited uptake for potable reuse in South Africa, with only a handful of smallscale plants in operation, the most significant being the Beaufort West Reuse Plant. That is almost certain to change given our level of water scarcity, along with a sharp increase in urbanisation and population growth. We have realised that water reuse is very well understood from a technical perspective; however, it is the social perception, which can rapidly become politicised, that is the most likely impediment to its implementation.

What are some of the potential barriers to reuse?

Educating communities is vital so they understand the rationale and are assured that

it is safe, which it is. We use the example of the natural water cycle, taught in school, versus the urban water cycle, which we conveniently ignore. Fundamentally, water used in inland towns and cities is returned to water courses from which it is abstracted by downstream communities and used again and then returned. Thus, many South Africans are already practising water reuse without realising it. This is termed de facto water reuse. Actively reusing water simply acknowledges the source of the water and holds the treatment to a much higher standard to ensure that it is safe to drink. The challenge is to design a transparent system that can be validated on a continuous basis to ensure it is doing what it is supposed to.

Which alternative water process technologies work best?

The multibarrier approach for water reuse has been almost universally adopted. Here, the failure of any one barrier is addressed by another. In terms of technology, there are two primary treatment trains utilised for water reuse – namely membrane and carbon trains.

Membrane trains utilise reverse osmosis (RO) membranes to effectively concentrate pollutants and separate the ‘brine’ stream from the treated water. This approach is used extensively in Singapore and other parts of the world; however, it is energy intensive and merely concentrates the pollutants, which still need to be disposed of.

Carbon-based trains, in contrast, utilise oxidation and biological filtration to effectively reduce the organics and contaminants in the water to food, which is readily consumed

Zandvliet WWTW: the high effluent water quality will enable water reuse should the city of Cape Town wish to pursue this further

by biological organisms in a controlled environment. The filtered water is further exposed to adsorption via granular activated carbon, ultrafiltration and ultraviolet advanced oxidation processes (UV AOP). The biological waste product is much easier and safer

IMIESA March 2023

37

LEADING WATER PROJECTS

to dispose of, and this process yields more treated water, requires significantly less energy and is significantly more environment friendly.

Are you working on any local reuse projects?

We are currently supporting the City of Cape Town in an extensive review of water supply sources to augment its surface water supplies. This includes a number of potential water reuse studies, including the 70 Mℓ/day Faure New Water Scheme and the 50 Mℓ/day Cape Flats Aquifer Management Scheme. Characterising the source waters has been challenging and very expensive, as South African laboratories are not yet equipped to test contaminants to the levels required. However, developments in passive sampling and non-targeted testing are allowing source waters to be characterised at a far reduced cost. This is a game changer for reuse in terms of ease of ongoing water quality monitoring and analyses.

Eskom load-shedding has resulted in ‘water-shedding’. How can this

be managed to ensure sustained delivery going forward?

Very little, if any, of our infrastructure was designed for ongoing load-shedding scenarios, and even where diesel gensets have been installed, there are still major logistical challenges to ensure that critical installations like pump stations are operational 24/7. The design paradigm was always based on the assumption that power would be available.

Going forward, our designs need to accommodate the scenario where power is intermittently available. This may require on-site power generation or increasing the capacity of the infrastructure such that it can operate for shorter periods of time.

Cape Town is extremely fortunate in that much of its potable water infrastructure operates largely by gravity from dams in our mountain catchments with minimal power requirements. Johannesburg and Nelson Mandela Bay, as we have recently seen, are not so lucky.

Regardless, we must design infrastructure to be more energy efficient – through efficiency improvements in wastewater

aeration, harnessing excess hydropower using ‘pump as a turbine’ (PAT) technology, or utilising the inherent calorific energy in our wastewater sludge to drive gas turbines.

All these options are being considered by a number of our clients, and I truly believe that we will see some innovative and groundbreaking projects come to light in the near future to address our new, energyconstrained paradigm.

And in closing?

We have had decades of underinvestment in water treatment infrastructure and are experiencing the consequences of constrained economic growth and reducing water quality. But we are now at an exciting turning point, with some significant opportunities and challenges. There is a lot to lose if we do not act soon, but even more to gain through good stewardship of the infrastructure we have, careful consideration of alternative water sources along with renewed infrastructure investment, and partnering with citizens, public and private institutions to renew pride in our water treatment infrastructure.

The Welvanpas WTW in Wellington, Western Cape

38 IMIESA March 2023

WASTE & RECYCLING

Kendal’s new ADF design promotes water reuse The construction of a new ash disposal facility (ADF) at Eskom’s Kendal Power Station will meet operational requirements until 2032, with the multifaceted contract being undertaken by joint venture partners Concor and Lubocon Civils.

Silt trap 1 (right) and silt trap 2 (upper right) being constructed adjacent to the clean and dirty water channels around the new ADF

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uilt on a 65 hectare site, the new facility will replace Kendal’s existing ADF, which is reaching the end of its operational life. The design includes a subsoil drainage system, which allows clean groundwater to run into a clean water dam.

“The various infrastructure elements of this contract all make sure that polluted water is kept separate from clean water,

and that water can be recycled to reduce consumption,” explains Pierre van Vuuren, contracts manager, Concor.

The design of the ADF incorporates an impermeable liner placed over the subsoil drainage system, while another drainage system is installed above the liner. The upper system allows water contaminated by ash to be channelled to the pollution control dam from where it can be used for dust suppression. In

Finalising the construction of silt trap 1 adjacent to the ADF’s water channels

turn, clean water is channelled to its dedicated dam and is returned to the power station for reuse.

Constructing the new ADF has also required the diversion of an existing natural stream. This required the establishment of a new 3 km channel measuring 30 m in width and formed using a combination of gabion systems to execute an environmentally engineered solution.

Kendal Power Station’s existing ADF (left) separated by v-drains and an access road from a neighbouring farm dam (right)

IMIESA March 2023

39

WASTE & RECYCLING

Growing market for waste challenges Dolphin Coast Landfill Management (DCLM) owns one of the largest hazardous landfills in KwaZulu-Natal (KwaDukuza) and is expanding its footprint to Gauteng.

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oncerns over the environment and landfill space continue to escalate as the world’s population grows and more waste is generated. It is not always possible to stop using landfills. But companies are looking to embrace the circular economy and are searching for alternative treatment methods for high hazardous waste streams. There is a huge drive to zero waste. This makes the waste management sector an exciting and demanding space,” says Nick Mannie, MD of DCLM. Operated by Veolia since 2019, DCLM specialises in the management of both liquid and solid hazardous and non-hazardous waste.

The company was formed 10 years ago and develops industry-specific waste management plans. “We implement the most optimal waste management solution for our clients, which is tailored to identify and recover additional resources, increase recycling and avoid disposal costs,” adds Mannie.

Nick Mannie, MD of DCLM

Innovation According to Mannie, DCLM has benefited greatly from the Veolia acquisition. “Veolia is the world reference in the management of solid or liquid non-hazardous or hazardous waste.

It has a Business Support and Performance Department where, for instance, if DCLM is searching for a solution for a particular waste stream, the department will consult a global technical team of resource specialists who can find the best suited solutions and practices. The Veolia brand and reputation in the market put us on a good footing to have high-level discussions and engagements with different industries.”

DCLM has prioritised innovation and has a technical team that evaluates waste streams, and looks to reuse or repurpose them. The team also tries to create a market for these repurposed waste streams. “We have key people in our team that engage with our clients on a daily basis regarding challenges and

solutions as concerns waste generation. Very often, effluent can be treated to a standard where it can be reused in a factory’s own internal processes rather than using additional raw water,” explains Mannie.

Three treatment technologies for liquids are used on-site: • reverse osmosis plant • vibration shear enhanced process that is a membrane separation technology platform for tough effluent streams • EVALED process plant (designed and developed by Veolia).

“The opportunities are endless, but DCLM has chosen focus areas, in which it has finetuned its expertise. Currently, we mostly work within the pulp and paper, oil and gas, mining, minerals (fertilisers), food and beverage, and manufacturing markets.”

There is also an on-site laboratory where hazardous waste goes through an initial testing process to determine the best treatment method. DCLM is able to provide high-quality

DCLM owns one of the largest hazardous landfills in KwaZuluNatal (KwaDukuza)

40 IMIESA March 2023

DCLM is able to provide highquality environmental testing and monitoring, and recently invested in new technology for the testing and screening of hazardous waste streams

environmental testing and monitoring, and recently invested in new technology for the testing and screening of hazardous waste streams. The laboratory is the confirmation and verification point where a decision is made to either accept or reject a waste stream.

Safety, legal compliance and certifications The KwaDukuza landfill site is classified as a Class A Landfill [(H:H) (Highly Hazardous)] with the capability of accepting all types of waste.

It has the following certifications and professional affiliations: • Laboratory Quality System: ISO 17025 • Environmental Management System: ISO 14001 • Health and Safety Management System: ISO 45001 • IWMSA Member (Institute of Waste Management of Southern Africa) • CAIA Member (Chemical & Allied Industries Association) • Level 1 BBBEE accreditation.

As an accredited service provider, DCLM has a responsibility to ensure the correct handling, classification, analysis, transportation and disposal of hazardous waste. The company further recognises that waste management can have an impact on the health and safety of its employees, and therefore identifies such risks to minimise, reduce and eliminate harm to employees and any other persons associated with its business activities.

“Safety is one of the key focus areas in our business and a huge priority for our holding company, Veolia. We are fortunate to have global exposure and often adopt safety measures from the Group. Contractors and staff are trained on using the correct personal protective equipment as well as the handling and preparation of different waste streams. Employees at the coalface of the operations are constantly trained and educated on safe work procedures, planned task observations, treatment methodologies, and establishing the nature of the waste streams. Safety officers on-site play an active role in embedding a safety-oriented culture and implement corrective measures should anyone fall short of our high safety standards,” adds Mannie.

After a successful decade of waste management in KwaZulu-Natal, DCLM will be expanding its footprint in the coming months to Gauteng, with technical personnel and a fleet. “DCLM is playing a pivotal role in assisting companies to achieve their ESG (environmental, social, governance) goals and attain the UN Sustainable Development Goals,” concludes Mannie.

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WASTE & RECYCLING

So, your municipality needs a new landfill?

Delving into development and design Uncontrolled dumping is a major environmental threat and needs to be urgently eradicated within South Africa’s towns and cities

Part 1 of 2

The entire process, from determining the necessity for a landfill to commissioning it, is a multifaceted one that requires careful consideration and expert knowledge. In the following commentary, Envitech Solutions’ Kris Matulovich (KM), associate director, and Molly McLennan (MM), senior design engineer, provide responses to common questions concerning the development of a municipal general waste landfill.

Considering the philosophy of ‘zero waste to landfill’, do we still need landfills?

KM Despite initiatives to reduce waste and the idea of achieving ‘zero waste to landfill’, the reality of litter, illegal dumping and overflowing landfills means that landfills are still necessary for now. The cost of alternatives like incineration, biodigestors and large-scale composting can also Kris Matulovich, be prohibitive. While government associate director, Envitech Solutions policies are encouraging progress, new landfills are required to operate a materials recovery facility (MRF) alongside the landfill. Ultimately, achieving zero waste to landfill requires a combination of community responsibility, costeffective alternatives and improved waste management practices.

Can waste management be outsourced?

KM Waste management is a crucial public service that must be managed effectively and efficiently to protect the health Molly McLennan, and well-being of the community senior design engineer, and the environment. While Envitech Solutions private sector waste management

42 IMIESA March 2023

facilities exist, municipalities are ultimately responsible for the collection and disposal of household and business waste.

While contractors may be appointed to oversee landfill operations, outsourcing waste management entirely to the private sector may lead to conflicts of interest and loss of control over the cost of the service. Therefore, it is generally not advisable to rely solely on private sector waste management for an essential public service.

How and when does a municipality establish a need for a landfill?

MM Establishing the need for a landfill is a complex process that involves careful consideration of various factors. The most common reason for the development of a new landfill is when the existing landfill is almost full or overflowing. However, other factors such as expanding towns and villages, rising transportation costs to distant landfills, and government policy requiring the consideration of alternatives can also prompt the need for a new landfill.

District and local municipalities work together to plan waste management services at a regional and even provincial level. To determine

the need for a new landfill, environmental factors such as the physical landscape, population densities and growth points, as well as feasible transport routes need to be taken into account.

A formal ‘gaps and needs analysis’ study is often carried out at a regional level to determine the gaps in service delivery for existing and planned communities. This study informs budget allocations and planning for the future.

The development of more transfer stations and fewer centralised landfills is a growing trend in waste management services planning.

How are suitable sites chosen for a landfill?

MM Choosing a suitable site for a landfill involves a thorough feasibility study of possible locations based on various factors, including the capital and operating costs of the landfill and related waste transport costs. The two or three most promising sites are then subjected to in-depth environmental impact studies, which include a public participation process.

Based on the results of the studies and public input, the municipality selects a preferred site.

This information, along with an engineered design for the facility, is then presented to the relevant government bodies for approval.

The site selection process is a crucial step in ensuring that the landfill operates efficiently and with minimal environmental impact.

Which government department grants a landfill licence?

KM Local municipality landfill sites for general waste are granted a licence by the relevant provincial environmental department. For example, a site in Mpumalanga would be granted authorisation by the Mpumalanga Department of Agriculture, Rural Development, Land and Environmental Affairs. However, larger regional landfill sites, as well as hazardous landfill sites, require authorisation Barriers are necessary to protect the ground and groundwater from contamination

by the National Department of Forestry, Fisheries and the Environment (DFFE).

In all cases, the application must also be reviewed by the Department of Water and Sanitation, who will give a record of decision (ROD) to the relevant environmental department, which will inform the licence and conditions therein.

What is the design engineer’s role and design approach?

MM The overall project objective is for the engineer to use their engineering skill, experience and judgement to provide an environmentally acceptable landfill facility to accommodate the disposal of general solid waste. This includes the following: • to classify the waste disposal facility in terms of waste types, size of waste stream and the potential for leachate generation • to confirm the suitability of the proposed landfill site and surrounds for the development of the long-term waste disposal facility • to develop a preliminary design that meets the disposal need and that mitigates any identified environmental impacts and critical factors – this includes knowledge on the use of geosynthetic materials • to confirm the service life of the landfill, in terms of both capacity and the service life of individual materials and systems that make up the facilities.

The engineer produces a design report to document the design criteria, assumptions and preliminary details of the proposed waste disposal facility for the purpose of incorporation into the new waste management licence application to be submitted to the regulatory authorities.

The design report includes the preliminary design drawings and a construction quality assurance (CQA) plan, which outlines quality assurance protocols during construction. This documentation must satisfy the requirements of the DFFE’s checklist that must now accompany all design reports.

How is a landfill site classified and what does the classification mean?

KM Waste is classified according to the National Norms and Standards as published in Government Gazette Notice 634, 635 and 636 of 2013. A typical municipal general waste

WASTE & RECYCLING

Landfill airspace refers to the vertical space above a landfill where waste can be deposited, typically limited by regulatory permits or physical capacity.”

Choosing a suitable site for a landfill involves a thorough feasibility study of possible locations based on various factors, including the capital and operating costs of the landfill and related waste transport costs

site is called a Class B site and the waste type is classified as a Type 2 waste. The main purpose of the classification is to prescribe the type of barrier system required under the waste landfill, as a minimum. Barriers are necessary to protect the ground and groundwater from contamination.

The barrier, also called the lining system, is the most expensive element in a landfill development. Natural clay layers may form part of the barrier if suitable clay is available.

Generally, though, the barrier is made up of various geosynthetic layers that often include a geosynthetic clay liner, which is used when natural clay is not available.

How do you size the landfill?

MM The expected volume of waste coming to the landfill is based on the population or number of households contributing.

Historically, we know that in a typical town, there are five people per household contributing about 2.2 kg of waste per household per day. Presuming all this waste gets to the landfill, as well as waste from the business district, one can calculate the volume of waste expected to be landfilled. The waste will be covered on the landfill at a ratio of about 1:5 (cover material to waste). The cover material volume required is factored in.

Taking into account that the waste will be compacted, one can calculate the volume of waste in the landfill for any given time period.

To be cost-effective, a landfill should have a capacity of at least about 15 years.

For ease of estimation, it is accepted that one

44 IMIESA March 2023

tonne of compacted waste will take up one cubic metre of airspace. Depending on what recycling initiatives are in place, a percentage of the waste may not be landfilled, which is also taken into account.

So now the sizing becomes an exercise in geometry. A given volume divided by the height limit yields an area required. The engineer would then optimise the footprint area shape based on the actual site topography and shape.

The goal when sizing a landfill is to maximise the life of the site by making the best use of the available footprint. The biggest cost component is the basal liner system, so it makes sense to maximise the height. Height is influenced by requirements in the environmental impact assessment,

The goal when sizing a landfill is to maximise the life of the site by making the best use of the available footprint

but also by the availability of cover material for operations and the overall stability of the landfill body. An optimal design would balance the volume of excavation below ground with the volume of cover soil required over the life of the site.

Finally, the engineer must ensure that the area on top of the landfill is still large enough in the final years to accommodate the working space required for the operations, taking into account the sloping sides of the waste body.

Calculations are carried out by the engineer to check the stability of the landfill, and adjustments may be made to the geometry to ensure the required factor of safety is achieved.

What calculations does the regulator need to see?

KM While the regulator will need to be satisfied that the landfill is cost-effective and not a wasteful design from a cost point of view, they would be primarily concerned with confirming that stability assessments have been carried out, geotechnical and geohydrological studies have been undertaken, and that site geometry and drainage have been considered by a competent professional.

Stability calculations include the global stability of the planned waste body, as well as the veneer stability of the side slopes. Theoretical calculations would be supported by laboratory testing on the actual materials to be used in the lining system. Other calculations to be submitted are estimated leachate seepage volumes through the proposed liner.

For more information on what government legislation and guidelines are relevant to the development of a landfill facility, visit our site at www.envitech.co.za and look out for Part 2 of this question and answer series in an upcoming edition of IMIESA.

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WASTE & RECYCLING EnviroServ Waste Management staff standing in the new landfill cell extension. From left: David Malan, senior landfill supervisor; Herbert Gxavu, landfill supervisor; Sue Alcock, operations manager; Bongile Faca, plant operator; and Vusumzi Skawuti, maintenance assistant

Aloes Cell 3B extension incorporates piggyback lining The addition of a new landfill cell at EnviroSer v’s Aloes Waste Management Facility in Gqeberha is designed to keep pace with the disposal requirements of a mix of general, industrial and hazardous waste customers, including the motor industr y and tanneries.

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onstruction of Aloes Cell 3B, by Stefanutti Stocks, started in November 2021 and was completed with approximately 200 000 m3 of airspace capacity in September 2022.

The cell design took six months to complete from a conceptual to a detailed design level. This involved a team of five engineers working together with two draughtsmen, and with input from an environmental geochemist and environmental scientists that have been conducting the groundwater monitoring on-site.

Jabulile Msiza, head: Waste Department, Jones & Wagener, was responsible for the project. The overall team also included an independent third-party consulting engineer to conduct peer review of the quality assurance process, and an engineer seconded full-time to the site from the Department of Water and Sanitation to gain construction super vision experience towards their professional registration requirements.

Cell 3B was designed as an extension of Cell 3A. The lining system of future Cell

46 IMIESA March 2023

3C will tie into that of Cell 3A and 3B to form the final Aloes Cell 3. “The new Cell 3B has its own leachate collection, leakage detection, contaminated stormwater and clean stormwater drainage systems, but these tie into the existing management infrastructure,” says Msiza.

Landfill gas management The new Cell 3B is positioned on the old waste site of the previous Cell 1, and a gas drainage layer has been provided to vent any landfill gas that may have accumulated.

“The gas layer and extraction pipe system act as a subsur face drainage system in which any water or leachate from Cell 1 may be collected and gravity drained towards the southern perimeter of the site. Since the waste in Cell 1 is old, large quantities of landfill gas are not anticipated and a passive venting system manages the landfill gas produced,” Msiza continues.

The gas extraction and subsur face drainage system consist of a 200 mm thick selected granular layer, with two 110 mm diameter per forated HDPE pipes directly above the geogrid reinforcement within the granular gas layer. The pipes pass under

the edge control berm and discharge into HDPE manholes. Whirlybirds, connected to the top of the manholes, manage passive extraction of the gas.

Leakage detection A leak detection system was included in the design above the secondar y composite barrier system (compacted clay layer works from the site in intimate contact with a 1.5 mm double-textured HDPE geomembrane liner), consisting of a 150 mm thick, 19 mm stone layer draining into a network of 160 mm diameter HDPE pipes. The pipes were sized to consider chemical and biological clogging factors and a factor of safety exceeding 5 was obtained for the leakage detection pipe drainage system.

The system exits the cell through a liner penetration through the edge control berm and discharges under gravity via a 200 mm diameter pipe into a monitoring/collection manhole. The leachate is then pumped to the leachate pond.

Leachate collection Based on the mean annual precipitation of

WASTE & RECYCLING

along the inner crest of the edge control berms (embankments) and any stormwater flowing down the slopes of the waste body is directed into these drains and a silt trap,” Msiza explains.

The contaminated stormwater collected in these drainage canals is directed to low points along the cell crest, where the stormwater discharges into an Armor flexlined trapezoidal canal.

Unique aspects 490 mm for the site, the leachate collection pipes were spaced conser vatively at 60 m centres. This yielded a maximum head of 120 mm within the 300 mm thick leachate collection layer.

“Although significantly less flow is anticipated in the leakage detection drainage layer, we specified the same pipe spacing to ensure prompt drainage to the nearest outlet,” says Msiza.

Stormwater management The three embankments of Cell 3B act as edge control berms against

which waste is filled as the waste body rises. Stormwater that falls directly onto the waste body is deemed to be contaminated and is collected in a stormwater drain and directed into a lined storage/containment facility.

Part of the project included relining of the stormwater dam into which these berm drains discharge. The liner was fully protected with a polymer-reinforced concrete layer that acts as a ballast layer.

This will in future enable the desiltation of the dam without liner damage.

“Lined open drains have been constructed

“The unique part about the Aloes construction is that it was built over an old landfill, which was capped in 2008 with a thick soil layer. We had to do piggyback lining, in the form of a basal reinforcement layer – a geogrid – to add strength and remove the stress of any settlement that might happen, so it does not transfer into our new liner system, which could then crack and breach,” adds Msiza.

Relevant approvals were granted by the Department of Forestr y, Fisheries and Environment once construction was complete, and the cell began accepting waste in the last quarter of 2022.

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RENEWABLE ENERGY & ELECTRIFICATION

Solar tax rebates a step in the right direction

Providing tax incentives for households to invest in rooftop solar is a commendable step by government to alleviate the energy crisis. However, Dr Andrew Dickson, engineering executive at CBI-electric: low voltage, believes that a number of scenarios should be considered to work effectively.

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s announced by South Africa’s Minister of Finance, Enoch Godongwana, during the 2023 National Budget Speech, individuals who install rooftop solar panels from 1 March 2023 will be able to claim a rebate of 25% of the cost of the panels for the 2023/24 tax period, up to a maximum of R15 000.

“As making a meaningful dent in the energy crisis requires mass adoption at a rapid pace, this incentive might not result in sufficient adoption of solar in the residential sector, which constitutes a significant portion of the building types in the country,” Dickson explains.

He says three options should be considered. First, the extension of the rebate should include a greater part of the system – batteries and inverters. As he points out, to be able to use panels in the first place, an inverter is needed, and storage is crucial if the energy absorbed by the panels during the day is to be available at night.

Second, Dickson says a higher rebate percentage for the solar panels should be considered. “A rebate of 25% is equivalent to about a 5% discount available in many

48 IMIESA March 2023

retail environments. Most people won’t install R60 000 worth of panels, as this equates to about 25 panels, which is extreme for the majority of households, thereby reducing the effectiveness of the proposed incentive. In real hard cash terms, the rebate would be about 4.5% for the lowest-income tax bracket and about 11.3% for the top,” he explains.

Lastly, he says that if the incentive is made available for longer than a year, this could also increase the uptake of these systems and go a long way towards alleviating strain on the national grid. It would also help keep small and medium-sized businesses operational, enabling the economy to grow.

“Consideration should have also been given to recent installs, as this would have derived positive sentiment from the man in the street around the action plans being put in

Dr Andrew Dickson, engineering executive at CBI-electric: low voltage

place by the government to right the energy crisis,” Dickson continues.

Cape Town example Another suggestion he makes is that National Treasury could follow the City of Cape Town’s lead by funding businesses and households for excess power generated that is fed back into the national grid.

For this financial year, the National Energy Regulator of South Africa has approved a rate of 78.98 c/kWh and an additional 25 c/kWh incentive tariff for the city to pay power sellers. Through this initiative, National Treasury has also granted the City of Cape Town an exemption from competitive bidding or tendering processes for the buying of electricity from small-scale private producers.

“This could be extended to the rest of the country to hasten the end of load-shedding.

At the same time, it could open an opportunity for the development of an entirely new business sector to facilitate the procurement of excess power from these producers,” he asserts.

“We need to focus on getting the basics right and empowering South Africans to play a part in conquering the energy crisis. It is only by doing so that we can lay the foundations for a brighter future for our country,” Dickson concludes.

RENEWABLE ENERGY & ELECTRIFICATION

Cape Town’s cash-for-power programme From June 2023, businesses and, soon thereafter, residents with City-approved generation capacity will be paid the NERSA-approved 78.98 c/kWh tariff to feed their excess energy back into Cape Town’s grid, plus an added incentive of 25 c/kWh.

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uring the build-up to this, Geordin Hill-Lewis, executive mayor, City of Cape Town, had previously unveiled the City’s Power Heroes programme, where residents are offered an incentive for voluntary energy savings at peak times.

For specialist service providers, these developments provide a major boost for the self-generation renewable energy market in South Africa, says Ross MainsSheard, director at Versofy Solar. He points to successful examples like Vietnam – an emerging economy with aspirations to become a developed, high-income nation by 2050.

In April 2020, Vietnam announced a 31 December deadline for those wishing to enjoy a 20-year rooftop solar feed-in tariff of US$0.0838/kWh. According to PV-Tech,

South Africa

Vietnam’s rooftop solar installations skyrocketed after the announcement (particularly in the last two months of 2020) by 2 435%, “rising from a 2019 base of 378 MWp to 9.583 GWp, spread across almost 102 000 systems.”

On 31 December 2020, the Vietnam Ministry of Industry and Trade announced that cumulative PV capacity had reached 16.449 GWp (13.160 GWac). This included ground-mount and floating solar projects.

Significantly, Vietnam uses gross metering for rooftop solar PV producers instead of net metering.

Metering and storage “We urge government and local municipalities to make the installation of bidirectional meters a feasible one,” Mains-Sheard notes.

“The current costs of these meters may be a barrier to entry, as the payback period on the meter itself is not attractive.”

Storage of renewable energy holds the key, he adds. “At a micro view, rooftop solar with storage has proved that renewables have the ability to provide perpetual energy generation.

When aggregated, it has the ability to make a meaningful difference to both the adoption of renewables but, more importantly, dependence on the national grid.”

In the past year, Versofy has supplied: • over 9 000 solar panels, which are producing more than 18 MWh/day (4.14 MW installed) • more than 1 700 batteries, equating to approximately 9 MWh of energy storage • 1 000 inverters.

Put in perspective, 18 MWh/day can power a 300-bed hospital or 1 000 households.

RENEWABLE ENERGY & ELECTRIFICATION

The grid and its digital twin

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As a diagnostics tool, digital twinning (a virtual representation of a physical asset or system) can provide valuable insights into why a power outage occurred, determine the root cause and build a plan that will mitigate similar, future events.

By Dwibin Thomas

ere, the power management platform – represented by the digital twin – is built on top of a model of the actual electrical network itself. This in turn introduces new workflows that find the root cause faster.

For example, it allows the engineer to replay an incident step by step, inspecting measurements on any part of the network at any time. Those same measurements from the real system can also be fed as inputs into the digital twin assets to determine if, for example, a breaker operated, and if not, why not.

Predictive maintenance is one of the most common uses of digital twinning today. For example, a digital twin of a generator can tell you when maintenance is needed by comparing the predicted to the actual behaviour based on historic activity.

Digital twins also allow operators to run simulations, which can prove invaluable for maintenance planning. A case in point is a scenario where a technician is scheduled to visit a substation to maintain transformers.

During this process, they might have to go through a complex set of operations such

as isolating each transformer from the utility and powering the downstream feeder from another transformer.

However, with digital twinning, this process can be fully simulated beforehand in the office. Then, once on-site, with a connection to the digital twin, the technician can verify the planned switching actions before executing them.

Design and energy usage Designing new electrical networks for large facilities is another important application where digital twins add value. Automation and control schemes, communication architectures, switchgear and cabling layouts benefit from being tested and validated in a digital twin simulation before investing in costly construction and commissioning.

Facility energy use forecasting and validation is another common prediction application.

Here, the digital twin of the facility is fed with the process, occupancy, temperature or other parameters. The facility digital twin outputs

the expected energy consumption over the next day, week or season. This data can justify investments, confirm the facility is operating as expected, or validate investments made in the past.

Sustainability Interestingly, one of the emerging uses of digital twin technology is in the design of environmentally conscious grid infrastructure.

The digital twin model has an important role to play in equipment and systems’ decarbonisation, as it provides valuable data at all stages of the product and project life cycle. That’s part of the future of green energy networks.

Zutari is an infrastructure engineering and advisory practice. We provide full lifecycle infrastructure solutions, across the water, energy, resources, transport, and built environment markets.

Software designed to facilitate wheeling

G

eorge Municipality is believed to be the first electricity provider in South Africa to pilot Access Energy – a freely licensed software solution that automates the reading, processing and billing of electricity smart meter data.

“The need for this became evident when we considered the scaling of wheeling and renewable energy on the municipality’s electricity grid,” says Bongani Mandla, director: Electrotechnical Ser vices, George Municipality.

“The manual billing process was one of the main challenges and resolving this meant reducing reliance and pressure on key human resources, reducing potential errors that could occur in the billing process,” he adds.

Generators and off-takers George Municipality’s current wheeling setup comprises one generator and four off-takers through Enpower Trading (a NERSA-licensed energy trader). However, the municipality is working on further improvements to its wheeling projects, including incentives for the private sector (both generators and off-takers) to participate in the programme.

Developed by Cape Town-based company Open Access Energy, the Access Energy solution allows for clients to view their consumption and billing data in real time. The sharing of this meter data is made possible through its implementation of the Eskom-sanctioned NRS049 5-2 protocol.

Open Access Energy’s second interrelated product is called EnergyPro, which is aimed at independent power producers and energy traders entering the wheeling market.

­

CONCRETE RETAINING BLOCK SYSTEMS

The Terraforce Book of Ideas A South African manufacturer with a passion for excellence and knowledge sharing, Terraforce has become a hallmark brand in the highly competitive precast concrete hollow core retaining block field.

P

roprietary by design, Terraforce blocks are engineered to perform, backed by close to four decades of dedicated research and development, which started with the S block in 1984.

Today, one of the mainstays in the series is the L range, available either with a smooth or textured surface (Standard or Rock Face option) and in flat or rounded shapes. These can be employed in combination to create landscaped terraces, mass gravity or composite retaining walls for embankments and erosion control, as well as for stormwater management, among many other applications.

“Given their complexity, the design and construction of many of these structures must be undertaken by a professionally registered engineer; so, to facilitate the

Culvert and small bridge detail A

52 IMIESA March 2023

process and add value, we developed our Maxiwall Pro design software, which is freely available to the market,” explains Holger Rust, head and founder of Terraforce.

Over the years, Terraforce has also established a library of technical manuals for use by the industry, which can be downloaded from their website. One of the most recent and best known is the updated Terraforce Design Guide for segmental retaining walls, which is based on the company’s original 1992 version. The latest edition, released in 2022, was developed with the participation of professionals in three countries in accordance with BS 8006 and SANS 207:2011.

Illustrations that inspire “However, what we really want to bring across are the endless possibilities to environmentally engineer beautiful structures,” Holger continues.

This was the motivation for the manufacturer’s latest initiative – the Terraforce Book of Ideas – which showcases creative ways to install aesthetically appealing structures ranging from beach erosion works to culverts and bridges, staircases, pedestrian ramps, sports ground seating and amphitheatres.

“The key ingredient is that the Book of Ideas is highly visual and will appeal to technical and non-technical readers alike looking for inspiration,” Holger explains.

The insights shared feature South African, as well as international projects from diverse countries that include Australia,

Canada, Egypt, Eswatini, Ghana, India, Lesotho, Morocco, Namibia, Nigeria, Spain, the UAE and UK.

Eight fascinating chapters The Book of Ideas has eight chapters, namely: • Chapter 1: Patterns and plantability – This provides an introduction to how Terraforce’s various systems can be formed. Examples include the use of round and flat face block combinations, plant box variations in sloping and horizontal patterns, plus drip irrigation lines to sustain vegetation. One of the case studies highlighted is the Jalila Children’s Hospital in Dubai – designed

by South African firm Knutton Consulting – where an innovative noise barrier retaining wall was constructed, with plantable lines incorporated. A distinctive feature is the reversal of the blocks at intervals to achieve an optimal sound reduction effect.

• Chapter 2: Features and inclinations – This chapter looks more in-depth at design options, starting with foundation detailing and wall angles. More advanced designs demonstrate the possibilities in terms of varying inclinations and curves.

• Chapter 3: Corners – Whether to match the terrain or create a design element, corners are an integral part of most structures. This chapter looks at corner detail options, including multiple sharp corners, round V-shaped corners and corners without cutting blocks.

CONCRETE RETAINING BLOCK SYSTEMS

Steps with L Range Blocks

the book. These are available on request as AutoCAD DWG files.

Innovation and quality

• Chapter 4: Steps and stairs – This chapter opens with a practical guide on how to employ the interlocking Terraforce 4x4 Step Block system, with reference to case studies. The balance of the chapter explores design alternatives for retaining walls incorporating staircases employing the Terraforce L range system, at times in combination with the Terraforce 4x4 Step Block to form straightforward and intricate systems.

• Chapter 5: Seating – Steps and seating often go together; in this chapter, there are outstanding examples of arenas and amphitheatres designed and built for schools, communities and businesses.

The 4x4 Step Block comes into its own here, with a detailed breakdown provided on installation techniques, as well as technical drawings of local and international projects.

• Chapter 6: Contractor’s check list – Before any design gets to the build stage, however, a comprehensive series of processes and procedures must be followed to ensure safe retaining wall structures. That’s the core focus of this chapter, which drills down into crucial categories, namely: Retaining Wall Design, including when a design needs to be reviewed and signed off by a registered professional deemed competent in geotechnical engineering; Construction, itemising the essential sequence required to obtain a completion certificated; and Monitoring, Maintenance and Restrictions.

In terms of the latter, once a structure is completed according to its design, any future alternation considered needs the engineer’s approval, where applicable.

Routine structural inspection of reinforced soil structures is equally important, and records must be kept.

• Chapter 7: Typical cross sections – This chapter contains examples of typical cross sections for retaining applications and underscores the level of engineering detail required as designs become more complex.

• Chapter 8: DWG file index: Last but not least is a listing of almost all of the technical drawings contained throughout

“We’ve always prided ourselves on innovation, and the Terraforce Book of Ideas illustrates this with real-world examples that optimise form and function to perfection,” adds Rust.

“Working with our licensees and the broader consulting engineering and specialist contracting community, we continue to push the boundaries of possibilities,” Rust concludes.

L Range Step Block

BOOK OF IDEAS To download the latest version of the Terraforce Book of Ideas, visit http://designguide.terraforce.com/download-pdf

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ROADS & BRIDGES

Research team develops practice manual for paved low volume roads projects Nearly 600 000 km, or 80%, of South Africa’s road network is unpaved. Although predominantly defined as low volume, these routes have major socio-economic importance for rural communities and should not take a backseat in terms of budgeting and maintenance, says Professor Philip PaigeGreen from Paige-Green Consulting. By Alastair Currie

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ccording to the SAICE 2022 Infrastructure Report Card for South Africa (2022 IRC), the overall current state of South Africa’s paved and unpaved network – with some exceptions like the Sanral network – is unknown, based on up-to-date visual condition index (VCI) assessment data.

Research also found that few provincial and municipal roads authorities maintain a pavement management system. That leads to inadequate funding allocations, as well as reactive maintenance, which is further compounded by a lack of in-house engineering capacity.

This resulted in the 2022 IRC allocating an E (defined as “unfit for purpose”) for provincial and municipal unpaved roads. In turn, “paved provincial roads” and “paved roads in the major urban areas” scored a D (defined as “at risk of failure”), and “other municipalities’ paved roads” a D-.

54 IMIESA March 2023

In terms of South Africa’s gravel road footprint, the 2022 IRC stated that it “is too extensive and the budgets too constrained for the entire network to be kept in a satisfactory condition.”

Another key observation was that “areas where greater policy clarity is desirable include: (a) a consistent methodology for prioritising road expenditure, and (b) a consistent methodology to estimate the significance of roads within provincial networks.”

Unpaved roads are not substandard alternatives “In this respect, gravel roads represent a sizeable percentage of most networks in leading countries and, when well designed and maintained, deliver sterling service,” says Paige-Green. “So, there’s no reason to always regard them as substandard alternatives to paved routes.”

Over the years, Paige-Green has gained in-depth knowledge that spans some 37 years with the CSIR, and subsequently as the founder of his own consulting firm.

“Back in 1976 when I joined the CSIR, extensive research and development (R&D) was already taking place on what was then referred to as ‘lightly trafficked roads’,” PaigeGreen explains. “This became a key interest for me and, around 1981, I became extensively involved in research work on gravel roads, which was also the topic for my doctoral studies in engineering geology.”

TRH 20 “In my view, the industry hasn’t progressed very far since the 1980s. The Technical Recommendations for Highways (TRH) 20 specification covering the structural design, construction and maintenance of unpaved roads has been available since the initial draft in the early 1990s. An update was released in 2009. However, TRH 20 still hasn’t been extensively adopted by some of the roads authorities,” he explains.

Paige-Green says some may view TRH 20 as over-design and, therefore, too costly. “However, studies have shown that investing in the right materials and construction methodology up front does pass on significant, longer-term savings. Examples include less maintenance and a reduction in gravel losses, benefiting the roads authority, as well as improved road riding quality, which benefits the road user.”

PICC initiative and LVR Design Manual From 2014, the Department of Transport has made it a requirement for provincial roads authorities to have an active and current pavement management system. Each province is required to conduct VCI assessments annually on their paved network, and every two years for unpaved roads. Monitoring traffic volumes has a direct bearing on life-cycle costing. It also provides an indication on highertrafficked gravel routes that it might be time for an upgrade.

To push forward the mandate for unpaved roads, Sanral initiated a joint study, which comprises six industry experts. This team, which includes Paige-Green as a materials specialist, was put together by Professors Wynand Steyn and Gerrit Jordaan at the University of Pretoria on behalf of Sanral (as part of the agency’s research programme).

The primary objective was to produce a Low Volume Road (LVR) Guideline Manual that will subsequently become a TRH 24 specification.

The impact of economic issues is critical, and Professor Don Ross and Dr Matthew Townsend from the University of Cape Town are providing essential economic input into the project. The project is being guided by Sanral’s Gerhard Fourie in Cape Town.

ROADS & BRIDGES

The manual was submitted in October 2022 and will now be applied as a design recommendation on seven rural gravel access roads identified for upgrading by Sanral in three provinces (Eastern Cape, KwaZulu-Natal and Limpopo). A number of these routes, which vary in length from 7 km to around 30 km, are in agricultural areas that provide transit for machinery, plus access to produce markets.

DCP design approach One of the key recommendations in the manual is the employment of the dynamic cone penetrometer (DCP) method, which is also currently being adopted by the Africa Community Access Partnership (AfCAP) on LVRs. Where DCP testing confirms the unsuitability of in-situ material, the alternative recommendation is to apply the latest nano-organosilane modified emulsion (NME) technologies now available on the market. Wherever practical, labour-intensive construction techniques should also be employed.

As Paige-Green explains, a key benefit of using NMEs is that – in most cases – in-situ materials can be used to construct the road, significantly reducing the need for imported commercial gravels. To illustrate the point, the current estimated cost of upgrading a standard gravel road is around R10 million to R12 million per kilometre, compared to approximately R2 million to R4 million per kilometre with the NME approach.

“In the past, engineers have tended to intentionally reduce conventional pavement standards for LVRs. Our initiative with TRH 24 is working in the opposite direction by setting out to improve the unpaved road standard,” says Paige-Green.

Sand seals As he points out, South Africa has a successful long-term track record in sealing LVRs, a prime example being the use of sand seals in the Kruger National Park dating back from the 1960s. Essentially, the approach entails spraying the prepared sub-base with an asphalt emulsion followed by the addition of fine aggregate. When applied correctly, these surfaces can last for three years or more before needing to be resealed.

Various other appropriate seals are also recommended, with input into the TRH 24 Guideline from team member Gerrie van Zyl, an international expert on low-cost bituminous surfacings.

Traffic threshold As part of the Sanral initiative, the engineers employed on the seven upgrade projects will receive comprehensive training on the new TRH 24 Guideline Manual.

“It should be noted that NME technology is not only applicable for the upgrading of LVRs but has effectively been tested for designs up to 30 million standard axles (and more),” he continues.

The TRH 24 Guideline Manual includes recommendations for water crossings, factoring in the catchment areas, known rainfall patterns, as well as the potential for future increased precipitation due to climate change.

Sanral pilot project timeline The upgrade projects (including trial sections) are expected to run over a four-to-five-year period,

which, in the later stages, will include monitoring to determine the effective performance of the design and construction method implemented. At this stage, a number of these projects have advanced to the tender stage, with construction anticipated to start during 2023.

“With decades of applied R&D experience, South Africa is widely seen globally as a leader in LVRs. We have spearheaded the application of technologies that make LVRs more durable and cheaper to construct. We now need to implement this approach on a wider scale,” adds Paige-Green.

“That’s why these seven initial pilot LVR projects are especially exciting, as they provide an invaluable opportunity for a new generation of engineers to embrace DCP design methods, and NME techniques, in progressively upgrading the country’s gravel network,” PaigeGreen concludes.

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HEALTH & SAFET Y

Revised OHS Act

requires far stricter compliance Given the importance of occupational health and safety (OHS) in the workplace, there has been a growing need to ensure that existing procedures in South Africa are in line with global best practices.

I

n response, the Department of Employment and Labour, working in collaboration with lawmakers and business professionals, has drafted an amendment to the OHS Act (No. 85 of 1993), which is currently out for public comment.

“It has become abundantly clear that the OHS Act in its current format needs an update given how quickly the corporate environment is developing and changing. Every aspect of every operation should be designed to increase safety,” explains Viann Nel, health and safety practitioner at Afroteq Advisory.

“Getting companies to meet the bare minimum requirements is no longer good enough. I believe the revised legislation will be a major step forward by shifting current policies and procedures from a theoretical perspective to a practical, proactive approach,” he explains.

In the interim, the Department of Employment and Labour has directed all health and safety practitioners to ensure the proposed changes are put into practice by treating the Act’s developments as though they had already been implemented. Close to a thousand inspectors have been recruited to travel to enterprises randomly to assess their work environments for health and safety precautions, issuing fines where necessary.

Risk management plan Every organisation, regardless of its size, will be expected to have a risk management plan

56 IMIESA March 2023

in place, directly aligned with the hazards and Viann Nel, health and risks identified by safety practitioner, implementing suitable Afroteq Advisory and related systems, documents, checklists, and templates. also now be responsible for identifying “The new strategies will be more descriptive potential risks. in response to a thorough workplace risk Additionally, senior management must assessment, making the health and safety ensure that employees do not perform protocols easier to implement, with more any duties that lie beyond the scope of clearly defined parameters. This is in contrast the implemented risk management plan to the historically generic form of risk or beyond the scope of what has been management strategies. Policies, procedures deemed safe in the organisation. In this and updated training programmes that are respect, the risk management plan will specifically created to meet the demands of apply to both permanent and non-permanent a given workplace will need to be in place as staff members. part of specialised risk mitigation strategies,” Provision for remote workers Nel expands.

“The onset of the Covid-19 pandemic has Going forward, the amended OHS Act resulted in an exponential rise in the number of will place even greater responsibility on people who now work from home. Companies employers. However, it will also demand are therefore now also expected to make greater awareness and mandatory provision for these employees from an OHS compliance among employees as well. The perspective with regard to their health, safety latter will be expected to play an active role and the way they interact with technology in implementing and adhering to workplace (ergonomics),” Nel concludes. policies and procedures. Employees will

SPECIALIST OHS SERVICES Afroteq Advisory services include assistance in the development and implementation of workplace-specific risk assessment and risk management plans. In turn, sister company Afroteq Academy offers a range of in-person and online training programmes to assist companies and their staff to understand, develop, implement and manage OHS in the working environment.

VEHICLES & EQUIPMENT

Meeting readymix demand in Bamako Malian contractor Z For Mining (ZFM) recently acquired an ECO90 stationary concrete batching plant to support construction activity in the country’s capital, Bamako. ZFM now owns three of the four units that make up the Eurotec ECO range manufactured by leading OEM Lintec & Linnhoff.

Z

FM has been an enthusiastic advocate of Eurotec machinery ever since it acquired its first model, a second-hand ECO30, from a local contractor in 2013. The company, which provides contracting services such as roadbuilding and civil works for mines, immediately set the plant to work, producing all the concrete required for the extension of a Somisy gold mine.

Soon after this, ZFM acquired a brand-new ECO50 model that was also installed at the mine, where it supported the shotcreting of underground tunnels. Daily production output of both the ECO30 and the ECO50 varied between 10-100 m3.

Zeidan Zeidan, managing director of ZFM, with a section of the company’s ECO50 stationary concrete batch plant in the background

ZFM’s new Eurotec ECO90 installed in Bamako, Mali, will supply high-quality concrete to local contractors

The Eurotec ECO90 employs Lintec & Linnhoff’s proprietary ECS software to produce a precise and fast production rate of 90 m3

attracting ZFM’s repeat business. A further advantage is that transportation is both easy and economical. After arriving on-site, the ECO90 can be quickly installed, as it needs little to no foundation.

Nice and easy does it every time

ZFM’s most recent acquisition, a new Eurotec ECO90, began operations during January 2023, supplying readymix concrete to local contractors, many of whom will be involved in the nationwide push to increase public housing construction.

“Beginning with our very first machine, we were very impressed with how easy it was to use the Eurotec batching plants,” says Zeidan Zeidan, managing director, ZFM. “Nevertheless, with our experience and strong reputation in the construction sector, it is vital that we continue to deliver the best possible service to our clients, and this is why we add extra value by hiring expat operators to oversee production,” he explains.

“These operators have been highly trained in the art of producing concrete in the optimum way, as well as efficiently carrying out preventive maintenance to ensure our plants always remain operational and ready to serve.”

Pinpoint accuracy

After-sales backup

The ECO90 has a designed output of up to 90 m3/h with a mixer size at 2 m3 per batch, and features a cement weigher and water weigher, both of which are accurately metered using load cells. Optional additive weighers can also operate in conjunction with Eurotec’s in-house developed ECS process-control system software. The ECS program runs on a user-friendly Windows platform and helps to produce a precise and consistent blend.

During operation, the robust steel structure and thick interior abrasion-proof linings of the ECO90’s twin-shaft mixer ensure durable performance while mixing particles of up to 150 mm in diameter.

To further opimise the process, the aggregate bins are designed to enable materials to be loaded effortlessly, with minimal ramps.

This high level of functionality – with simple operation ensuring quality concrete production – is a key advantage of the affordable Eurotec ECO series. It was also instrumental in

In addition to offering user-friendly engineering design, Lintec & Linnhoff’s responsive and intelligent approach to customer support helps operations run smoothly for ZFM. Both online and in-person customer service ensures that on the rare occasion issues do arise with the plants, they are swiftly identified and resolved. Seamless parts logistics, experienced technicians and a customer-first philosophy combine to ensure productivity and profitability remain at their maximum for the customer.

“The easy contact and communication with the Lintec & Linnhoff team – and in particular the readiness of the technical team to assist in the event of any issues – was another major factor in our decision to buy additional Eurotec models,” adds Zeidan.

“Will we ever finalise our collection with the ECO120, the biggest model in the range?

Only time and infrastructure plans will tell!”

Zeidan concludes.

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VEHICLES & EQUIPMENT

Leading from the front, Isuzu Motors South Africa recently recorded a major new milestone when it celebrated its 10th consecutive year as the top local truck brand, according to the latest NAAMSA report, selling 3 304 units in 2022.

W

e have several reasons to celebrate when ringing in the new year, with such an excellent sales record, the amazing hard work of everyone in the Isuzu dealer network, and the team members who power the Isuzu products and stand by them day in, day out,” says Craig Uren, senior vice president: Revenue Generation at Isuzu.

During 2022, the South African bus, truck and van segments recorded combined total sales of 30 153 units, a 11.4% increase

supply of Isuzu trucks, while delivering excellent customer service and after-sales support,” explains Uren.

A preferred trucking solutions partner

compared to 2021, and the strongest industry performance peak since 2014. This is despite global and domestic supply chain issues that have impacted many sectors of the economy.

In the medium commercial vehicle (MCV) and heavy commercial vehicle (HCV) categories, overall industry sales grew by 17.8% and 19.6% respectively. In the especially competitive MCV slot, Isuzu’s truck sales increased by +10.12% compared to 2021, with HCV units sold rising by 0.24%.

“With such high demand for Isuzu products, it’s been our top priority to maintain a steady

A decade of class leadership in trucking

Trucks, especially Isuzu trucks, are forecast to have a first economic life before major overhaul of at least 10 years, with after-sales service provided via Isuzu’s dealer network.

The process starts with the optimal selection of the right vehicle for the job to achieve the lowest cents/kilometre performance over the long term. Custom-built cargo bodies also need to match the payload and work outputs required.

“Our consulting, vehicle selection, performance prediction and costing services are considerably enhanced by our association as full licensees of Truck Science TransSolve software. This enables Isuzu and our dealers to forecast trucking productivity with reasonable accuracy – a service that Isuzu fleet owners appreciate,” Uren explains.

Warranty support To help customers optimise their fleet utilisation, Isuzu has introduced optional Variable Warranty plans, specifically tailored to fit the needs of short-, medium- or longhaul operators. This opt-in plan extends the standard two-year, unlimited-kilometre warranty to either three, four or five years.

The Variable Warranty Plan is valid from the date of sale of a new vehicle to the original retail purchaser up to a maximum of 500 000 km on N-Series trucks, and 700 000 km on F and FX-Series trucks.

Maintenance terms and conditions apply to the specific Variable Warranty selected.

N and F Series The new-generation Isuzu N- and F-Series trucks have a gross vehicle mass (GVM) range from 4 200 kg to 8 500 kg and 11 000 kg to 26 000 kg, respectively. Then when it comes to towing and trailer operations, the N-Series caters for gross combination masses (GCM) ranging from 7 050 kg to 12 000 kg, and 16 000 kg to 36 000 kg for the F-Series.

An Isuzu FXZ 28-360 fitted with a Usimeca Brutus RC2221 compactor

58 IMIESA March 2023

VEHICLES & EQUIPMENT

An Isuzu NPR 400 configured as a crew cab pothole repair vehicle

An Isuzu FYH 33-360 8X4 fitted with a Liebherr 8 m3 mixer

The Isuzu GTR 24-240 truck tractor

business owners via its Ready To Work line-up of commercial medium and heavyweight trucks.

SMMEs who are well established, with a proven track record and pass a revised credit check process, have the option of a rental agreement off their balance sheet, which means it can be written off as a monthly expense and not an asset on their books.

“Isuzu’s Ready To Work portfolio of commercial vehicles showcases prebuilt trucks, with their applications, so business owners are able to generate revenue almost immediately. Coupled to our unique rental offer, this represents a game-changing moment for access into the trucking economy for small businesses,” says Uren.

The rental truck programme, formed in partnership with Isuzu Finance, provides peace of mind as ownership rests with the bank and qualifying small businesses pay a monthly rental based on the selected truck, application and period of the rental.

Businesses can choose between a minimum of 36 months and a maximum of 60 months.

The road ahead

There are also a wide range of transmission options, including Isuzu’s class-leading automated manual transmission (AMT). There are four N-Series models equipped with AMT, as well as six F-Series units.

Allison torque convertor transmissions are available in the Isuzu FV1400 while the newgeneration FVM 1200 moves up from a sixspeed ZF to a nine-speed ZF transmission.

The entire Isuzu truck range now comes equipped with tubeless tyres. The key advantage is cooler running, which helps to extend tyre life. Additionally, there’s less rolling resistance from a tubeless tyre, which reduces fuel consumption – lowering the total cost of ownership.

economy, Isuzu Motors South Africa is now also making commercial vehicle acquisition more accessible for entrepreneurs and small

Going forward, Uren says that Isuzu will continue building its capacity and capabilities to meet customer and industry requirements.

“We understand that South African customers deserve the best, which is what Isuzu delivers year in, year out,” Uren concludes.

Ready To Work In a bid to help start-ups gain traction in the

FYH 33-360 8X4 15 m3 tipper truck

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CEMENT & CONCRETE

Concrete technologists vital for preserving SA’s infrastructure

Natural disasters, along with maintenance backlogs, continue to threaten the condition and safety of South Africa’s infrastructure, prioritising the need for specialist skills.

60 IMIESA March 2023

I

n response, the Cement & Concrete SA’s School of Concrete Technology (SCT) has a range of training programmes to meet industry requirements. A prime example is the school’s five-day SCT30 Concrete Technology course, which will be presented five times in Midrand and once each in Cape Town and Durban during 2023.

The first SCT30 course in Midrand was held from 6 to 10 March, with the remaining four scheduled to run from 29 May to 2 June, 10 to 14 July, 11 to 15 September, and 13 to 17 November. In turn, the SCT30 progamme in Durban runs from 9 to 13 October, and the one in Cape Town from 20 to 24 November 2023.

Commenting on the need for these courses, John Roxburgh, senior lecturer at the SCT, says the provision of durable new infrastructure, as well as the competent maintenance and repair of existing infrastructure have become vital as climate change and global warming take their toll.

“Industry professionals and their employers have seen unprecedented devastation first-hand in recent years and months. A sound theoretical knowledge of concrete will enable construction practitioners to

CEMENT & CONCRETE

good concrete site practices – particularly curing requirements. Also, their concrete knowledge will help ensure that the concrete’s strength, durability and surface finish specifications are met,” he continues.

Course highlights

John Roxburgh, senior lecturer at the School of Concrete Technology

solve and prevent many problems – before they happen,” Roxburgh explains.

“They will be able to ensure that the specified concrete’s properties meet the needs of the size, shape and type of structure, and consider external ambient and internal thermal conditions. The professionals will be able to advise on placement techniques and other

The SCT30 course, which includes laboratory sessions, covers important aspects such as: • properties of concrete • concrete mix design and production • mix design for specialised applications • off-shutter and architectural finishes • formwork, reinforcement and join • defects, blemishes and repairs • mixing water and chemical admixtures • temperature’s effects on concrete quality • placing, compaction, protection and curing of concrete.

Professionals who successfully completed SCT30 can increase their concrete skills even further via more advanced training, culminating in the globally respected Advanced Concrete Technology (ACT) certification.

A universal need “Municipal and government departments dealing with infrastructural development, construction companies, cement producers, admixture suppliers, readymix concrete companies, concrete testing laboratories, precast concrete factories, structural consulting firms, architectural and quantity surveying businesses, as well as project development and management businesses these days cannot do without the input and services of a person competent in concrete technology,” says Roxburgh.

“Mining engineers would also benefit from this training for their certificates of competency and there is also the exciting and multifaceted field of decorative concrete to broaden the scope for concrete technologists.

In fact, our SCT30 course could be the launching pad for all industry professionals,” Roxburgh concludes.

For full details about qualification for SCT30, as well as other courses planned by the school in 2023, phone +27 (0)11 315 0300, email rennisha.sewnarain@cemcon-sa.org.za or visit www.cemcon-sa.org.za.

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IMESA MESA

IMESA AFFILIATE MEMBERS PROFESSIONAL AFFILIATES

CEMENT & CONCRETE AECOM siphokuhle.dlamini@aecom.com AFI Consult banie@afri-infra.com Alake Consulting Engineers lunga@alakeconsulting.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 CCG puhumudzo@ccgsytems.co.za / info@ccgsystems.co.za Corrosion Institute of Southern Africa secretary@corrosioninstitute.org.za Dlamindlovu Consulting Engineers & Project Managers info@dlami-ndlovu.co.za EFG Engineers eric@efgeng.co.za Elster Kent Metering Mark.Shamley@Honeywell.com EMS Solutions paul@emssolutions.co.za ERWAT mail@erwat.co.za ESCONGWENI BPH ENGINEERS (PTY) LTD info@escbph.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 Huber Technology cs@hubersa.com Hydro-comp Enterprises info@edams.co.za Infrachamps Consulting info@infrachamps.co.za INFRATEC info@infratec.co.za IQHINA Consulting Engineers & Project Managers info@iqhina.co.za iX engineers (Pty) Ltd hans.k@ixengineers.co.za JBFE Consulting (Pty) Ltd issie@jbfe.co.za JG Afrika DennyC@jgafrika.com KABE Consulting Engineers info@kabe.co.za Kago Consulting Engineers kagocon@kago.co.za Kantey & Templer (K&T) Consulting Engineers ccherry@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 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 Nyeleti Consulting naidoot@nyeleti.co.za Odour Engineering Systems mathewc@oes.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 gregl@sizabantupipingsystems.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 Southern African Society for Trenchless Technology director@sasst.org.za SRK Consulting jomar@srk.co.za Star Of Life Emergency Trading CC admin@staroflife.co.za TPA Consulting roger@tpa.co.za V3 Consulting Engineers (Pty) Ltd info@v3consulting.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 WRP ronniem@wrp.co.za Zutari Rashree.Maharaj@Zutari.com

The downside to quality shortcuts Weak economic conditions in construction have led contractors to find new ways of surviving, and some strategies could undermine the longevity of roads and buildings, says Avi Bhoora, executive: construction materials, AfriSam.

O

n the aggregates side, we find that the call for ‘brown’ material – as opposed to the high-value ‘blue’ material like quartzite, tillite and dolomite – is rising,” he says. “While some brown materials can be modified by additives, they cannot match the quality of competent rock.”

In the past, G1 aggregate was the main base course for roads, with G2 as the sub-base, and G4 and G5 used for the selected layers. Bhoora says that recently there are efforts to substitute these, using products with names like G4A or G4A Special, for instance. Specifications are being adapted possibly because of cost pressures but have not yet stood the test of time.

“During my 40 years in construction, I have been involved in projects building roads that have outlasted their expected 25-year lifespan by a decade or more,” says Bhoora. “It is uncertain whether the new specifications will be as effective, especially with the much heavier loads on our roads today. My personal view is that going this route might be short-sighted in the long run.”

Readymix trends In terms of the readymix market, he says the average strength of concrete supplied has been gradually declining. AfriSam has long been known in the sector as a specialist in high-strength products for demanding applications like high-rise buildings – with concrete strengths up to 100 MPa. “There are fewer projects like this currently, but there are also signs of users ‘buying down’ when it comes to readymix,” he says. “Whereas 35 MPa was the average strength we supplied until recently, that average is now closer to 28 MPa. This is concerning, as skimping on concrete strength is certain to have long-term consequences for buildings’ longevity.”

He notes that there is still insufficient work entering the project pipeline, holding back the potential of the construction sector to create jobs and build valuable infrastructure. Contractors and their supply chain remain under pressure, with low margins leading to the demise or amalgamation of important industry bodies.

With good-quality materials, roads have outlasted their expected 25year lifespan by a decade or more

AfriSam has long been known as a specialist in high-strength readymix products

IMIESA March 2023

63

WATERPROOFING

Sika SA adds Index range to local line-up membranes are reinforced with high areal weight, isotropic, thermally fixed, rot-proof, ‘non-woven’, single-strand spunbond polyester fabric. The reinforcement is very strong and has an optimal resistance to puncture and piercing. The product is ideally suited for scenarios where high mechanical resistance is required, such as foundations, car parks, water works, bridges, viaducts, tunnels and subways.

Dam linings

S

ika AG’s acquisition of a majority stake in Italian roofing and waterproofing systems manufacturer Index Construction Systems and Products in 2018 added a new dimension to the multifaceted solutions it provides worldwide.

Following this development, and effective from 1 January 2023, Index systems will now be exclusively available locally from Sika South Africa for standard flat-roof waterproofing, decorative, below-ground waterproofing and green roof waterproofing, all conforming to international standards.

“We felt the time was right for it to now form part of our existing roofing and waterproofing business in South Africa,” explains Paul Adams, managing director, Sika South Africa.

Examples from the Index line-up include

Installation of an Index bituminous membrane

Sika Index Topgum Biarmato, Sika Index Testudo, and Sika Index Fidia polyester and Fidia/V membranes.

Double reinforcing

In turn, Sika Index Fidia polyester and Fidia/V membranes are reinforced with a rot-proof, ‘non-woven’, polyester fabric composite stabilised with fibreglass mat, which is very strong and elastic, thus reducing the problems of the ‘banana effect’ and the retraction of head lap joints. The long-lasting strength, elasticity and stability at high and low temperatures make these membranes ideal for use as dam linings, plus single- or multilayer waterproofing systems for new building work or refurbishments.

Thanks to the addition of these and allied Index products, Sika’s cutting-edge technologies for the roofing and waterproofing markets are now even more comprehensive.

Sika Index Topgum Biarmato is a polymerbitumen waterproofing membrane with a double reinforcement consisting of rot-proof, isotropic, thermally stabilised, ‘non-woven’, polyester-fabric-strengthened fibreglass mat.

The long-lasting strength and elasticity at both high and low temperatures make this product ideal for use as a single- or double-layer waterproofing membrane for new building work or refurbishments.

Resistance to puncture and piercing An equally durable solution for niche applications, Sika Index Testudo waterproofing

An Index waterproofing solution for a building rooftop

INDEX TO ADVERTISERS APE Pumps AfriSam Bloc Contractors Cement & Concrete SA Endress+Hauser EnviroServ Waste Management Envitech Solutions GLS Consulting Grundfos Hall Longmore IMESA Krohne N&Z Instrumentation & Control

64 IMIESA March 2023

12 OBC 30 35 9 45 43 24 47 14 4, 18 & 62 41 27

Naidu Consulting Nextec NuWater Systems Rotocarb SBS Tanks Sealzed Group/Devac Infrastructure SMEC South Africa Structa Group Terraforce Vuka Group/Enlit Africa Xylem Zutari

20 17 OFC 22 IFC 61 49 33 51 IBC 2 50

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AfriSam Roadstab Cement is a high quality cement, specifically engineered and designed to reduce plasticity and enhance the strength and stability of road-based materials. In your hands, our advanced formulation ensures your effort is time well-spent.

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