Dr Alex Sinske, Adrian van Heerden, & Altus de Klerk, GLS Consulting
using labour-enhanced methods. The project has also achieved another landmark, being the first CRCP construction in South Africa to be executed under the new Committee of Transport Officials (COTO) specifications. P8
IN THE HOT SEAT
Flexible pavement construction forms an essential component of local and global transportation networks. IMIESA speaks to Rory Botha, Managing Director of Bitumen Supplies and Services (BSS) and allied entity, Global Road Binders, about how the Group’s strategy will ensure that bitumen as the essential ingredient is always available on demand within the SADC region and South Africa. P12
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EDITOR Alastair Currie
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DESIGNER Beren Bauermeister
CONTRIBUTORS Adrian van Heerden, Dr Alex Sinske, Altus de Klerk, Amanda Filtane, Burgert Gildenhuys, Chris Campbel, Deon van Zyl, Richard Matchett, Sibusiso Mjwara
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.
epending on where you reside – coastal or inland – you may have the privilege of living within naturally beautiful surroundings, but you don’t have to look far to witness the evidence of environmental damage. It’s everywhere and a growing pollution threat. Contributing factors include extensive erosion, littering, dysfunctional wastewater treatment plants, inadequate stormwater management, and illegal dumping of domestic/hazardous waste. They all contribute to negative river heath, with downstream consequences. Then there’s the climate change factor, which continues to exacerbate the problem. The fact that the world is getting hotter, and the weather more unstable is beyond scientific dispute. So, greener interventions are needed. However, the overriding priority is our living experience, which needs to balance socioeconomic priorities with environmental ones in terms of the United Nations Framework Convention on Climate Change objectives. Reaching net zero 2050 targets is certainly challenging, underscored by South Africa’s Just Energy Transition (JET) from coal-fired energy in favour of renewables. Interrelated communities, businesses and Eskom need time to prepare and adjust, backed by progressive international JET funding support.
The question is: what can we do right now to combat and mitigate climate impacts? Essentially, it’s a mindset change that is interdependent on proactive engineered outcomes, municipal leadership, adherence to environmental legislation, and social education.
Separation at source
Let’s take separation of waste at source as an example. While there are proactive examples among households and industry, the practice is still far from widespread. The bulk of our domestic solid waste still goes to landfill, including e-waste, which certainly shouldn’t in terms of Extended Producer Responsibility stipulations. And where e-waste dumping still occurs, it’s a loss both in terms of recycling and job creation, as well as being a source of serious contamination.
However, South Africa is not unique when it comes to gaps in e-waste stewardship. This is illustrated by the UN’s Global E-waste Monitor 2024, which reports that electronic waste is rising five times faster than documented e-waste recycling. This is concerning considering that some 62 million tonnes of e-waste was produced
globally in 2022 and is expected to climb to 82 million tonnes in 2030. There’s a similar trend for non-recycled waste in general.
Practical considerations driven by infrastructure
For developing countries with adequate financial resources, there’s no excuse not to recycle. However, in South Africa we need to appreciate that sustainability may not be an immediate priority, given the high levels of unemployment and poverty. For many, the first goal is to meet day-to-day needs. Clearly, that’s also not sustainable if we want to build an inclusive economy where everyone has a job, a formal serviced dwelling and an opportunity to grow with vision.
It all comes back to enabling infrastructure – whether it’s grey, green or blue. Grey infrastructure examples include roads and dams, while blue interfaces with green by delivering water-based elements like engineered canals, ponds and stormwater attenuation systems that respond to climate change issues.
In addition to protecting the environment and promoting healthy living, implementing these initiatives creates jobs, a sense of communal ownership, and a commitment to conservation practices.
A positive step in this direction is South Africa’s new project preparation bid window initiative recently unveiled by the Department of Public Works and Infrastructure, and Infrastructure South Africa (ISA). This is specifically aimed at projects above R1 billion that have the potential to crowd in investment from non-fiscal sources.
The application deadline is 6th December 2024. Selected projects will then receive comprehensive ISA project preparation assistance – a key factor for successful implementation. This includes funding structuring support, technical and legal support, and regulatory compliance studies.
Priority projects considered include those in the energy, human settlements, municipal infrastructure, transportation, water and sanitation segments. Hopefully, those approved will unlock a fresh pipeline of active projects that will help accelerate both our blue-green and sustainable development goals.
We sell heavy forklifts and container handlers to the Ports Industry
Engineering liveable and healthy cities
Within the developed and developing world, the pressing issue of climate change mitigation and adaptation unites us, as does the universal role of municipal engineers and allied built environment professionals in responding to the challenges.
This viewpoint was reinforced at the recent Future Green City World Congress, held during September 2024 in Utrecht, the Netherlands. Visitors from around 60 countries came together to share their experiences and knowledge, with presenters showcasing a host of innovative solutions to enhance our urban living experience. Along with IMESA Deputy President, Bhavna Soni, I had the privilege to attend and to represent South Africa as a country member of the International Federation of Municipal Engineering (IFME), the latter being a co-organiser of the event.
IFME and AIPH Awards
A highlight was South Africa’s recognition amongst its peers as a pathfinder in green interventions by winning the Development Projects (non-Construction) Category at the IFME 2024 Excellence Awards. Our winning entry was the Transformative Riverine Management Programme submitted by eThekwini Municipality.
Another highlight at the Congress was the International Association of Horticultural Producers’ (AIPH’s) World Green City Awards Ceremony 2024. The latter recognises the role of city authorities in promoting and supporting the greater inclusion of plants and nature in urban environments.
There were three finalists competing for an award in each of the seven entered categories, with the winning entries originating from Australia, China, Brazil, Kenya, Mexico and Romania. Notably, two South Africa projects were finalists in the Living Green for Biodiversity and Urban Ecosystem Restoration Category. These comprised eThekwini Municipality’s Community Reforestation Programme, and the City of Tshwane’s Pretoria East Urban Biosphere Reserve project. While neither won an award, making it that far was a tremendous achievement, given the tough competition.
However, it was great to see Kenya’s Mandera Municipality winning the Living Green for Climate Change Category for its Greening Programme –an outstanding one that could be replicated in South Africa.
Mandera Municipality’s initiative involves systematic tree planting, supported by critical water infrastructure (namely underground and elevated storage tanks) to enable sustainable forest growth within a semi-arid landscape where recurring droughts are common. Another key
feature is community involvement, with around 1 300 participants employed – largely represented by women and youth from surrounding communities. Local schools are also part of the programme’s success through education and tree nurturing endeavours that all contribute to a cooler and more weather resilient environment.
Utrecht Commitment
Irrespective of the scale, greening urban spaces does make a major difference, which was the motivation for the signing of the Utrecht Commitment at the Congress. The latter is a joint agreement between IFME and World Urban Parks to work collectively as municipal engineers and green professionals to prioritise nature-based solutions, plus policies that prioritise environmental sustainability. These are all initiatives that align with IMESA’s mandate.
Let’s face it, traditionally grey infrastructure is designed to be functional. However, with creative thinking, green elements can be included. An example is the provision for vegetated pathways on bridges for wild animals, which was one of the case studies presented in Utrecht – itself a shining example of sustainability in action.
Like other cities globally, Utrecht faces intensified urbanisation, and rising temperatures that
contribute to increased urban heat unless effectively countered. Utrecht’s response is a comprehensive programme defined by its Healthy Urban Living for Everyone strategy.
That has translated into the widespread application of green building construction, renewable energy, new parks, rooftop gardens, plus a shift to electric vehicles. However, when it comes to mobility, the preferred mode of transport for most are bicycles thanks to enabling infrastructure. In fact, it was remarkable during my visit to see so few cars on the road, and to see even city officials cycling to the Congress.
Handing over the baton
The latter is a great illustration of leading by example, which has also been my objective as IMESA’s President for the 2022-2024 term, concluding in November – ably supported by our exceptional EXCO, Council and Head Office personnel.
As IMESA, we have a long and proud history dating back to the early 1900s. Along the way, each successive President has built on this legacy, fostering an environment for innovation and excellence among its members. Now, given our unique development challenges, climate change, as well as a growing infrastructure backlog, IMESA’s role has become even more relevant.
As a result, over the past two years IMESA has focused on strengthening its alliances with key stakeholders that include allied Voluntary Associations and ECSA. Through our lobbying efforts, we’ve also been invited to collaborate with strategic government entities. This recognition is welcomed since it’s a vital progression for IMESA as an enabler of municipal engineering excellence, founded on mentorship and professional development. I’m making my own personal contribution as a registered ECSA mentor.
As showcased at the Congress, leading cities succeed when they embrace engineers as strategic partners. That’s why IMESA will increasingly be a core part of South Africa’s successful and sustainable evolution going forward.
IMESA entry wins category award and global recognition 2024 IFME EXCELLENCE AWARDS
Coinciding with the Future Green City World Congress in September 2024, the International Federation of Municipal Engineering’s (IFME’s) 2024 Excellence Awards served to showcase outstanding achievements in sustainable design and execution. South Africa was among the winners.
The overarching objective of the IFME Excellence Awards is to recognise outstanding municipal projects across two categories, namely Construction Projects and Development Projects (non-Construction). Each project is scored against seven criteria in alignment with the United Nations Sustainable Development Goals.
Additionally, entries must meet IFME’s global objectives in terms of innovation and creativity in municipal engineering; environmental benefits for the community; transfer potential to other municipalities or countries; as well as successful project outcomes.
Fourteen project nominations were received from seven IFME member countries (two submissions, one in each category) comprising Australia, China, New Zealand, Norway, South Africa, Sweden and the USA. In turn, fifteen judges representing nine IFME countries assessed the submissions, with eight assigned to the Construction category and seven for the Development category.
As for previous IFME competitions, the standard was extremely high across the board, but ultimately it came down to a
unanimous decision, and the following are the winning projects:
CONSTRUCTION PROJECTS
WINNER
Country: China
Project: Xiamen Mountains-to-Sea Trail
Entry submission: Xiamen Municipal City Development & Construction Co., Ltd.
Description:
Dedicated to achieving greenness, low carbon, health and ecological balance for the city, the Xiamen urban slow road has so far presented two footpaths – the Cloud Line that links the east and the west of Xiamen and the Forest Line that links the south and the north. The two footpaths, totalling 54 km in length, provide citizens and tourists with a space where they can enjoy healthy recreational activities, get close to nature, move through landscapes with mountains and water features, and appreciate both the urban and green spaces.
HIGHLY COMMENDED
Country: Sweden
Project: The Harbor Bath, Gothenburg
Entry submission: Exploateringsförvaltningen (The Development Administration), City of Gothenburg
Description:
Gothenburg is working hard to create a city centre full of life. The shores of the river Göta älv is key to this process. The goal is to have more people living in the city centre and more visitors. The old shipyard areas and allied zones have now been transformed with this objective in mind. An important part in this work is The Harbor Bath. Its importance is underlined by the fact that Sweden’s King and Queen attended the opening ceremony.
Durban’s Transformative Riverine Management Programme (TRMP) aims to enhance the city's resilience to the impacts of climate change through the rehabilitation of 7 400 km of Durban’s degraded rivers and streams to optimise ecosystem services, with social and local economic benefits. The transformative climate adaptation approach incorporates nature-based solutions, community ecosystembased adaptation, and green/circular economy
IFME country representatives accepting their 2024 Excellence Awards. On the far right is IFME President Sanne Hieltjes from the Netherlands
Construction Projects Category Winner: Xiamen Mountains-to-Sea Trail, China
considerations, with the intent to scale-up existing riverine management initiatives.
HIGHLY COMMENDED
Country: Finland
Project: Strengthening the heartbeat of a billion+ people in public areas by 2030
Entry submission: Lappset Group Ltd
Description:
Public works and areas are commonly carried out by private sector providers. The Finns want to encourage not just one project, but long term
aims and dreams for enhancing wellbeing and everyday life for people of every age. Deep collaboration with globally known entertainment products (i.e., Lego, Peter Rabbit, and Mattel) theme parks encourage children to move and get rid of their mobile phones for a moment. Is there a better way to foster UN’s goals globally?
IMESA in the spotlight
Representing South Africa, IMESA President Sibusiso Mjwara, and IMESA Deputy President Bhavna Soni, attended the Future Green City
Development Projects Category Winner: Transformative Riverine Management Programme (TRMP), eThekwini Municipality, South Africa
World Congress and IFME Awards event, held in Utrecht, the Netherlands.
“This was certainly a proud moment, and as IMESA we’d like to congratulate our EXCO member, Geoff Tooley on his winning submission,” says Mjwara. “As the Senior Manager: Catchment Management Engineering Unit for eThekwini Municipality, Geoff is leading a pioneering approach to TRMP implementation – a vital initiative with opportunities to replicate this successful model across South Africa and incorporate lessons learnt from around the world.”
“Being part of the IFME community provides an exceptional platform for knowledge sharing and advancing the strategic role of municipal engineers. Together, we can positively shape South Africa’s and the global infrastructure landscape for our collective sustainable future,” Mjwara concludes.
In a pioneering upgrade project on the N3 highway in KwaZulu-Natal, contractor Rumdel has partnered with construction materials leader AfriSam to apply continuously reinforced concrete pavement (CRCP) technology – using labour-enhanced methods.
Local companies were contracted and given the necessary training, supervision and mentoring to conduct work to the required quality standards
N3 sees pioneering work in labour-intensive concrete roadworks
The project therefore meets two important priorities of the client, the South African National Roads Agency Limited (SANRAL): ensuring the durability and longevity of South Africa’s national highways, while leveraging the job creation potential of the country’s infrastructure development. According to Kanyiso Nqabeni, Construction Manager at Rumdel, the project has also achieved another landmark, being the first CRCP construction in South Africa to be executed under the new Committee of Transport Officials (COTO) specifications.
“This added further complications to the contract, requiring a collaborative response from Rumdel and AfriSam,” says Nqabeni. “There was certainly a steep learning curve to find solutions, but through regular and open communication we
were able to address pain points and apply the necessary corrective action.”
For instance, the COTO guidelines limit the application of hand-enhanced concrete work to a minimum – preferring mechanical pavers for placing concrete on roads. The project team therefore had to apply its combined experience to ensure that the work could be conducted at a reasonable speed while accommodating the training of manual workers.
Scope of works
The project is overhauling and reconstructing the N3 over a distance of 4,6 km between the Ashburton and Lynnfield Park interchanges, according to Project Site Agent Andrew Robinson.
The upgrade from jointed concrete pavement (JCP) to CRCP involved redoing the bulk earthworks and layer works, and the construction of a cement-stabilised, 300 mm C3 layer using G2 material from AfriSam. This was followed by an interlayer of recycled concrete from the
project, on top of which was constructed the 250 mm thick CRCP between December 2022 and May 2024.
“CRCP is not in itself new to the local construction industry, but the use of manual labour instead of mechanical pavers was a new approach,” says Robinson. “The contract as a whole has been able to employ about 680 people, of which 120 to 150 were dedicated to the CRCP aspects.”
To carry out the placing and compaction of concrete for the CRCP layer, Rumdel procured five subcontractors – each of which employed 24 to 30 workers.
“This represents significantly more labour than we would have required if we used traditional paving equipment,” he explains. “For instance, the average team associated with the use of a single paving machine would generally not exceed 12 to 15 people.”
While the labour-intensive methods did provide welcome employment opportunities in the area,
This is the first project in South Africa to use labour-intensive methods on CRCP work of this scale
AfriSam supplied a total volume of 50 250 m3 of readymix concrete for the CRCP
The project is a complete overhaul of the N3 between the Ashburton and Lynnfield Park interchanges – a distance of 4,6 km
Deliveries were made over a period of 205 days between March 2023 and May 2024 with 200 m3 to 600 m3 of concrete poured each day
the work itself was arduous – especially in the heat of summer. A total volume of 50 250 m3 of concrete for the CRCP – supplied by AfriSam from its nearby Umlaas Road facility – had to be manually handled and spread, highlights Nqabeni. Adding to this onerous task was the large aggregate size used in the mix, whose weight made it even more difficult to shovel the concrete.
“In a labour-intensive project that dealt with such high volumes of concrete, Rumdel’s primary concern was to manage the health, safety and workload of each CRCP team,” he says.
The working day was therefore split into three shifts, with a different team for each shift. The first team would work from 05h00 to 10h00, the second team would take over until 15h00, and a third team would complete the day. Where possible, the project’s daily working schedule on the CRCP avoided the hottest times of the day between 11h00 and 14h00.
Readymix methodology
The high daytime temperatures also affected the setting time of the readymix, so AfriSam built these considerations into its mix, according to Xolani Mbatha, AfriSam’s Regional Product Technical Manager for construction materials.
“In addition to the normal water reducing admixtures to ensure longer workability, we also used chilled water in the mix when necessary,” says Mbatha. “This helped to slow down the reactivity of the concrete under high temperature conditions.”
The heat also called for special measures to reduce surface evaporation from the newly laid CRCP. Robinson explains that Rumdel applied mist sprayers to keep the temperature down on the concrete surface.
“Adjustments were also made in the application of curing compound, to reduce evaporation,” he says. “The compound was applied in two phases: once as concrete was discharged, and again after the concrete had hardened sufficiently for the surface to be textured.”
To protect the curing concrete against thunderstorms during the rainy season from November to April, plastic “tents” were placed over the pavement. This ensured that the specified riding surface could be achieved.
In delivering the required quantities of concrete for the rollout of the CRCP, AfriSam supplied its readymix over a period of 205 days between March 2023 and May 2024, according to Randal Chetty, AfriSam’s Regional Sales Manager.
This N3 upgrade is the first CRCP construction in South Africa that has been executed under the new Committee of Transport Officials (COTO) specifications
“The production cycle required the pouring of between 200 m3 and 600 m3 of concrete each day, with our Umlaas Road batching plant capable of producing 40 m3/hour,” says Chetty. “Timing was vitally important to balance to volume requirements of the CRCP with the open time of the concrete mix.”
He adds that this also required considerable flexibility from both contractor and supplier, with concrete pours starting as early as 04h30 and ending as late as midnight, to accommodate the complexities of the project schedule.
Bridge reconstruction and stormwater
In addition to the roadworks, the contract also involves the reconstruction of two bridges. The Lynnfield Park bridge was demolished and reconstructed, creating a wider structure for the area’s growing traffic volumes. The bridge over the Mpushini Spruit was also widened, requiring the deck to be demolished and rebuilt, with modifications applied to the abutments.
A permanent median barrier is being constructed from readymix supplied by AfriSam, as well as ancillary works such as v-drains and catch-pits. The project’s scope includes the upgrading of 2 km of the R103, which passes underneath the N3 at the Lynnfield Park interchange, as well as the interchange itself. Work includes the construction of mechanically stabilised earth walls in high fills, as well as large concrete retaining walls in cut embankments.
A CASE STUDY IN WATER DEMAND FORECASTING
Integrating advanced statistical regression with traditional methods
Revenue water demand forecasting in large Southern African cities can be used for ensuring sustainable urban water management. As a case study, 10 years of city-wide monthly water demand data of a large metropolitan area was processed to estimate future growth areas. By leveraging statistical analyses, the explorative study attempted looking at patterns and trends that can guide decisionmaking for city planners and utility managers. By Adrian van Heerden, Altus de Klerk and Dr Alex Sinske
The purpose of this case study was twofold: to enhance revenue by improving water resource allocation, and to support long-term master planning for the city’s infrastructure development. With accurate forecasting, the city could potentially proactively address future demand surges, while optimising its financial resources.
Approach
To access historic meter data from individual stands within the city, Swift™ was utilised to extract monthly readings. This tool allowed for the identification of clock-overs, gaps, and other errors within the data, which were then systematically fixed to ensure the integrity of the dataset. Swift proved instrumental in cleaning up inconsistencies that may have skewed
the analysis, providing a more accurate and reliable foundation for further statistical modelling.
After cleaning the data, only stands with complete records for the entire 10-year period were retained for analysis. This approach ensured the consistency and reliability of the data, though it highlighted a key challenge – the limited availability of high-quality, long-term data. Many records were incomplete or had discrepancies, underscoring the difficulties faced in making informed, data-driven decisions for forecasting in large-scale water demand planning. To better compare the demand across stands of varying stand sizes, the data was unitised into a demand per square metre metric. By normalising the data in this way, the analysis allowed for a more consistent comparison of changes in water demand regardless of the individual stand area. This transformation enabled a consistent assessment of
demand patterns and growth trends across the city for various land use categories, offering a clearer perspective on water usage behaviours and future forecasting needs.
Autoregressive Integrated Moving Average (ARIMA) models are a popular and powerful tool for forecasting time series data, such as sales, prices, or weather. It captures the patterns and trends of the data using a combination of past values, differences, and errors.
An extension to ARIMA that supports the direct modelling of the seasonal component of the series is called Seasonal Autoregressive Integrated Moving Average (SARIMA). Although machine learning offers potential for more refined forecasting, the existing methods, such as SARIMA, have shown promising results when looking holistically at a large metro, especially considering the interplay of environmental factors and evolving socio-economic conditions.
Output
The SARIMA model was employed to perform water demand forecasting on the dataset. The model utilised a seasonal period of 12 months, capturing recurring patterns in water consumption throughout the year for each stand or area. This time-series approach allowed for the detection of both trend and seasonality in the data, essential for predicting future demand in a highly variable environment like urban water use.
To ensure the accuracy of predictions, each stand or suburb was individually calibrated to minimise the Root Mean Square Error (RMSE) – a measure of prediction accuracy. However, the results indicated lower correlation values when looking at individual stands, as the demand variability from one stand to another is often difficult to predict with precision. In contrast, much better correlations were achieved when aggregating data at the suburb level or by combining similar land uses. This suggests that water demand is more predictable on a collective scale rather than on an individual stand basis.
When looking at the entire city (as shown in Figure 1), the SARIMA model produced highly accurate forecasts of the last 12 months compared to actual data, further emphasising that predicting demand at a macro level is generally easier than at the micro level. The aggregated data smooths out irregularities and local anomalies, providing a clearer picture of overall trends.
However, some land uses proved more challenging to predict accurately – specifically, industrial areas, government facilities, and parks exhibited higher variability, making them more unpredictable.
Dr Alex Sinske, Head of Technology, GLS Consulting
Altus de Klerk, civil engineer, GLS Consulting
Adrian van Heerden, civil engineer, GLS Consulting
FIGURE 1
Similarly, densely populated areas like the central business district struggled to achieve good correlation due to their complex, fluctuating water demand patterns. These findings highlight the need for more nuanced models when dealing with specific land use categories and densely populated regions.
The dip in water consumption shown in Figure 2 aligns with the event of low rainfall in the region during 2015 according to the Annual State of the Climate 2021 by the South African Weather Service (2022).
Insights
The insights gained from this water demand forecasting analysis provide a wealth of opportunities for improving urban water management. One of the most immediate applications is the ability to prioritise future infrastructure upgrades, considering CAPEX and OPEX budgets are often severely constrained.
By identifying areas with growing or erratic demand patterns, city planners can strategically allocate resources to ensure that upgrades are focused where they are needed most. Additionally, this data can serve as a sanity check for ongoing or planned projects, confirming whether investments align with actual usage trends and projected future demand. This information can also be instrumental in improving future analyses.
By refining models and incorporating insights from this study, future forecasting can be even more accurate and actionable. Furthermore, the ability to detect regions where water demand is changing in unexpected ways can help trigger early investigations or studies. Understanding why certain areas deviate from expected demand patterns may reveal underlying issues – such as infrastructure leaks, rapid densification and population growth, or shifts in land use that require further attention.
Another important application of this data is identifying areas where increasing demands are placing additional stress on an already burdened water supply system (as shown in Figure 3). By proactively addressing these regions, the city can avoid potential shortages or service disruptions, ensuring sustainable water delivery. Moreover, this analysis can inform modifications to tariff rates. Suburbs or land uses showing signs of increased and potentially wasteful water consumption can be targeted with adjusted rates, encouraging more efficient use of water resources. This proactive approach can help the city manage demand more effectively while promoting responsible usage among residents and businesses.
Conclusion
While the current approach to water demand forecasting provides satisfactory results, future improvements could focus on several areas. Incorporating environmental variables, such as rainfall and temperature, could enhance model accuracy by accounting for external factors influencing water demand. Additionally, exploring
References
[1] GLS Consulting, Swift, www.gls.co.za/software/products/swift.html Accessed 1 Oct. 2024. [2] South African Weather Service, Annual State of the Climate 2021, 4 Apr. 2022, www.weathersa.co.za/Documents/Corporate/Annual%20State%20of%20the%20Climate%20 2021_04042022114230.pdf. Accessed 1 Oct. 2024.
advanced machine learning techniques, like neural networks or ensemble models, may improve the precision of predictions. Increasing the granularity of data collection, with daily or hourly readings, could also help capture short-term demand fluctuations and enhance model responsiveness.
It is worth noting that although machine learning is a powerful tool for analysing patterns, making predictions, and automating complex tasks, it could become problematic if the data used is of low quality or limited in scope. Algorithms trained on incomplete, biased, or inaccurate data may produce unreliable or skewed results, leading to poor decisionmaking. Additionally, with insufficient data, models may overfit – becoming too specific to the training set. Hence, the quality and diversity of data are crucial for safe and effective machine learning applications.
To ensure high-quality data for machine learning, improvements in data collection processes are essential. Adopting robust data validation and cleaning protocols can help eliminate errors, inconsistencies, and duplicates in the dataset. In this regard, Swift was essential in providing a reliable basis. Regular audits and feedback loops are vital to continuously monitor the quality of the data and adapt data collection and processing practices.
In summary, combining machine learning with traditional forecasting methods offers a solid foundation for accurate water demand predictions. As data quality and environmental insights continue to improve, these models can be refined to ensure a resilient and efficient water supply system for growing cities in Southern Africa.
www.gls.co.za
FIGURE 2
FIGURE 3
On-site PMB manufacturing in Zambia with over 25 000 tonnes supplied in the last 36 months
BSS AND GLOBAL ROAD BINDERS
BITUMEN SUPPLY ON TAP REQUIRES EXPERTISE AND LOGISTICS
Flexible pavement construction forms an essential component of local and global transportation networks. IMIESA speaks to Rory Botha, Managing Director of Bitumen Supplies and Services (BSS) and allied entity, Global Road Binders, about how the Group’s strategy will ensure that bitumen as the essential ingredient is always available on demand within the SADC region and South Africa.
What is your track record to date in the roads market and what sets the Group apart from its competitors?
RB As the holding company, BSS has been a family-owned business for 29 years with a wide footprint on the African continent, supplying road binders in approximately 17 different countries at any given time.
We supply a full range of road binder products for the local and African export market, which enables our clients to source their requirements from a reputable, sustainable supplier with a longstanding history of offering quality materials that meet all engineering specifications.
Our primary focus from inception was on supplying the export market into Africa. However, the series of refinery closures in South Africa in recent years led to a decision to enter the RSA market to supplement the shortfalls being experienced in terms of supply and demand.
In terms of the business model, BSS focuses on African exports, while Global Road Binders concentrates on South African bitumen supply orders. Combined, these entities – collectively employing over 100 skilled personnel – contribute a major portion of overall bitumen volumes in these regions.
What is the status of bitumen production globally?
There’s been a clear shift within the worldwide refining fraternity towards an increasing focus on the production of white products, such as petrol, diesel and paraffin, due to their higher profit margins. In certain instances, this has resulted in the decline of bitumen production (defined as a black product), because it doesn’t translate into the equivalent profitability yields. However, despite this, the upside is that there are still major players in the bitumen refining industry globally dedicated to supporting road infrastructure development, which is a universal priority.
Given the changing market patterns, we have capitalised on longstanding supply arrangements with leading bitumen refiners internationally
– developed over close to three decades – to ensure that South Africa and SADC remain high on their list.
Our past relationships with them have been very valuable in fulfilling our current intention of being a major and sustainable supplier to our end markets. Apart from the commercial rewards, we are very pleased to be able to contribute to ensuring a guaranteed supply of quality materials that enable the construction of quality road pavements essential for enhanced socioeconomic growth and ever-increasing traffic volumes.
Given South Africa’s increasing reliance on imports, what are the implications for the roads industry?
The implications are problematic as you require a mindset change. You can no longer go to a local
BSS has concluded formal ship charter contracts. The Ianthe vessel shown here arrives in Durban every month to transfer bitumen to BSS’s nearby storage facility
Rory Botha, Managing Director of Bitumen Supplies and Services (BSS) and allied entity, Global Road Binders
refinery (the one exception being Sasol’s Natref refinery for the time being) and uplift product.
Aside from rand/dollar price fluctuations, there are now also potential quality issues to safeguard against within industry when it comes to which bitumen imports to procure. Locally produced bitumen has always met the highest global standards. Now checks and balances need to be in place to ensure that South African contractors are buying compliant products. From BSS’s standpoint, we guarantee that all bitumen products we import meet local and international specifications.
Where are the bulk of your bitumen imports sourced from?
We have various formal relationships with major foreign based refiners. These include Bapco Refining in the Kingdom of Bahrain, and National Refinery Limited in Pakistan. Both are world class leaders in their field.
What forms of quality assurance do you provide?
As a standard quality assurance protocol, BSS conducts a full BT 1 and PG grading on every vessel arriving with our imported products, as well as Geochem testing at the port of loading.
How are you responding to the logistics challenges in South Africa?
As a reliable supplier, we ensure that imported products are ordered well in advance, and then stored ready for upliftment by local road contractors and asphalt producers. We already have extensive experience in this area thanks to our operational track record in Africa. These are regions where there are no local refineries. So, it’s a case of replicating and expanding the model in South Africa.
It is a complex logistical process, which we must anticipate in conjunction with our clients and mitigate against potential bottlenecks. Having adequate storage capacity is key. In response, BSS has invested in additional storage at our fixed facilities neighbouring the port cities of Cape Town, Durban, and Gqeberha, as well as our inland supply base in Vanderbijlpark, with provision made for future expansion. We have also concluded formal ship charter contracts to ensure we have sufficient capacity to supply our requirements from these centres.
Within the SADC region, we have facilities in Lilongwe, Lusaka and Windhoek. The latter include mobile bitumen emulsion plants and mobile polymer modified bitumen (PMB) plants to service SADC customers, which are often based in remote areas. However, in South Africa we primarily concentrate on bitumen supply.
Are their greener solutions in the pipeline in terms of bitumen product research?
BSS is very proud to have been involved with ongoing research conducted by various organisations on greener options. A prime example is an initiative in conjunction with the University of Pretoria and the CSIR on introducing recycled plastic into binders for asphalt pavements.
Going forward, we would prefer to see more bitumen emulsion used as it’s a less aggressive
One of the Group’s trucks offloading from a chartered vessel using a ship to truck gantry
product and more environmentally friendly in terms of climate change impacts. This, however, is largely incumbent on the design engineer to specify.
What are the benefits of being a Sabita member?
Being a member of the Southern African Bitumen Association (Sabita) reinforces our commitment to the highest industry standards, adherence to quality, and engineering standards. BSS has been a proud member of Sabita for the last 29 years and has our full backing. We are excited to support this crucial organisation to ensure that the South African bitumen sector remains world class in the face of evolving market challenges.
Is the bitumen import trend now a permanent feature for South Africa?
This is a 100% certainty, and the demand for imports will become even greater, if Natref stops supplying bitumen locally.
And in closing?
We have enjoyed developing our market share in Africa as an exporter over an extended period and now look forward to the prospect of applying this experience increasingly in South Africa. Rather than creating a vacuum, South Africa’s shift to bitumen imports opens up a whole new world of opportunity.
THE CONTEXT AND ORIGINS OF CAPITAL EXPENDITURE PLANNING AND BUDGETING IN SOUTH AFRICA
Before introducing the Municipal Finance Management Act (MFMA) in 2003, local governments in South Africa were not required to draft separate capital budgets. Although most did, these budgets had no formal status and their importance for effective financial management was not recognised. Without a separate capital budget, there was a risk that high-cost capital projects might be unfairly prejudiced against in favour of operating expenditure, potentially shelving essential projects. By
The introduction of the MFMA was a significant turning point, requiring municipalities to develop long-term capital budgets, implement rigorous project feasibility analysis, and regularly report on their financial performance. The MFMA also introduced financial management tools such as GRAP, IDP, and MTREF to support effective
Burgert Gildenhuys*
capital budgeting. In turn, the Spatial Planning and Management Act (SPLUMA) introduced the notion of developing capital expenditure frameworks (CEFs) as part of municipal spatial frameworks.
The process of reaching the stage where CEFs became a focal point of spatial planning developed historically through three broad and distinct phases.
These comprise the policy development, legislative, and implemention phases. There are some overlaps, but they are also marked by different terminology and often conflicting interpretations between national departments.
This article provides a short history of how capital budgeting developed in the local government sphere through this phased progression over the past three decades, with reference to key milestones.
1990
TO 2000:
POLICY DEVELOPMENT PHASE
World Bank Reconnaissance Missions: 1991, 1992 and 1993
This was the first time the investment demand to address service backlogs was quantified for the metropolitan regions in South Africa. The visits aimed to identify critical issues in formulating national policies on urban development. The following three main themes emerged:
• The disparities in access to and levels of services available to the large majority of the urban population;
• The disparity in the economic and fiscal base of the black and white cities, and the need to unify the metropolitan areas politically, administratively, functionally and financially to address redistributive requirements and create requisite levels of efficiency, equity and capacity in the provision of urban services; and
• The underlying human costs and economic inefficiencies in the current spatial structures of the cities, and the need to reverse the continuing extensive process of urban growth to consolidate the urban areas socio-economically and spatially. These missions undoubtedly laid the groundwork for policy and legislative
development of the local government system over the next decade.
De Loor Task Group, 1992
As part of SA's national housing policy development process, it was the first time that housing and infrastructure demand for South Africa was modelled at a national scale. Infrastructure investment modelling became a feature of the subsequent work done by the World Bank in South Africa and the quantification of inputs into the Municipal Infrastructure Investment Frameworks between 1994 and 2007. Influenced by the World Bank Reconnaissance Missions to South Africa in early 1990, the technical work regarding service levels and housing remained largely intact in the Reconstruction and Development Programme (RDP) released by the ANC in 1994.
The RDP, 1994
The RDP was the election manifesto for the ANC that became the basis for municipal service delivery in South Africa. The emphasis was on access to basic services, and the concept was eventually included in the Constitution.
DBSA: 20 Towns Study, 1995
This was the first technical analysis of the link between capex and opex for delivering infrastructure services in South Africa. This document laid the basis for most subsequent modelling and quantification
of capex and opex for infrastructure investment.
The MIIF: 1995 to 2007
The Municipal Infrastructure Investment Framework (MIIF) addressed municipal service delivery at a strategic level with the same objectives and intent as the current CEFs. It quantified the implications of the RDP policy in terms of service numbers, capital requirements and operating consequences.
The MIIF went through seven cycles until 2007 and provided an in-depth technical analysis of the financial (capex and opex) implications of different service delivery policy options. It has a 10-year window. The tool used in the MIIF was, however, focused on testing policy outcomes rather than planning for infrastructure and service delivery.
White Paper on Local Government, 1998
There was a strong emphasis on access to basic services from a health and safety perspective and private sector investment and funding. The White Paper promoted and saw infrastructure investment planning as an integral part of the future municipal system. All the subsequent municipal government legislation flowed from the White Paper.
The White Paper framed the concept of “developmental local government”, which gave rise to the notion of integrated development planning (Section 3), which
Burgert Gildenhuys, Director, BC Gildenhuys & Associates (BCGA)
found its way into legislation through the Municipal Systems Act of 2000 (Act 32 of 2000).
1998
TO 2003: THE LEGISLATIVE PHASE Municipal Demarcations, 2000
South Africa has a strong history of rural and urban local governments responding to local issues. Up to 2000, all policies and strategies had an urban bias. Although recommended by the author in the 2000 review of the MIIF, policies were never reviewed to adapt to the new local government dispensation.
One of the challenges is that we deliver services to regions based on uniform urbanbased national legislation and regulations, which are not always appropriate to local conditions and the ability to address local problems.
COGTA development of the MIG allocation formula, 2000
In 2000, the government's capital grant system was revised, and it developed the Municipal Infrastructure Grant (MIG) formula for grant allocation through the Division of Revenue Act (DORA).
The initial idea was to have a single consolidated capital grant for local government. However, this did not happen. Sector departments were unwilling to transfer their grants to another department
to administer them. The MIG was designed to support the multi-year budget system (MTREF) contemplated by SANT at that stage.
DBSA Guidelines for Infrastructure Investment Planning, 2000
These were simple guidelines with a spreadsheet model developed by Burgert Gildenhuys for the DBSA. However, there was a direct shift from dedicated planning for capital expenditure after introducing the new municipal system.
The
introduction of municipal legislation
The transformation of municipalities was completed by introducing a range of legislative matters that affected municipal government. The basis for this legislation was the Development Facilitation Act of 1995 (Act 1526 of 1995) and the Local Government Transition Act of 1995 (Act 260 of 1995).
The Development Facilitation Act (DFA) was significant since it required the formulation of Land Development Objectives (LDOs) for the transitional structures. Moreover, the DFA was the precursor to our SPLUMA, which only arrived in 2013.
The policy initiatives since the missions of the World Bank, the De Loor Task Group, and RDP were premised on improving the housing situation in South Africa. One
may include infrastructure investment planning in this group as well. The DFA was conceptualised to drive land release and housing provision. This is also why the Housing Act 1997 (Act 107 of 1998) was released even before the Municipal Structures Act 1998.
However, it is worth reading Chapter IV of the DFA. It provided a concise and focused exposition of what one finds challenging to achieve through SPLUMA.
The most important legislation introduced after the Demarcation Act of 1998 are:
- The Environmental Management Act of 1998 (Act 107 of 1998)
- The Municipal Structures Act of 1998 (Act 117 of 1998)
- The Municipal Systems Act of 2000 (Act 32 of 2000)
- The Municipal Finance Management Act of 2003 (Act 56 of 2003)
- The Property Rates Act of 2004 (Act 6 of 2004)
There was no landuse related legislation in this package of legislative interventions. Only a decade later, in 2011, the Constitutional Court declared the Development Facilitation Act unconstitutional and gave the government until June 2012 to rectify the problems it had identified when the Spatial Planning and Land Use Management Bill was published. It was legislated in 2013. (See below.)
Planning and Performance Management Regulations, 2001
The regulation in Section 4 states that a CIF must be prepared as part of the SDF within the framework of the IDP. The concept of infrastructure investment frameworks was well established and used at this stage. Notably, these principles were derived from the DFA 1995, which was repealed with the promulgation of SPLUMA in 2013.
Free Basic Services, July 2001
This policy seriously impacted municipal finances and the infrastructure delivery environment and practically nullified all success up to that point with cost recovery and payment for services. Burgert Gildenhuys drafted the first national free basic service policy guidelines.
2003 AND BEYOND: THE IMPLEMENTATION PHASE
In the period that followed, the brief but very intense adoption of municipal legislation introduced a period of developing plans,
Examples of municipal documents and reports produced by BCGA
guidelines and various tools to assist in achieving the objectives of the legislation.
The following list highlights a few of the more critical plans, policies and guidelines:
SANT Service Delivery and Budget Implementation Plan (SDBIP) 2005: Circular 13 of the MFMA introduced the SDBIP. Technically, it was yet another effort to expedite service delivery budget expenditure. Again, the SDBIP leveraging from the IDP is similar to that of the CIF.
COGTA Guidelines for Asset Management, 2007: These guidelines introduced the Comprehensive Municipal Infrastructure Plan (CMIP), contradicting or confusing many principles embedded in the MIIF.
Sector Master Planning was a standard practice in engineering, and it continued. The exception was water master plans (Water Services Act 1997). Solid waste, electricity, and transport got their legal mandates from 2007 to 2009.
DALRRD SPLUMA 2013: Notwithstanding the existence of municipal infrastructure investment frameworks, SPLUMA, in Section 21(d) of the Act, introduced the concept of a CEF. The Act states that “…changes at a more fundamental level are needed to ensure that sectoral programmes take into account municipal spatial planning, which also means that greater emphasis should be placed on the quality of municipal
spatial plans. Linkages are urgently needed between the local plans (e.g. SDFs and IDPs), the capital investment framework and the land-use management framework.”
SANT Built Environment Performance Plan (BEP), 2015: SANT issued guidelines that applied to similar elements in the CEF but to metropolitan municipalities. The CEF guidelines initially targeted intermediate cities.
COGTA IUDF, 2016: The IUDF required changes at a more fundamental level to ensure that sectoral programmes consider municipal spatial planning, which also means that greater emphasis should be placed on the quality of municipal spatial plans.
SANT Cities Infrastructure Delivery and Management System (CIDMS), 2018: Various guidelines and toolkits with an asset management focus.
COGTA CEF Guidelines 2017 and updates 2021: The first CEF guidelines were issued in 2017. Burgert Gildenhuys gave substantial inputs. In addition, the author was a specialist sub-consultant who compiled about 33 CEFs and revised seven CEFs that had been done previously.
Some conclusions
The outstanding feature of these interventions is that there are many similarities and often cross-purposes that
may lead to duplications, misinterpretations, and inefficiencies. Why this plethora of policies and guidelines was developed is not always clear. There may be three reasons: Fristly, the objectives set in enabling legislation are high-level and often strategic. These objectives are often challenging to quantify, and non-achievement or perception of non-achievement triggers an intervention in the form of guidelines or some regulatory interventions.
Secondly, there is a strong drive from the provincial governments and national government departments to ensure or enforce compliance and conformity in outcomes. The result is increased regulatory control, the enforcement of uniform policies or the adoption of guidelines to ensure a consistent approach across often diverse circumstances.
Thirdly, the institutional capacity and the capability of officials and professionals dealing with many development issues in municipalities may not be at the required level. Issuing guidelines and toolkits may be an attempt to overcome these shortcomings. However, lacking skills and experience cannot be remedied through a recipe or a “paint by numbers” approach.
* Pr. Pln, MIAM (London), ILGM, B(TRP), BAdmin (Municipal Administration)
Concor was honoured by the Master Builders Association (MBA) North, winning in the regional category for projects under R15 million, for the construction of the new drop-off and pick-up facility at Menlyn Park Shopping Centre, along with the reconfiguration of an underground parking area into a taxi holding facility
MENLYN TAXI INTEGRATION PROJECT
Concor's fast track implementation underscored by safety award
Concor once again showcased its remarkable ability to execute complex, fast track projects with exceptional efficiency and safety during the construction of the new drop-off and pick-up facility, along with the reconfiguration of an underground parking area into a taxi holding facility at Menlyn Park Shopping Centre.
The company was honoured by the Master Builders Association (MBA) North, winning in the regional category for projects under R15 million. The MBA North regional safety competition saw 67 entries, including 60 principal contractors and 7 sub-contractors.
Menlyn Park Shopping Centre, one of South Africa's largest mega shopping centres, boasts a diverse array of over 500 shops, restaurants and entertainment facilities. The centre attracts a vast number of shoppers and visitors each month, necessitating a significant workforce to support its operations. While some commuters use personal vehicles, the majority rely on minibus taxis for transportation. To streamline this process and enhance the commuter experience, a publicprivate partnership was established for the construction of the taxi holding facility.
Concor Contract Manager, Martin Muller, explains that the company is known for
managing high-pressure construction programmes effectively, and applied attention to planning underpinned by effective programme management to ensure every phase of the project dovetailed seamlessly.
The project, initiated in February 2024 and completed by April 2024, was delivered on time and within budget, ready for the official opening by the Tshwane mayor.
Despite the tight timeline, the project was executed without any incidents, a testament to the rigorous safety protocols implemented.
The construction site, active within a live retail environment, required meticulous traffic management and pedestrian safety measures.
A full-time safety officer ensured compliance with all safety procedures, leading to a Five Star safety rating from the MBA North.
Another of Concor’s significant strengths lies in involving local SMMEs and individuals from the communities where it operates. On
this project, Concor engaged with community representatives to source, vet and employ SMME subcontractors, offering opportunities in trades such as brickwork, plasterwork, painting, paving and plumbing.
Muller says that while the contract period was too short for a formal skills development programme, local labourers were given the chance to work on the project, gaining valuable experience and mentorship.
Optimum facility location
The drop-off and pick-up facility is strategically located on the northern side of the centre, accessible from Atterbury Road. This facility enhances the movement of taxis, allowing for safe drop-off and pick-up of passengers. Commuters benefit from a designated pedestrian walkway leading directly into the mall, which is both safer and sheltered from the elements.
The facility can accommodate around 40 taxis at any given time within its spacious footprint. The construction involved extensive groundwork, soil stabilisation, and paving to ensure durability under high traffic volumes. Security measures include fencing around the area and structural steel canopies with reinforced concrete foundations. The pedestrian walkways were also designed with aesthetic landscaping.
In addition to the primary logistical infrastructure, provisions were made for registered informal traders to set up kiosks,
The taxi holding facility was integrated within the centre’s existing parking structure. It includes 165 parking bays, with 135 for standard minibus taxis and the remainder for larger long-distance minibuses
The taxi holding facility features utility areas, including a rest area with a kitchen, ablution facilities catering to disabled individuals and a wash bay. Sustainable design elements were also incorporated such as sensor-based lighting and water-efficient fixtures to reduce resource consumption
offering food and other goods in a secure and sanitary environment with shelter from inclement weather. Nearby, 24/7 accessible ablution facilities ensure safe and hygienic conditions for commuters and taxi operators.
Muller explains that previously, taxis lined Lois Avenue on the eastern side of Menlyn Park Shopping Centre, creating hazardous conditions for both commuters and other vehicles. “The new facility alleviates these issues by providing a controlled environment for taxi operations and commuter safety.”
Parking integration and access
The taxi holding facility was integrated within the centre’s existing parking structure. It includes 165 parking bays, with 135 for standard minibus taxis and the remainder for larger long-distance minibuses. Access is controlled via license plate recognition, with separate entrances for short-distance and long-distance operators. The area is secured with fencing, and the parking layout was upgraded with energyefficient LED lighting and clear demarcation of bays.
The holding facility also features utility areas, including a rest area with a kitchen, ablution facilities catering to disabled individuals and a wash bay. With a focus on the environment, sustainable design elements were incorporated such as sensor-based lighting and water-efficient fixtures to reduce resource consumption. The dedicated wash bay encourages water conservation among taxi operators while providing a suitable vehicle cleaning area.
As with all its contracts, Concor’s commitment to community upliftment extended beyond the project site with the company identifying needs within local communities. In this instance the company donated building materials to a nearby school for an upgrade project, collaborating with the professional team to support local education infrastructure.
“Concor’s successful execution of the Menlyn Taxi Integration Project underscores our capability in handling complex fast track projects with precision and excellence,” adds Muller.
“This project not only improved the commuter experience at Menlyn Park Shopping Centre but also, once again, showcased our dedication to quality, safety, and community engagement,” Muller concludes.
MAINLINE CIVIL ENGINEERING LEADS SA'S LARGEST EVER PIPELINE REHABILITATION PROJECT
Mainline Civil Engineering Contractors (Mainline) has successfully spearheaded the country's largest sewer rehabilitation project, transforming part of Cape Town's critical underground infrastructure through its cutting-edge technology and expertise.
With decades of national and international experience, Mainline stands at the forefront of pipeline construction and rehabilitation in South Africa. Their solutions-focused expertise, state-of-theart equipment and comprehensive trenchless methodologies ensured the company’s success in this unprecedented infrastructure challenge.
Since 2020, Mainline has been awarded numerous works packages on the R796 million Cape Flats Bulk Sewer Rehabilitation Project by the City of Cape Town. On completion of the various works packages awarded to date, Mainline will have fully rehabilitated over 10 km of bulk sewer pipeline utilising a spirally wound pipe (SWP) system. To date, Mainline has successfully cleaned, profiled and CCTV-inspected over 16 km of pipeline, and rehabilitated over 70 manholes, along with the bulk sewer rehabilitation.
Overcoming challenges of infrastructure in crisis
Constructed in the 1960s, the Cape Flats twin bulk sewers have been the backbone of this area of Cape Town's sanitation infrastructure for over half a century. The system, comprising two reinforced concrete sewers ranging from 1 000 mm to 1 800 mm in diameter, serves an extensive 8 000 hectare area encompassing 300 000 households and approximately 880 000 citizens. Decades of use led to severe structural deterioration, significant
sediment build-up and groundwater infiltration, threatening the system's functionality.
The contract anticipated using the “twin” sewer line to accommodate the flow from the adjacent pipeline under rehabilitation. However, due to the significant build-up of sediment, debris and blockages, this proved to be very challenging. The contract also originally envisaged that pipelines could be cleaned by high pressure jet cleaning. However, given the state of the pipeline, it was impossible to remove the blockages without manentry and vacuum excavation of the consolidated sediment in the pipeline. This hazardous confined-space work required a brave team to toil underground for months in order to provide a clean pipeline for assessment and rehabilitation.
Despite these challenges Mainline was able to ensure the bulk sewer flow remained functional and contained throughout the rehabilitation process, pumping up to 84 000 litres per hour round the clock.
A positive and award-winning outcome
Between 2020 and 2024, the various City of Cape Town works packages created over 1 million man-days of job opportunities for local skilled and unskilled labour.
“The rehabilitation of the Cape Flats Bulk Sewer has had a huge impact on the surrounding communities, not only through the employment opportunities created, but with the complete replacement of severely deteriorated bulk sewer pipelines – prior to the rehabilitation, blockages
and dangerous overflows were a common occurrence,” says Jared Smith, Mainline Contracts Manager for the project.
Additionally, before the rehabilitation of the bulk sewer, sewer lines were blocked up to 80% of their capacity; now the lines will be able to run at full capacity with a greatly reduced risk of blockages for decades to come.
The largest rehabilitation project in South Africa’s history, the Cape Flats Bulk Sewer Rehabilitation is one of the city’s flagship projects and plays an integral part in the Mayor’s rehabilitation plan. In a show of maintenance commitment, the city invested in 23 jetting trucks to service and maintain sewer infrastructures in Cape Town.
As a result of the many pioneering methodologies, technologies and materials used in these endeavours, Mainline was also awarded the prestigious Joop van Wamelen Award of Excellence by the Southern African Society for Trenchless Technology (SASTT).
“Mainline is a dominant player in South African pipeline rehabilitation and the successful completion of these impressive SWP projects within budget and on time amplifies our capabilities and commitment to remaining a pioneering service provider,” Smith concludes.
Mainline is a specialist civil engineering contractor in the field of pipeline construction, the trenchless installation of underground pipelines and utilities, and trenchless pipeline rehabilitation and tunnelling in both the public and private sectors.
(Photo credit:
City of Cape Town)
RENEWABLE POWER INITIATIVE KEY TO OMMP IMPLEMENTATION
Sustainable Power Solutions (SPS) has been selected as the preferred bidder for a significant contract by the Lebalelo Water User Association (LWUA), soon to be known as Badirammogo Water User Association, to provide a Renewable Energy Solution (RES).
SPS’ solar photovoltaic (PV) and Battery Energy Storage System (BESS) solution will provide power to key infrastructure for the first stage of a vital water infrastructure development initiative in Limpopo, known as the Olifants Management Model Programme (OMMP).
The OMMP is a public-private collaboration between institutional members (government) and commercial members (the private sector, including mining companies and industrial users), and is being implemented by LWUA.
Infrastructure footprint
The OMMP involves constructing 200 km of bulk raw water pipelines and 675 km of potable water pipelines, along with several pump stations, reservoirs and water treatment works. Rolled out in phases, the programme fast-tracks bulk raw and potable water supply infrastructure for communities and commercial users in Sekhukhune and Mogalakwena, optimises the existing infrastructure and water supply of the De Hoop and Flag Boshielo Dams in the Middle Olifants catchment, and enhances water supply to Polokwane Local Municipality, which faces a 30 Mℓ/day water shortage.
As part of the contract, SPS will employ leadingedge solar and battery technologies to power key
infrastructure that forms part of Phase 2B and 2B+ of the OMMP, for a duration of 25 years.
Phase 2B and 2B+ of the OMMP includes a new pipeline that will transport bulk raw water from the Flag Boshielo Dam to reservoirs across the Northern Limb of the Bushveld Igneous Complex. From there, 40% of the water will supply mines, and 60% will be treated at water treatment plants in Mokopane and Sekuruwe, providing potable water to 140 000 community members and addressing Mokopane’s water shortfall.
Solar capacity
The solar energy capacity will start at 16 MWp for phase one, increasing over two further phases over the next 10 years to 23 MWp in the final phase. The BESS, with a capacity of 13,3 MWh, will ensure a reliable and sustainable power supply for the three pump stations under construction, each to be equipped with two 3,5 MW pumps. The RES will provide all operational and auxiliary power to the three pump stations, as their current locations prevent connection to the utility grid.
SPS’ contract is an integral part of the larger OMMP, which is optimising and accelerating the completion of the government-conceived Olifants River Water Resources Development
Project (ORWRDP) and expanding its scope to include potable water infrastructure.
“SPS emerged as the successful bidder in a competitive tender process, showcasing their extensive expertise, flexibility and ability to tailor funding solutions. Their innovative approach to integrating renewable technologies and sustainable practices positions them uniquely to meet the energy needs of the Association’s expansion into the Northern Limb through the OMMP,” explains Bertus Bierman, CEO of Lebalelo Water User Association.
The RES will also have a profound environmental impact, reducing over 13 million kilogrammes of carbon emissions annually by eliminating the need for diesel generators.
Social and economic development
In accordance with tender requirements, 1% of the project value will be allocated to Socio-Economic Development (SED) initiatives. This will ensure that local communities benefit directly from the investment through potable water, enterprise development, education and connectivity. A key SED initiative that forms part of the OMMP is the School Upgrade Programme, which provides essential infrastructure to schools across Limpopo to foster educational advancement.
Beyond water security, the programme will fuel industrial development and regional growth in Sekhukhune, Mogalakwena and Polokwane. The impact is far reaching as the full OMMP is expected to create around 42 000 jobs (direct, indirect and induced), thus bolstering the local economy.
Demolition of the original Refinery Interchange overpass bridge
REFINERY ROAD INTERCHANGE PART OF A BROADER CAPE TOWN FREEWAY INTEGRATOR INITIATIVE
As cities evolve, so to do their transportation networks to cater for current and future spatial development planning. A prime example is SMEC’s contribution to the evolution of Cape Town’s north and south development corridor – the N1 and N7 routes – which prioritise free flowing urban travel, unlock opportunity through improved access along the corridors, coupled with longer-term overall integration of freight and public transport and commuter rail interconnectivity.
As a key enabler, SMEC is one of the appointed consulting engineering firms retained by the Western Cape Government’s Department of Infrastructure (DoI) – the latter being the implementation agent – to roll out key projects in phased packages. A landmark development was
SMEC’s design and construction supervision of the Refinery Road Interchange upgrade on the N7, forming part of the DoI’s current and future Cape Town Freeway Integrator initiative.
“In the pipeline for future integrated works is the upgraded Wingfield Interchange on the N1 and N7 – also part of SMEC’s scope –
which is currently in the preliminary design stage. The latter forms a central component of the DoI’s programme to provide improved interconnectivity between various suburbs that enable cross access north to south, east to west along socioeconomic corridors,” explains Jurgen Oosthuyse, SMEC’s Regional Manager, Western Cape.
Key planned additions to the Wingfield Interchange include revamps to the Frans Conradie Drive, Prestige Drive and Sable Road interchanges (the latter now in the detailed design phase); two new primary arterial roads that will incorporate space for non-motorised transport; plus, Bus Rapid Transport (BRT) lanes and new BRT stations.
Ultimately, and as part of the Cape Town Freeway Integrator initiative, works interventions will include:
• Ten interchanges (four new and six upgrades).
• 33 bridges (21 of which will be new, in some instances to replace those that have exceeded their design life).
• Associated ancillary structures, such as retaining walls, culverts, sign gantries and impact barriers.
• The upgrading and relocation of utilities infrastructure, including stormwater, electricity, and telecoms to make provision
A north elevation perspective of the completed B6068 and B6089 Refinery Interchange overpass bridges
for road works. In sections, overhead high voltage lines will need to be transferred to underground installations.
• Allowance for new public transport infrastructure networks for MyCiTi bus routes.
1 West elevation of pour strip showing cast-in splice bars projecting from the deck edges
2 A south elevation perspective of the widened B6056 road-over-rail bridge
3 Aerial image showing completed upgrades to the Refinery roadover-rail bridge 1 2 3
widened on the southern end with mechanically stabilised embankment walls, and received structural topping to correct the cross-fall.
A flexible solution for the Refinery Road Interchange
“For general commuters and commercial enterprises, upgrading the Refinery Road Interchange [at the juncture of Trunk Road 11 Section 1 (N7) and Plattekloof Road (M14)] was a pressing priority due to severe congestion,” explains Cobus Hendriksz, Function General Manager: Roads & Highways at SMEC South Africa. “This was the first major interchange package awarded.”
In response, the scope of works entailed the construction of new overpass dual carriageway bridges over the TR11/1(N7) to accommodate
a new westbound carriageway (WBCW) of the Plattekloof Road (M14), namely the B6068 and B6089 (completed in December 2022 and December 2023, respectively). On the critical path was the future demolition of the existing B4247 two-way lane structure once the first new interchange bridge, the B6068, was constructed.
Road-over-rail bridge
An existing road-over-rail bridge (B6056), built in 1969 – and measuring 15,2 in length – was also
The Transnet-owned rail reserve beneath the B6056 runs parallel to the N7 (TR11/1) and consists of two tracks and an unpaved service road in front of the east abutment. The western track terminates at the nearby Astron Refinery, while the eastern one serves as the main freight route between Cape Town and Atlantis. A future third track is planned in front of the east abutment and will serve as a commuter route between these same destinations. At the time of construction, the rail reserve was not operational.
Clearance issues remedied
Bridge No. B6068 was constructed immediately south of B4247. Following its completion, bidirectional traffic flow on Plattekloof Road was transferred onto it in early December 2022 and the
A night-time perspective of the completed Refinery Road Interchange project
existing B4247 was subsequently demolished in the same month.
“The reason for its demise – aside from its restrictive lane configuration – was that it had insufficient vertical clearance, making it unsafe for heavy vehicles carrying high or abnormal loads, which had resulted in a number of overhead bridge collisions,” says Hendriksz.
Current WCG standards specify a minimum allowable vertical clearance of 5,0 m for existing bridges (after future overlays) and 5,2 m for new bridges. However, B4247 was originally designed for a vertical clearance of 4,9 m, which further reduced over its lifetime due to resurfacing of the underlying road.
B4247 was a four-span simply supported 59,3 m long structure with a typical span length of 18,3 m. The bridge had a beam-and-slab type design, which comprised seven precast prestressed beams in the end spans and nine precast prestressed beams in the main spans. The deck was supported on reinforced concrete abutments and piers, all founded on spread footings.
In contrast, the new bridges have 98,4 m long, cast in-situ, six-span, twin-spine continuous prestressed concrete decks. The decks are monolithic with the three central piers and are supported on pot bearings at the outer two piers and abutments. The decks consist of 800 mm deep precast, pretensioned M-beams and a 200 mm thick cast in-situ deck slab.
Cast in-situ pour strip
The use of a cast in-situ pour strip allowed the bridge decks to be successfully joined together, while minimising differential shrinkage between them. Mechanical couplers were originally detailed to connect the pour strip’s transverse
reinforcement to that of the decks. However, a request was approved to use splice bars cast into the deck edges in place of the couplers on the basis that this option would be more affordable and easier to install. This however required revision of the pour strip’s original reinforcement details. Additionally, the splice bars were installed at the same crossfall of each deck, requiring them to be individually bent downwards to provide sufficient cover to the top of the pour strip.
To limit differential creep and shrinkage movement between the decks, a minimum waiting period of four months was specified between final stressing of the second deck and casting the pour strip. An additional requirement was that no traffic could travel over either deck during casting – with the exception of readymix trucks – for a maximum of three days afterwards.
The formwork consisted of beams laced transversely between the deck edges from which panels were suspended and tied flush with the adjacent soffits. This layout eliminated the need for drilling or forming tie-holes through the adjacent deck edges. However, the combination of tie rods passing regularly through the pour strip, and small gaps provided between the beams and the pour strip’s top surface, made proper curing particularly challenging. This resulted in the development of extensive, narrow surface cracks, which were later sealed using an epoxy grout.
Another design success was the inclusion of integral piers, which eliminated the need for bearings, thereby further reducing maintenance requirements. This approach did however create a stiffer system whose design required heavier reinforcement in both the deck and the substructure.
A view of the completed Plattekloof Road WBCW section
Geotechnical
The bridges are founded throughout on Ø610 mm driven cast in-situ (DCIS) piles. This method conventionally involves driving a temporary casing into the ground before lowering reinforcement into it and concreting the pile. The bridge foundation design required a minimum pile depth of 7,0 m. However, due to the frictional resistance offered by the sandy soil, driving the temporary casing to this depth was not feasible. The piling technique was consequently adapted to include pre-drilling of the pile shafts before lowering in the temporary casing. However, the relatively shallow groundwater on site made this operation challenging as wet soil would often cause the pre-drilled shafts to collapse before/ during installation of the casing. Raked piles at the abutments were especially susceptible to this issue. Careful monitoring of the piling operation was therefore required to identify and record each pile shaft collapse. Of the 169 piles installed, 27 were affected by collapses, resulting in a combined delay of seven working days.
Shaft collapses were usually overcome by either redrilling the shaft or pre-forming a “plug” of 20 mm stone at the base of the casing and driving it through the collapsed material. However, these solutions were rendered ineffective by a shallow water table at the eastern supports of B6089. Instead, dewatering around Pier 5 and Abutment 2 was undertaken here by installing well points and employing a continuous pumping system to remove groundwater from the work area.
In addition, a polymer slurry was pumped into the pre-drilled pile shafts at these positions to temporarily support their walls before installing the casings. During concreting, the slurry would be displaced from the shafts and retrieved for filtering and reuse. The combination of these solutions effectively mitigated any further issues at this position.
Conclusion
“The completion of the Refinery Interchange project is a landmark development, with progressive interchange revamps designed to align with the DoI’s expanding collector distributor road network to facilitate residential and commercial spatial expansion,” adds Oosthuyse.
“The city’s macro transportation model also includes a fully integrated commuter and freight network in the future. Overall, it’s a massive infrastructure and planning undertaking, which positions Cape Town for major future growth,” Oosthuyse concludes.
Routine and periodic maintenance of rural road infrastructure requires more attention
ith South Africa’s road network playing a pivotal role in the country’s economic recovery and growth, proper planning and scheduled road maintenance in rural areas also needs to be prioritised, says Ntsika Mhlanga, Route Manager at Zimile Consulting Engineers.
The Department of Public Works’ National Infrastructure Plan 2050 alludes to this by highlighting that more than 80% of the country’s provincial roads are gravel, but with only 1% being re-gravelled every year.
“With regard to the growing maintenance backlog, in our experience, the best way to reduce this is through collaboration with provincial governments and local municipalities to plan and schedule these routine activities,” he explains.
More than 80% of the country’s provincial roads are gravel
RURAL ROADS NEED MORE ATTENTION
Measuring and monitoring
He proposes a system where data for each road is captured and tracked per maintenance period, while maintenance activities are scheduled based on the needs of each road to ensure design and construction lifespans are achieved.
“The system should be able to identify fluctuations in road usage and assign road maintenance schedules aligned to a budget and a plan. We can also assist provincial departments in planning and road maintenance schedules,” he continues.
“As responsible consulting engineers, producing quality upgrades for our clients, and with detailed planning, we are also able to incorporate appropriate designs, such
as safety barriers and drainage systems,”
Mhlanga expands. He cites a recent project where Zimile conducted routine maintenance on a road in Piet Retief that was deteriorating rapidly as a result of use and heavy rains.
Mhlanga argues that addressing the challenges of rural road infrastructure is not just about improving transportation, but also about enhancing economic opportunities.
“The current state of many rural roads hinders access to markets, employment opportunities, and basic services, effectively isolating these communities and limiting their income potential. We should, therefore, continue to prioritise the development and maintenance of rural roads,” Mhlanga concludes.
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REDESIGNING A RAIL CROSSING TO FREE UP ROAD TRAFFIC
In the heart of Melbourne’s southeastern region, the suburb of Narre Warren used to experience significant traffic congestion at Webb Street – where it intersected with a rail level crossing – requiring the need for an urgent and innovative engineered solution.
Historically, over 13 000 vehicles passed through the intersection every day and the boom gates were down for up to 33% of the morning peak travel time. Recognising the urgency to address this issue, the Victoria State Government responded with the initiation of the Webb Street Level Crossing Removal Project to alleviate bottlenecks while enhancing the overall transportation system's safety and efficiency by separating vehicles and trains.
To achieve this, a 1 km section of the rail line needed to be elevated, with the crossing over Cranbourne Road requiring two massive steel half-through bridges weighing 680 tonnes each. However, constructing the bridge using traditional stick-built methods would have required extensive road closures, causing major disruptions to Cranbourne Road, a key arterial in the suburb. The challenge was to work within a built-up urban area with limited space while keeping the arterial road operational for as long as possible.
ABC technique
Mammoet, renowned for its engineering and operational expertise, was tasked by McConnell Dowell – the project’s principal contractor – with devising a solution that would mitigate the impact on the public.
Drawing on Mammoet’s extensive experience with bridge projects globally, the team proposed an Accelerated Bridge Construction (ABC) approach. This method involved fabricating the bridge offsite, in a convenient location near its
For the Webb Street Level Crossing Removal Project, a 1 km section of the rail line needed to be elevated, with the crossing over Cranbourne Road requiring two massive steel half-through bridges, each weighing 680 tonnes
installation point, then transporting it to its final position and installing it in a few days or hours. This minimised the project’s footprint and avoided extensive road closures.
Utilising self-propelled modular transporters (SPMTs) in combination with the JS500 jacking system, Mammoet executed the operation with precision. First, the SPMTs raised the bridge sections from 1,5 m to 4,2 m high to prepare for the main jacking operation. Next, with SPMTs reconfigured and JS500 jacking units secured, the team jacked up the bridge to a transport height of 9 m, ensuring clearance over street furniture and other obstacles.
Transporting the 50 m long sections through Narre Warren's congested streets (with houses, trees and power lines) required thorough planning. The team carefully navigated the route, and once at the installation location, the bridge sections were gently jacked down onto their foundations. The selected installation methodology not only minimised traffic congestion, but also mitigated safety risks typical in traditional construction methods. Thanks to this, the new rail bridge now rises over Narre Warren, with cars, pedestrians, and cyclists travelling underneath.
This level crossing was the 14th removed by the Victoria State Government on the Pakenham Line, with more work underway to make the line boom gate free by 2025.
Transporting one of the 680 tonne bridge sections to the construction site
Utilising self-propelled modular transporters (SPMTs) in combination with the JS500 jacking system, Mammoet executed the bridge installation sequences with precision
RIVERLANDS DEVELOPMENT INVESTS IN CITY INFRASTRUCTURE
The Riverlands Development in Observatory, Cape Town, will soon be able to hand over significant services upgrades to the City of Cape Town and the Western Cape Provincial Government.
These upgrades include the new roadway and bridge linking Observatory with Ndabeni, the upgrade to Berkley Road, external bulk works surrounding the development, the Liesbeek riverine rehabilitation, upgraded sewerage works, and other external services upgrades. This R120 million project is part of the developer Zenprop’s commitment to upgrade public infrastructure surrounding the Riverlands commercial, retail and residential precinct.
Significantly, the new road and bridge spanning the Black River will soon connect Liesbeek Parkway with Berkley Road and the M5, offering Cape Town a new way to connect the economic and industrial hubs from the city centre through Woodstock to Epping.
Speaking during a ribbon-cutting event, James Tannenberger of the Liesbeek Leisure Properties Trust said that the project will be a permanent and positive enhancement to the daily lives of those who live in Cape Town. “This project isn’t just about a road or a bridge – it’s about enhancing the quality of life for every Capetonian, creating opportunities for businesses to thrive, and laying a foundation for future growth,” he said.
Habitat preservation and stormwater management
The riverine rehabilitation has included removing the concrete bedding previously installed in a section of the Liesbeek River and returning the area to a more natural state. This section of the Liesbeek has now been replanted, and special care has been taken to create habitats for indigenous animal and birdlife.
By cleaning up pollution, improving water quality, and restoring natural habitats, Riverlands is not just helping the environment, but also creating the structures to make Cape Town’s waterways more resilient to extreme weather events. During the recent elevated rain levels in Cape Town, the newly rehabilitated riverine section did not flood.
Commercial operations
The Riverlands precinct will also soon be open to the public. Commercial tenants will start to occupy the precinct during October, and the retail section will open in November 2024. The latter will include blue chip anchor tenants such as Woolworths, Checkers, Clicks, Mr Price, Vida e Caffe, Cattle Barron, Nando’s Restaurant and a full range of smaller retailers.
The residential units at Riverlands have also proven popular owing to the central location of the development, with over 65% already pre-sold. Ultimately, Riverlands’ integration of commercial, retail and residential elements will create a vibrant and interconnected community where residents can live, work, and play within a single, safe precinct.
The teams involved in the development and construction of the public infrastructure surrounding the Riverlands Development in Observatory, Cape Town, celebrate the completion of the project, together with Cape Town Mayor Geordin Hill-Lewis and Deputy Mayor Eddie Andrews
AECOM SHOWCASES ITS DIGITAL DESIGN CAPABILITY ON MALMESBURY BYPASS
Globally trusted infrastructure consulting firm AECOM has used the latest digital tools to fast-track the final design of the new R45 link between the N7 and R46 at Malmesbury for the Department of Infrastructure in the Western Cape.
The advanced design process commenced in 2022. Our full suite of digital tools played a major role in getting the project up to speed,” explains Nabeel Omar, Technical Director: Highways and Transportation Lead, Western Cape.
AECOM deployed a full 3D model to optimise quantities and ensure accurate construction cost estimates, which has rolled over into the project management of the actual construction to ensure what was designed is built accordingly.
“The project has the hallmarks of any typical complex engineering project with various interfaces,” comments Danie du Plessis, Technical Director, Highway Geometry. Challenges included the topography, the relocation of fibre and telecoms lines, power transmission lines and pylons, plus the fact that the project crosses the major water source for the town of Malmesbury, which necessitated additional protection measures.
East-West link
A critical infrastructure project for the Western Cape, it forms part of a larger 170 km road network between the Port of Saldanha in the West and the N1 and N2 in the East. The so-called Malmesbury Bypass falls under the Strategic Integrated Project 5 of the National Infrastructure Plan 2050, the Saldanha-Northern Cape Development Corridor.
The Port of Saldanha was identified as a national growth point in terms of the
fast-tracked the final design of
government’s then adopted infrastructure plan. To support and initiate this growth, both national and provincial governments are making significant investments to expand the port and establish an Industrial Development Zone.
The East-West link has long been in the planning stages, with AECOM subsequently working on additional sections, reveals Omar. The N2 is the major route for freight transport between South Africa and Mozambique and the N7 to Namibia. “It is also crucial for the successful operation and capacity of provincial roads in general in the region, as previously freight traffic had to pass directly through Malmesbury, hence the need for the bypass,” says du Plessis.
The new Malmesbury Bypass, a 6.7 km greenfield link, consists of 2 x 3.7 m wide lanes and 2 x 2.4 m surfaced shoulders. It includes two road-over-road underpass bridges, a river bridge, a bridge spanning an environmentally sensitive wetland and an interchange bridge. Various stormwater structures are included given the recent flooding and to ensure resilient futureproof infrastructure, and an agricultural underpass for access for a landowner.
Community training and SMME development
The project is anticipated to generate about 45 000 worker person days and over 290 work opportunities. About 25% of the project budget is being allocated to local service providers, either in the designated area or the broader Western Cape, as well as 60 work packages for the upliftment and empowerment of local subcontractors. “There is a significant social investment
AECOM
the new R45 link between the N7 and R46 at Malmesbury in the Western Cape
Danie du Plessis, Technical Director, Highway Geometry, AECOM
Nabeel Omar, Technical Director: Highways and Transportation Lead, Western Cape, AECOM
in upskilling and training the local communities,” notes Omar.
This includes awarding works packages to up-and-coming local subcontractors and training being provided by the main contractor and the site team to assist these subcontractors to achieve their CIDB grading. AECOM has a
Community Liaison Officer on-site while the municipality maintains a database of eligible subcontractors.
The training ranges from financial management to scarce skills like carpentry or scaffolding erection to ensure future work opportunities. “It is sustainable, and not just for the duration of the project. It
The Malmesbury Bypass project has been a major testament to AECOM’s digital capabilities
must generate meaningful employment in the long term,” adds Omar.
Health and safety are key, with audits being conducted regularly and AECOM’s Lifeguard and IndustrySafe safety management software being used to track any issues, which are resolved within 20 to 30 minutes.
“We also have professional engineers on standby to address any queries quickly and efficiently. To date, there have been no major issues or incidents on what is essentially quite a fast-track project,” says du Plessis.
The timeline to date has been preliminary, with detail design commencing in January 2022 and a hard deadline for the latter by end May 2022. AECOM achieved this successfully, with the project going out to tender in October 2022. H&I Construction was appointed for the construction works, starting in May 2023, which are expected to be completed by November 2026.
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Concrete block paving restores a vital rural route
Situated within the Greater Letaba Local Municipality in Limpopo, the maintenance of road D3179 from Medingeng to Malematsa has reconnected rural communities.
PROJECT DETAILS
Project Name: RAL/T1029/2021:
Rehabilitation of road D3179 from Medingeng to Malematsa
Client: Road Agency Limpopo (RAL)
Consulting Engineer: Makhaotse, Narasimulu and Associates (MNA)
Contractor: Masheleni Trading & Projects
Project Completion: 24th July 2024
Budget: R40 million
A section of the D3179 prior to reinstating with a concrete block paved surface
Prior to the project, the road’s deteriorated condition made vehicle traversal impossible in certain sections between Ga-Kgapane and Medingeng due to extensive erosion. The community faced severe challenges in terms of access to work, markets, healthcare centres, and schools, with growing frustration often leading to service delivery protests.
In response, Road Agency Limpopo implemented an urgent remediation solution, which ran over a period of approximately 15 months. Completed in July 2024, design and construction supervision was carried out by
Makhaotse, Narasimulu and Associates (MNA), with the works executed by main contractor, Masheleni Trading & Projects, at a contract value of R40 million.
A distinctive feature of this new 6 m wide and 4,5 km long Class 4 road – which winds through hilltop settlements – is that it was originally constructed in three sections with a 60 mm thick concrete block paved surface. This has now been restored and extended to replace heavily degraded asphalt sections, along with a series of allied engineered interventions.
Sustainable and durable
Some 70% of the block paving is new, with the balance reused in the road improvement works, thereby promoting sustainable construction practices. Designed to accommodate buses and other heavy vehicles, an added advantage is improved stability and therefore safety for vehicles navigating steep sections.
“Although concrete block paving might be seen as a more expensive option compared to an asphalt overlay, its long-term durability and lower maintenance justified the cost due to the unique circumstances and topography. Additionally, opting for concrete block paving enabled the extensive use of labour-based construction, enabling job creation and skills development,” explains Edwin Zumba, MNA’s Resident Engineer for the project.
MNA’s assessment of the existing 5 m wide asphalt sections confirmed that the road surfacing and substructure could not be suitably improved with periodic maintenance or remedial interventions. This was due to severe failures resulting from surface deterioration, water
A Google Earth perspective showing the 4,5 km maintenance section highlighted in yellow
ingress, as well as a structurally inadequate existing pavement (as noted in the geotechnical investigation of the in-situ layer works).
This therefore warranted the need for intensive rehabilitation and maintenance. Conventional patching and pothole repairs would not have solved the underlying pavement issues or offered a longer-term solution.
In turn, their analysis of the existing concrete block paved sections showed that they had generally stood the test of time in terms of surfacing condition. However, these pavers had been founded on an unsuitable subgrade material of G9/G10 quality. It was therefore recommended that the existing in-situ material be rehabilitated and replaced with G5 material for the subbase, followed by the reinstallation of the concrete pavers (either new or existing ones). The same methodology was applied for the new sections.
For uniformity the 5 m wide asphalt road sections were re-constructed to 6 m, and here the layer works were also fully rehabilitated to accommodate the additional 1 m width.
Erosion and flood control
To prevent future erosion and landslides – a common issue in the area – slope stabilisation measures were incorporated, safeguarding the roadbed and surrounding terrain in what can be a seasonally heavy rainfall region, with major run-offs.
Adequate drainage systems, including culverts, dish crossings, and stormwater management infrastructure, now mitigate flooding risks. The road's grading and surface treatments have also been optimised for proper drainage and traction.
Preparing the subbase
During construction, the topography of the area and space limitations restricted the full width construction of the road as there was limited space available to accommodate safe deviation routes. Therefore, the road was constructed in half widths where possible. However, during subbase construction the road had to be constructed in full width due to the complication of stabilisation in half widths.
An additional complication in these sections was accommodating traffic while allowing sufficient curing time on the subbase. The problem was overcome by using a sacrificial layer on top of the stabilised layer, which allowed vehicular movement without compromising the quality of the completed layer.
Community engagement and downstream benefits
To ensure the project's success and sustainability, the community was consulted well before project execution. Their input was crucial
in the planning stages, allowing the project to be tailored to their current and future needs wherever practical. Additionally, the community was actively involved in the construction phases.
The 22 local general labourers employed during the project benefitted from a comprehensive and structured training programme, with these newly acquired skills enhancing their future job prospects.
In addition to general labour compensation – amounting to over R1,5 million – more than R3,1 million was also spent on utilising local SMMEs. Sixteen local businesses benefitted as sub-contractors and suppliers over the project duration. Furthermore, materials were sourced locally whenever possible, supporting the regional economy.
Civil engineering in practice
“This project has significantly increased the visibility and value of civil engineering in the region, showcasing how innovative design and construction techniques can be adapted to meet fit-for-purpose requirements,” adds Zumba.
“More importantly though is the transformative effect on residents' lives by improving accessibility, enhancing safety, and fostering socio-economic development,” Zumba concludes.
An existing paved section, which has stood the test of time well
Kerb installations being installed prior to commencing surfacing with concrete block paving
A newly completed section of the D3179
The 22 local general labourers employed during the project benefitted from a comprehensive and structured training programme, which included concrete block paving techniques
The asphalt sections became impassable and led to numerous accidents
A failed asphalt section
How municipal engineers will deliver the 2026 swing vote
Deon van Zyl is the chairperson of the non-profit Western Cape Property Development Forum (WCPDF).
The organisation will further be exploring the topic of “Recalibrating the development conversation” at its 2025 Annual Conference, being held between the 4th and 5th June at the Cape Town International Convention Centre
The two-year track record of Cape Town
Mayor Geordin Hill-Lewis is a key example of what is possible when the political executive applies its mind. Cape Town’s spending on infrastructure is occurring at a level not seen since democratisation. In turn, the city is pushing hard to ensure all its engineers are professionally registered.
What drives this agenda is that, within a generation, Cape Town will reach a population of 10 million. We also see a more urbanised electorate becoming increasingly educated, with higher aspirations for decent living standards. Voters are starting to shrug off the mantel of being voter fodder.
Back in 2021, the Western Cape Property Development Forum (WCPDF) dared to call for the return of the municipal engineer. We bemoaned that municipal engineers had either lost their voices or had these taken away by organisational culture. We concluded that red tape and bureaucracy had effectively silenced engineers within local government, and that political leaders had allowed this to happen.
By Deon van Zyl
The audit culture of the AuditorGeneral and National Treasury was thought to be part of the problem, removing good-old engineering logic to be replaced instead by theoretical procurement ideals and decision making.
Three years later, these external role players still dictate the terms of operation for the municipal engineer. To date, no municipality has formally stood up to Treasury’s rules nor the Auditor-General’s box-ticking. While auditing is important, it can never be a purpose in itself; a clean audit neither guarantees service delivery nor places food on the table for the average citizen.
Recalibrating the conversation
But to argue that nothing has changed since
2021 is not quite true. A new crop of engineers are being attracted to local government, partly due to the salary packages that cannot be matched by the private sector during economic growth of less than 1%. But it is not just about money. Many newcomers are also attracted by the fact that local government is where large and complex capital projects are happening and, as engineers, they are now able to participate as clients rather than as consultants.
For the first time in years, large-scale capital projects are recognised as critical to addressing rapid urbanisation and the solution to years of infrastructure backlogs. And dynamic mayors are buying into the need to spend capital to secure a just and equitable future for all citizens.
The May 2024 election tells the story: no single political brand is entitled to votes. Politicians can no longer hide behind a political franchise (because let us remember, political parties are largely a franchise system with elected officials having to pay back a percentage of their monthly salaries to the franchise holder – the politician’s party). Using eloquent peroration no longer guarantees either protection of representation or a job.
Voters’ ring-side seats on engineering performance
Which brings us to local government elections in two years’ time. What differentiates local government from provincial and national is that citizens have a ring-side seat on the level of their municipality’s service delivery; they are less interested in the softer issues of local government, but very interested in the state of engineering services. Are roads overly congested, do sewers flush, and do stormwater systems reduce or increase flooding? Effective service delivery is what impacts citizens, and what will influence their votes in 2026. (As an aside, would it not be wonderful to see retired municipal engineers standing themselves for election as ward councillors to represent those citizens?)
Which brings us back to the municipal engineer and the need for their executives to recalibrate the conversation. Is a mayor focused on engineering services delivery purely paying lip service, or has the penny dropped that re-election is directly linked to the performance of the engineering services of each and every municipality?
JDA INVESTS IN JOHANNESBURG’S INNER CITY RENEWAL
The Goud Street PEU upgrade spanned from Marshall Street, across Main Street and Fox Street to Commissioner Street and included the installation of upgraded sidewalks, new street furniture (which includes bins and benches) and trees, with an overall focus on pedestrian safety and access
Goud Street, which lies in the inner city of the Johannesburg central business district, has been upgraded into a highquality environment and enhanced pedestrian experience, featuring wider sidewalks, public lighting, trees and improved stormwater systems.
An Inner City Core Public Environment Upgrade (PEU) project, this is the latest initiative completed by the Johannesburg Development Agency (JDA) in the Gandhi Square East Precinct. The latter has developed into both a popular tourist attraction and a busy urban hub of commercial and retail activity served by various types of public transport, including buses, taxis, and the Rea Vaya Bus Rapid Transport system.
Located in Ward 124, Goud Street measures 0,98km in length and has the distinction of being home to the Downtown Music Hub, a landmark
recording facility first opened in 1979 which is now officially recognised as part of the city's heritage.
Future planning
Longer-term, the R15 million Goud Street PEU revamp forms part of the city’s plans to invest over R800 million in capital projects into Region F, which encompasses the inner city. Here the JDA’s objective is to deliver these public infrastructure projects using labour-intensive methods with the aim of job creation and income generation through an Expanded Public Works Programme (EPWP) approach. For the Goud Street revitalisation, a total of seven SMMEs were involved at an expenditure of around R6 million.
“The successful upgrade of Goud Street reflects our commitment to revitalising Johannesburg’s inner city by creating spaces that are not only functional but also enhance the quality of life for
residents, businesses, and visitors,” says JDA’s CEO, Themba Mathibe.
“The transformation of this key area into a vibrant, pedestrian-friendly environment exemplifies our vision of fostering economic growth and urban renewal while honouring the rich heritage of our city,” Mathibe concludes.
NATURE
TO BUILD CLIMATE RESILIENCE IN SUB-SAHARAN AFRICA Working with
Leading consulting engineering and infrastructure advisory firm, Zutari, is collaborating with SUNCASA (Scaling Urban Nature-Based Solutions for Climate Adaptation in Sub-Saharan Africa) in a notable sustainability partnership.
SUNCASA is being implemented in several pilot cities and regions across Sub-Saharan Africa, chosen based on their vulnerability to climate impacts and potential for successful nature-based solution integration. These include Dire Dawe in Ethiopia, Kigali in Rwanda, and Johannesburg. The genderresponsive, nature-based solutions in the three cities are expected to benefit about 2,2 million people across three years.
“The SUNCASA initiative aligns closely with the existing priorities of the cities involved, such as mitigating the risk of flooding and heatwaves,” notes Dr James Cullis, Technical Director, Water at Zutari. By integrating natural processes and green infrastructure, such as urban forests, green roofs, and wetlands, SUNCASA seeks to mitigate such climate impacts while improving environmental health and social well-being.
SUNCASA’s research aims to identify the most effective nature-based solutions for specific urban contexts within Sub-Saharan Africa, considering local ecosystems, climate vulnerabilities, and socioeconomic conditions.
The project incorporates robust monitoring and evaluation mechanisms to assess the effectiveness of pilot solutions, emphasising continuous learning and refinement.
A key component is building local capacity and actively engaging communities, ensuring that solutions are sustainable and locally driven. SUNCASA fosters collaboration with local organisations to promote gender equality, social inclusion, and biodiversity conservation.
Ultimately, the goal of SUNCASA is to develop scalable models that integrate sustainable and adaptive practices into urban planning and development, fostering climateresilient cities across the region and beyond.
Johannesburg
initiatives
In Johannesburg, the initiative has made significant strides in revitalising the Jukskei River catchment area by removing invasive species and rehabilitating riverbanks. These efforts have already improved water quality and community health and are expected to reduce flood risks, mitigate
In Johannesburg, the SUNCASA initiative has made significant strides in revitalising the Jukskei River catchment area by removing invasive species and rehabilitating riverbanks
urban heat, protect biodiversity, and enhance local livelihoods.
As technical advisor, Zutari applies its broad expertise in various domains, including urban greening, transformative river management, ecological and hydrological monitoring, and stakeholder engagement. In collaboration with the City of Johannesburg and local partners like Gender CC, Water for the Future, and Alexander Water Warriors, a multidisciplinary approach is adopted to provide clean and safe water in pollutionaffected areas. This initiative is expected to benefit about 1.045 million people and create around a thousand eco-friendly jobs, mainly in disadvantaged communities.
“Being part of this initiative is deeply rewarding,” states Luyanda Mhlanga, civil engineer on the project. “We are privileged to use our technical skills to improve quality of life and sustainability for urban communities.”
SUNCASA recognises the necessity of working with nature, and with people, fostering deep collaboration to ensure communities are active participants and direct beneficiaries throughout the project lifecycle. By integrating expert knowledge, local insights, and resources with nature’s inherent wisdom, the programme will help to build resilient, thriving cities that can withstand the challenges of the future.
SUNCASA is a notable partnership to enhance climate resilience in Sub-Saharan Africa
Dr James Cullis, Technical Director, Water at Zutari
Rooftop gardens
In today's urban setting, dominated by townhouses, flats, and apartments, the urge to cultivate fresh, organic, and healthy food might frequently appear out of reach due to restricted space. However, the concept of “green roofs” or edible rooftop gardens is rapidly gaining popularity as urban residents look for new ways to include gardening into their daily life.
Effective rooftop gardens combine food production with environmental sustainability, which includes reduced rainfall runoff, heating and cooling requirements, biodiversity, aesthetic value, and air quality. As urbanisation intensifies, the availability of space per person decreases, driving the need for creative solutions like edible rooftop gardens. These gardens provide a sustainable, cost-effective source of fresh produce, offering health benefits.
While the concept of rooftop gardening is appealing, several critical factors must be considered to ensure success:
• Structural Integrity: Ensure that your roof can support the additional weight of soil, plants, and water. Consulting a structural engineer before starting your project is essential to prevent any structural damage.
• Waterproofing and Protection: To safeguard your existing roof, an additional protective layer is necessary unless you’re using trays or containers. This layer will prevent water damage and ensure the longevity of both your garden and your roof.
• Drainage: Proper drainage is crucial to avoid water accumulation, which can lead to roof damage and plant root rot. Incorporating Water Wise principles like using permeable
materials can enhance drainage and prevent excessive runoff.
• Roof Slope and Pitch: The slope of your roof is vital for both plant stability and water management. A steep slope can cause plants to slide off, while a flat roof may lead to water pooling. Designing with the right pitch ensures a safe and efficient garden setup.
• Plant Placement: Consider the orientation of your roof, local climate, and exposure to wind and shade. Position plants strategically to maximise sunlight and protect them from harsh conditions. Opt for hardy, drought-
tolerant species that thrive in rooftop environments.
• Wind Mitigation: In areas prone to strong winds, consider incorporating aesthetically pleasing windbreaks such as trellises or shade cloths. These not only protect your plants but also add a unique architectural element to your rooftop.
Rooftop gardens inherently align with Water Wise principles, particularly in their use of rainwater and prevention of stormwater runoff. By capturing and utilising rainwater, these gardens reduce the need for supplementary irrigation, conserving precious water resources. Additionally, the vegetation on green roofs slows down water runoff, minimising the impact on urban drainage systems and reducing the risk of flooding.
CEENEX HELPS BRING WATER TO THOUSANDS OF HOUSEHOLDS IN VERENA AND WOLVENKOP
Harnessing Ceenex’s extensive water engineering capabilities, Thembisile Hani Local Municipality (THLM) is bringing water directly to the homes of constituents who reside within Verena and Wolvenkop in Mpumalanga.
These towns continue to develop at a rapid pace as THLM releases land for development. Currently, about 23 000 people reside within these areas. Based upon Ceenex’s projections of a 1,85% growth factor over the next two decades, about 9 000 additional people will require basic services by 2044. These include a reliable, secure and safe supply of drinking water – a basic human right that is enshrined in the South African Constitution and one of the United Nations’ (UN’s) Sustainable Development Goals.
While these constituents can access water, doing so can be a very onerous process. This is time that could be more efficiently spent on other household duties, such as earning a livelihood and providing care to children and the elderly. Constituents have to walk over long distances to the closest community standpipes where they can stand in lengthy queues just to collect water. They then have to cart full jerry cans, each weighing up to 13 kg each, back to their dwellings.
This is a task that is often delegated to women who sometimes even have to carry 70 kg barrels on their backs or via wheelbarrows, depending on their water requirements. According to the UN, subSaharan Africa loses about 40 billion hours every year, the equivalent of France’s entire workforce, just collecting water.
At present, water demand in Verena and Wolvenkop stands at about 6,7 M ℓ which Ceenex has forecasted will about double
over the next 20 years as these towns continue to grow.
Build programme
Based on the consulting engineer’s quality water demand analysis, Ceenex was also appointed by THLM as the design engineer of a high-quality water reticulation system to deliver water directly to these households. Working alongside Ceenex, DKPB Construction commenced constructing the infrastructure in March 2024.
Although initially anticipated to be finalised within 24 months, this enterprising contractor has committed to completing the project eight months earlier. Therefore, by August 2025, about 3 000 households will be connected to the new water supply system.
Under the watch of seasoned Ceenex Project Manager, Kabelo Ringane, the project is more than 40% complete with all 62 dwellings in Verena B zone now connected and collecting water from standpipes on their properties. Households in this zone were able to access water upon practical completion of the connections. This approach will be adopted throughout the project to fast-track service delivery to these communities.
“There are a further four zones that need to be connected, namely Verena A, C and D, as well as Wolvenkop as an outlier. Verena A consists of 122 houses; Verena C 55 houses; and Verena D 1 823 houses. This is in addition to the 1 422 dwellings located in Wolvenkop,” Ringane explains. “One household consists of no less than four people, all of whom will be able to
1
3
access water in a convenient manner when we have completed the project.”
“Considering the significant time saved that can rather be spent on other meaningful activities, this project will have a large positive socio-economic impact. This includes empowering women who are overwhelmingly responsible for water for domestic use in their communities due to established gender roles. On average, one household in Verena and Wolvenkop requires 50 ℓ of water that needs to be collected from the closest available source and carted back to cook and clean,” Ringane continues.
In terms of the project, water will be distributed to the houses via a 75 mm
1 Water will be distributed to the houses via a 75 mm diameter unplasticised polyvinyl-chloride (UPVC) pipeline that is connected to a 110 mm diameter UPVC main-delivery line
2 The works are being led by main contractor, DKPB Construction
3 At present, water demand in Verena and Wolvenkop stands at about 6,7 M ℓ which Ceenex has forecasted will about double over the next 20 years as these towns continue to grow
diameter unplasticised polyvinyl-chloride (UPVC) pipeline that is connected to a 110 mm diameter UPVC main-delivery line. In turn, it will be fed by an existing 200 mm diameter bulk supply pipeline that supplies water from a 11 Mℓ reservoir in Gemsbokspruit to Verena. The pipeline currently has a capacity of 6 700 kℓ/s which will have to be doubled in subsequent phases, based on Ceenex’s water demand forecast.
Water metering
As part of this initial phase, water meters are also being installed on all of the properties. This is to ensure that all of the dwellings are receiving water and to develop end-use profiles. At present, communities in Verena and Wolvenkop are not being charged for water services. However, THLM intends eventually charging households for these services.
By placing a monetary value on this essential service, the municipality hopes to encourage responsible use in a water-stressed area. This while also providing the municipality with an important stream of revenue to ensure the sustainability of its operations and improve service delivery to constituents.
Construction challenges
The project has not been without its share of challenges, and more are anticipated as the work progresses. For example, a section of the pipeline needs to be constructed through an area with a perched water table. To avoid buoyancy forces, which could potentially damage the pipeline, drainage systems will have to be installed.
Furthermore, excavation for the pipelines is being undertaken in mountainous terrain which is, therefore, underlain with hard rock. As the project progresses, the contractor may have to deploy conventional and chemical blasting. This is in addition to the judicious use of excavators, bearing in mind the preference for labour-intensive construction methods to ensure that the project creates employment opportunities for community members.
Community participation
Notably, 21 members of the community have been employed to work alongside DKPB Construction. Two of these individuals are living with disabilities and 10 are women. This is in addition to the seven womenowned small, medium and micro enterprises (SMMEs) that have been sub-contracted to work on this project. They are complemented by a team of seven male-led SMMEs.
All Construction Industry Development Board (CIDB) Grade 1 contractors, they will undertake labour-based excavation and installation of the 75 mm pipeline to the properties; water meters; and taps. Furthermore, they will be tasked with all small concrete works, including the construction of the thrust blocks for the pipelines and the bases around the standpipes. The SMMEs have also been afforded the opportunity to complete their work scope in a month as opposed to two. In this way, they can free up the capacity that they need to take on additional work to grow their companies and scale the CIDB register.
To ensure integration with the larger THLM jurisdiction, 40% of the sub-contractors are from outside Verena and Wolvenkop.
All of the SMMEs have also committed to each hiring three members of the community for general work. This will create more than 60 short-term employment opportunities with focus again on ensuring equal participation by women.
Certainly, this approach demonstrates THLM’s commitment to playing its part in the meaningful transformation of the South African built environment sector through strategic preferential-procurement policies that also emphasise gender equality.
Notably, the project is also being managed by a very competent woman, Lizzy Molefe. The THLM Project Manager’s extensive built environment skills are being complemented by those of Siyabonga Kalipa, THLM Project Management Unit Manager; Technical Manager, Walter Mtshweni; and Municipal Manager, Dumisani Mahlangu.
In addition to bringing robust technical and leadership skills and experience to the project, THLM has also ensured strong community buy-in right from the outset. This social factor is just as important to project success as political support and technical expertise.
THLM Ward Councillor, Letseja Dikgale, and Acting Chief Financial Officer, Richard Makhubele, have been very hands-on by attending all project monthly meetings with the Project Steering Committee and then communicating updates timeously with community members. THLM’s open communication and transparent procurement policies have also helped to manage community expectations. To date, there has not been a single strike, protest or incident of extortion and violence by the so-called “construction mafia”, a growing problem in the country.
Certainly, the Fuduwa system deployed to select community members to work on the
project in an impartial way has also been very successful. However, the project is also providing a fertile training ground for young enterprising built environment professionals.
Ceenex, with the help of THLM, selected an industrious final year Vaal University of
and
By participating in this Ceenex corporate social investment programme, he is gaining the valuable workplace experience that he needs to attain his qualification.
Constituents have had to walk over long distances to the closest community standpipes where they can stand in lengthy queues
Furthermore, 23-year-old Luvoyo Khaba has been appointed to serve as Ceenex’s Resident Engineer on this project. The BTech graduate’s previous experience working in the contracting sector has placed him in very good stead on this project. As mentor, Ringane is supporting him in achieving his goals of completing a Bachelor of Engineering degree and registering as a Professional Engineer with the Engineering Council of South Africa.
“Certainly, I am very proud to once again be working with this longstanding Ceenex client on a project that is already uplifting community members during the construction stages. When we turn on all the taps, the community can also take pride in the fact that they helped THLM achieve this. They can, therefore, take ownership of their infrastructure and work closely with their municipality to ensure that it is always in good working condition,” Ringane concludes.
• Highly economical cost to volume ratio
• Easily transportable, especially for multiple tanks
• Easy assembly, even at elevated heights
• NO CRANES REQUIRED
• Robust steel tank with high life expectancy
• Replaceable liner allows for extended life
Technology BTech student, Thulani Musabo, to work alongside Ringane
his team.
SAVE WATER NOW – SUPPORT THE LESOTHO HIGHLANDS MAINTENANCE EFFORT!
As you might have heard, the vital and planned maintenance work of the transfer and delivery tunnels of the Lesotho Highlands Water Project (LHWP) has commenced from 01 October 2024 – 31 March 2025 . This exercise will ensure the continued flow of water to the Integrated Vaal River System (IVRS), from which millions of South Africans rely on as a daily source of water.
Over 780 million cubic metres (m3) of water is transferred annually from the LHWP to the IVRS, from which Rand Water extracts water to supply its customers. However, during the six-month maintenance period, water delivery will be temporarily reduced by 80 million m3. The Department of Water and Sanitation has assured Rand Water that the maintenance will have insignificant impact on the overall IVRS, as dams like Sterkfontein and others are currently full. However, Rand Water urges its customers to adopt water conservation practices that will help curb the ongoing high-water consumption and encourage the responsible use of water.
Here are some ways you can help conserve water everyday:
• Fix Leaks Quickly: A constantly dripping tap or a leaking toilet can result in an average daily water wastage of 30 to 60 litres. Ensure that all household leaks are repaired immediately.
• Shorten Your Showers: Reduce shower time to 5 minutes or less. This small change can save up to 80 - 100 litres per person per week!
• Install Water-Saving Devices: Low-flow showerheads, taps, and dual-flush toilets reduce water usage by up to 50%
• Reuse Greywater: The use of greywater provides us with an opportunity to use an average of approximately 35 – 234 litres (per person per day, depending on lifestyles) of greywater, which can be repurposed for garden irrigation or toilet flushing.
• Full Loads Only: Always run dishwashers and washing machines with full loads to maximise water efficiency.
• Sweep, Don’t Spray: Use a broom, not a hose, to clean outdoor areas like driveways and sidewalks.
• Watering Times: Water your garden in the early morning before 06:00 or late afternoon after 18:00 as this reduces water lost to evaporation.
• Cover Your Pool: The use of a pool cover can reduce water lost to evaporation by 70 - 95%, depending on the material used. Of the 14 400 litres we could potentially lose without a cover, for example, we could now save between 10 080 - 13 680 litres. Since water is essential to life, it is our collective duty to safeguard it. We can lessen the burden on our resources, protect future supply, and
maintain our prosperity as a country that prioritises conservation with your assistance. Together, we can make every drop matter!
HAMMANSKRAAL’S 50 MLD EMERGENCY WATER TREATMENT PLANT LEADS THE WAY ADDRESSING THE GAPS IN SOUTH AFRICA'S WATER AND SANITATION SECTORS
a new way of doing things, and a future where water security is certain.
Tecroveer is privileged to be at the forefront of this innovation and change, with the Hammanskraal Emergency Water Treatment Plant being a flagship project. This project showcases how the present can be turned into an opportunity that addresses both immediate and long-term water security needs.
A solution to many challenges
purpose-built manufacturing facility
Over the past few decades, South Africa's water and sanitation sectors have been faced with numerous challenges, such as urbanisation, population growth, corruption, gaps in forward planning, polluted rivers, water shortages, and a need for greater focus on future sustainability, among others.
According to the Blue and Green Drop reports – used by the Department of Water and Sanitation to assess the performance of water service authorities – the majority of the country’s infrastructure is now in critical condition, leaving South Africans deeply concerned about the future of water security.
The question is: How does one address the enormity of a problem such as this, where more than 50% of a country's water and sanitation infrastructure is seriously compromised?
Given the seriousness of this situation and the evidence at hand, declaring a state of emergency concerning the water and sanitation infrastructure situation – and collaborating with the private sector to address the crisis – would not be an unreasonable response from the government.
What is clear is that a different approach is needed. The slogan of the recent 2024 WISA conference in Durban spoke directly to this point, namely “Turning the Tide”. This theme reflects the urgent need for accelerated change to meet the water-related Sustainable Development Goals by 2030. The conference aimed to gather professionals and thought leaders to collaborate on innovative solutions for water management, governance, and sustainability.
The community of Hammanskraal has struggled with irregular access to water for years, and the recent cholera outbreak, which claimed several lives, highlighted the need for a long-term solution. During interviews, local residents expressed their urgent need for safe water and an end to having to allocate a large portion of their monthly income to purchase bottled water.
In January 2024, National and Local Government advocated for the construction of an Emergency 50 MLD Water Treatment Plant as an extension of the existing Magalies Water Board 40 MLD Klipdrift Plant. At a site meeting to assess progress, the statements by the Minister and the Mayor of Tshwane – about their commitment to work together – were encouraging, as was their determination to resist the influence of water and construction mafias.
Tecroveer’s Modular Water Treatment Technology was selected by ProPlan, the engineers, and Magalies Water Board,
The plant consists of four 12.5 MLD modular units, providing a total capacity of 50 MLD, making it one of the largest modular plants in the world, both in terms of individual unit size and total capacity
A future where water security is certain
While challenges can be uncomfortable, they demand attention, innovation, and action, which can lead to exciting opportunities for growth and development,
A
has been erected at Tecroveer’s factory in Glenhavie, where two 12.5 MLD units can be manufactured in parallel
and design and construction commenced with all urgency.
Plant process design
The plant consists of four 12.5 MLD modular units, providing a total capacity of 50 MLD, making it one of the largest modular plants in the world, both in terms of individual unit size and total capacity.
Innovation can often result in complexity, extra costs, long project durations, unreliability, and plants that are difficult to maintain and operate. However, the focus of Tecroveer’s team in developing the modular units has been the opposite, with simplicity, robustness, ease of operation, low cost, fast implementation, and affordability being the main goals.
desilting, continuous filtration, and disinfection – are all achieved within a single unit, without any interconnecting pipework or pumping. The total head loss over these steps is less than 1 metre.
The construction of the Hammanskraal plant is progressing well, with the first 12.5 MLD module expected to become operational in October 2024
Project impact and key elements of success
The design combines all traditional water treatment steps in a single modular unit, with capacities ranging from 1 MLD to the current largest of 12.5 MLD. The process steps – degritting, flocculation, dissolved air flotation,
Unlike traditional gravity filters, continuous filtration technology means there are no backwash pumps, no complex automation, no downtime during backwashing, and consistent water quality at all times. The units are simple, with bulk mixing and distribution achieved hydraulically, having only two automated valves and a power consumption of less than 2 kW per ML of water treated. The units are enclosed in a building with an overhead crane to accelerate installation and for ongoing maintenance.
Local fabrication
A purpose-built manufacturing facility has been erected at Tecroveer’s factory in Glenhavie, where two 12.5 MLD units can be manufactured in parallel. Thanks to the pre-engineered modular design and the purpose-built manufacturing facility, the time from order placement to delivering safe and pure water is achieved in an unprecedented four to five months.
Apart from mechanical items such as gearboxes the modules are 100% locally implemented and manufactured.
These large modular units are set to make a significant impact in the water and sanitation sectors, allowing for the construction of significantly larger plants than was historically possible for modular designs, and at a fraction of the cost and implementation time.
While the innovative modular design and the associated agile project management processes are key elements in the success of this emergency intervention, they are not the only factor. The collaboration, openness, integrity, clear intention, commitment, and vision of all parties involved – from National and Local Government to Magalies Water Board, ProPlan, Tecroveer, community stakeholders, and the people of Hammanskraal – have been equally vital. Without this collective effort, the project could never have materialised or been completed in such record time.
A positive future for SA water and sanitation infrastructure
The Hammanskraal Emergency Water Treatment Project is proof that government, authorities, the private sector, and communities do have the local skills and vision to work together to solve the present crisis in South Africa’s water and sanitation infrastructure, “One project at a time.”
At Tecroveer we see a future where our children play in the pristine water of our rivers and oceans, and drink safe and pure water, straight from the tap. That is why We Clean Water.
The construction of the Hammanskraal plant is progressing well, with the first 12.5 MLD module expected to become operational in October 2024 – just eight months after the tender submission – less time than it typically takes to complete the tender adjudication process! www.tecroveer.co.za
An artist’s impression of the Hammanskraal 50 MLD Emergency Water Treatment Plant
A leader in the construction, operation and maintenance of bulk raw water infrastructure
Since 2002, the Lebalelo Water User Association (LWUA) has self-financed, constructed and successfully operated and maintained its infrastructure. Our track record speaks for itself: uninterrupted water supply, zero fatalities since inception and less than 1% annual water loss.
Pioneering a public-private collaboration model for developing regional linear and utility infrastructure
LWUA is implementing the R25 billion (capex) Olifants Management Model Programme (OMMP), a 50:50 collaboration between Government and the private sector to fast-track the construction of bulk raw and potable water infrastructure in Sekhukhune and Mogalakwena, which in future will enhance water supply to Polokwane. This collaborative model holds promise for similar large-scale projects in sectors such as energy and transport.
Enabling large-scale, commercial mining in the Eastern Limb of the Bushveld Igneous Complex
Large-scale commercial mining of chrome and PGMs would not have been possible in the Eastern Limb of the Bushveld Igneous Complex (BIC) in Sekhukhune, Limpopo without the uninterrupted bulk raw water that we have supplied for the last two decades. Through the OMMP we are expanding into the Northern Limb of the BIC.
Driving sustainable socio-economic growth in every community where we operate
We are making a meaningful impact in our areas of operation, while delivering on our mandate, through localised infrastructure and operational spend, and by implementing key socio-economic development initiatives in host communities.
Ekulindeni treatment works refurbishment uplifts community
The refurbishment of the Ekulindeni Water Treatment Works will address critical water supply issues and improve access to clean drinking water in the Chief Albert Luthuli Local Municipality area. Residents currently face challenges due to inadequate clean water supply, often relying on rationed water.
The refurbishment project commenced in November 2023 for scheduled completion in October 2024. It aims to replace outdated infrastructure and obsolete equipment, while also repairing broken components.
“The refurbishment project is designed to achieve a high Blue Drop score, indicating that the water supplied will meet stringent safety and quality standards. This will help reduce waterborne diseases, which are prevalent in areas with poor water quality, thereby improving the overall health and well-being of the community,” notes Chalmers Pagiwa, MD of Lubisi Consulting Engineers, which was appointed for the project.
Works components
Key activities in the refurbishment include finalising the construction of a concrete weir across the Komati River to optimise water abstraction and upgrading the main treatment works building – including the installation of a new polymer dosing system, safety equipment and a water quality testing laboratory.
Another major component of the project includes the refurbishment of clarifiers and filters to improve water treatment processes. The clarifiers are located at a depth of 6 m, and the contractor needed to comply with the detailed plan designed by Lubisi Consulting Engineers to complete this complex aspect of the project successfully.
Lubisi Consulting Engineers has also been tasked with installing two new submersible pumps and optimising the raw water pump station. “The refurbishment of the raw water pump station has been challenging during times of high river flow as the pump station is designed with a wet sump,” Pagiwa explains.
The project also promotes long-term community development. “By investing in infrastructure, the municipality is taking a significant step towards alleviating poverty and enhancing the quality of life for residents. This project is not just about water; it’s about creating equal access to resources that empower communities and foster sustainable development,” Pagiwa concludes.
July and August 2024 were two busy months for the city's Water and Sanitation Directorate teams as they kicked off a series of projects for the current financial year
CAPE TOWN PRIORITISES AGEING PIPE REPLACEMENTS
During the first two months of its 2024/2025 financial year, the City of Cape Town replaced around 26 409 m of pipeline in terms of its asset renewal initiatives. This comes off the back of a proactive infrastructure maintenance and upgrade programme for the previous financial year where the city’s Water and Sanitation Directorate successfully replaced 111% of water pipes and 96% of sewer pipes during several planned projects across the metro.
Replacing aged water and sanitation infrastructure is a key strategic objective and the city is working hard to action its Water Strategy. This aims to ensure high-quality drinking water into the future and a reliable wastewater service to help provide a dignified service to citizens, as well as a healthy environment.
During July and August 2024, some 7 104 m of water pipe was replaced in Bloubergstrand, Eversdal Heights, Wellway Park, Avondale, Atlantis, Loevenstein, Flamingo Vlei, Somerset West, Strand, Retreat, Bellville Phase 2 and Parow. In turn, over 19 305 m of sewer pipe was replaced in Claremont, Parow, Parow North, Gugelethu, Sacks Circle and Bellville, Brackenfell, Stikland, Southfield, Eerste River, Strand, Somerset West and Belhar.
“Our pipe replacement programme will remain a top priority for the city to ensure our water and sewer infrastructure is in tip-top shape, to reduce the number of pipe bursts and sewer spills and to provide efficient water and sanitation services,” says Councillor Zahid Badroodien, the city's Mayoral Committee Member for Water and Sanitation.
For the 2024/2025 financial year, the City is investing R323 million to ambitiously once again aim to replace 50 000 m of water pipes and 100 000 m of sewer pipes on designated projects city-wide.
Bulk excavations for weir foundations
Concrete works on weir
COLLABORATIVE BIM IMPLEMENTATION
ESTABLISHING BEST PRACTICE GUIDELINES FOR DIGITAL INFRASTRUCTURE DELIVERY IN SOUTH AFRICA
The BIMCommunityAfrica held its 5 th Convention for a Digital eSouth Africa (CoDE•SA) in October 2024 under the theme “Building the Machine – practical solutions towards digital transformation of the Engineering and Built Environment.” This set the stage for transformative digital adoption in South Africa’s construction industry. By Amanda Filtane and Richard Matchett, BIMCommunityAfrica
The focus was clear: to “build the machine” for effective BIM implementation three pivotal priority areas need to be addressed, namely policy, process, and technology. These are all interconnected and essential components of the machine for achieving a cohesive and future-ready built environment that can adapt to digital project delivery practices. Digital infrastructure efficiencies are essential for South Africa to drive economic growth, manage urbanisation, and improve sustainability.
The country’s infrastructure sector, critical for development, often faces delays and cost overruns due to outdated processes. Continued demand for efficient infrastructure, and digital solutions like BIM enable better planning, delivery and operations through resource optimisation and virtual simulations models. Implementing sustainable practices is also crucial for South Africa, as digital tools aid
BIMCommunityAfrica held its 5th Convention for a Digital eSouth Africa (CoDE•SA) in October 2024, which was attended by practitioners from across the built environment industry
in the lifecycle management and maintenance of assets.
Therefore, the purpose of the convention, through guided conversations, engagements, International Standards and best practice examples, was to collectively map out the specific requirements to realistically support BIM adoption going forward.
Skills, staffing, professionalisation and standard reform (Policy field) Addressing the skills gap is fundamental. Research shows that a significant barrier to BIM adoption in South Africa is the shortage of qualified personnel and training opportunities. Studies highlight that firms often lack structured BIM education and professional development pathways, which limits their ability to integrate digital processes effectively. As seen in global best practices, formal certifications and competency frameworks are essential to professionalise and standardise BIM skills within the industry.
Establishing continuous training programmes and aligning them with academic curricula will create a consistent pipeline of BIM-ready professionals. This
integration ensures the construction workforce is not only familiar with BIM tools, but also adept at utilising them in practical settings. Policies must also be updated to incorporate BIM practices into municipal standards and project procurement processes. By mandating BIM in municipal projects, municipalities can lead by example, demonstrating the efficiency and transparency that digital processes bring. Engagement with regulatory bodies like the Construction Industry Development Board (CIDB) will be pivotal in setting these standards and gaining industry-wide buy-in for policy changes.
Clients, asset owners and facilities managers: Collaborative contracting and procurement requirements (Process field)
Collaboration is another cornerstone for BIM's success. Contractual frameworks need to evolve to accommodate digital information sharing, enabling a collaborative environment where asset managers, facility managers, designers, and contractors work seamlessly. Evidence from local studies suggests that current procurement processes are not aligned with the demands of digital integration, making it necessary for clients to specify BIM requirements in project tenders and contracts.
Information management and open libraries (Technology field)
Shared information resources, including open libraries of digital content tailored to South Africa's needs, are crucial for scaling BIM. Establishing an open library would standardise information and improve consistency across projects, reducing rework and enhancing efficiency. Information management must also
align with best practices to ensure data is accessible, interoperable, and reliable.
To truly build a functional “machine” technological frameworks need to prioritise interoperability and open-source approaches. This ensures that different software platforms can communicate, reducing silos and enabling cohesive project management. An emphasis on open libraries will also support localised content creation, enhancing the relevance of digital models to South African contexts.
Action plan: Working groups and collaborative efforts
The convention concluded with the establishment of working groups to focus on each priority area. These groups will produce tangible outputs by the next meeting in March 2025. To ensure wider participation and industry alignment, awareness letters will also be sent to relevant organisations – public and private, councils, as well as clients, to garner support and an action agenda towards South Africa’s digital (BIM) transformation.
Conclusion
The BIMCommunityAfrica’s strategic approach aligns with international best practices while
tailoring solutions to South Africa’s unique context. By addressing skills development, aligning procurement processes, and establishing a foundation for shared information management, we are collaboratively setting the stage for a digitally transformed and efficient construction industry.
The progress made through these conventions and subsequent actions is documented and shared via the BIMCommunityAfrica website (www.bimcommunity.africa/bimcodesa), providing a platform for ongoing learning and development across the industry.
The strength of the collective voice within BIMCommunityAfrica is instrumental in driving industry-wide transformation through the BIM CoDE•SA initiative. With participants including clients, consultants, contractors,
Effective BIM implementation requires addressing three pivotal areas, namely process, policy, and technology
regulatory bodies, researchers, educational institutions, and voluntary associations, the initiative encompasses the full spectrum of industry expertise and perspectives. This collaborative and inclusive environment enables the co-creation of best practice guidelines that are comprehensive and responsive to the needs of all stakeholders. By uniting such a diverse range of voices, as an open, sharing organisation, BIMCommunityAfrica ensures that the standards and methodologies developed are practical, evidence-based, and aligned with the realities of the South African construction landscape. This collective engagement builds momentum, setting the foundation for the widespread adoption of digital practices and fostering excellence in infrastructure design, delivery and operations.
For further information, contact angela@bimcommunity.africa
Dr Amanda Filtane, Lecturer, Department of Construction Economics and Management, University of Cape Town
Richard Matchett, Lead: Digital at Zutari
Kobelco excavator is the answer to Mkhondo’s dump problem
The town of Mkhondo, formerly known as Piet Retief, lies in a wonderfully wooded area of the Mpumalanga province. However, by early 2023 it faced a problem: its solid waste dump site was fast becoming unmanageable unless drastic control measures were urgently found.
It was thought that a big part of such control measures involved buying expensive earthmoving equipment.
“We were really concerned about this problem and even more so when it was suggested that what we needed to fix the solid waste site was a large bulldozer, which is a really expensive machine,” says Zoe Mbatha, Senior Manager: Assets and Logistics for the Mkhondo Local Municipality.
“Our concern stemmed from seeing waste being blown onto the N2 national road and into
villages surrounding the town, as this seemed like a municipality that didn’t care, where in fact we do care a great deal.”
The Mkhondo Local Municipality encompasses the nearby towns of Amsterdam and Driefontein and is home to over 255 000 people, according to the most recent census. The municipality also forms part of the greater Gert Sibande District Municipality, which is headquartered in Ermelo.
Like most municipalities, Mkhondo Local Municipality’s responsibilities relate to maintaining gravel and tarred roads, public spaces, sports fields, cemeteries, and solid waste dump sites, as well as the supply of potable water and water reticulation services.
Many of the amenities mentioned come under the direct control of the Environmental Department within the municipality and here we find Vusi Dube, the Senior Manager: Environmental Management.
Needs analysis
“When we realised we needed to take urgent action with the management of the solid waste dump site, we conducted a needs analysis. Our first thought was that a bulldozer would be the correct solution as it would be heavy enough to compact the waste and have the blade for bringing in layers of soil that could also be compacted on top of the layers of waste,” he explains.
“However, when consulting with our colleagues in other departments, the thought was that equipment such as an excavator would serve a wider purpose for the other departments
Vusi Dube (left) Senior Manager: Environmental Management, Mkhondo Local Municipality, with Zoe Mbatha (centre) Senior Manager: Assets and Logistics, Mkhondo Local Municipality, and Fortune Matsobane (right) Bell Equipment Sales Representative
like water, electricity, and infrastructure and a supplier for an excavator was sought.”
Fortunately, help was at hand in the form of an RT57 supplier contract that the Mkhondo Local Municipality could leverage with Bell Equipment.
The municipality had in the past bought two Bell graders and a backhoe loader and was familiar with the company, as Bell Equipment has a branch in Mkhondo that had regularly serviced the machines.
“We were also familiar with Fortune Matsobane, Bell Equipment’s knowledgeable Public Sector Sales Representative who calls on us regularly,” Vusi continues. “Fortune suggested we consider a Kobelco SK300LC-10 excavator, which would easily rake up the waste material, be heavy enough to compact it, and be able to spread soil over the compacted layers.”
“Bell Equipment came in at a very competitive price. The fact that the company has a branch with a mechanic and a full complement of replacement parts and service kits in our town also scored heavily in its favour,” Vusi adds.
The decision was taken that a Kobelco SK300LC-10 excavator would be the best multipurpose tool, and the machine was subsequently ordered and delivered in October 2023.
Operation and control
“We fortunately had a trained operator in Sibusiso McDonald but we’re planning on training at least three or four more operators on the Kobelco excavator should Sibusiso be ill or not available,” Vusi explains. “Needless to say, the new Kobelco excavator’s first deployment was at the solid waste dump site and here it has really shown its capabilities.”
According to Vusi, Sibusiso reports that the Kobelco SK300LC-10 excavator’s controls are smooth and instantly responsive, making it easy to
operate and cutting down on operator fatigue. The engine noise is minimal while the hydraulic flows are excellent, as reflected in the fuel consumption figures of around 7,8 litres an hour, which has been a pleasant surprise for everyone concerned.
“This Kobelco SK300LC-10 excavator was an excellent choice and from my experience I can tell you that within the short timeframe we’ve had the machine, we’ve managed to extend the life of our solid waste dump site by at least three years,” Vusi enthuses.
The last word though belongs to Zoe as she says: “We can now be proud of our municipal dump site again as we’ve contained the waste with the Kobelco excavator. This really is a working example of good service delivery in action.”
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Rebuilding a historic Stellenbosch bridge with precast concrete beams
The old bridge over the Plankenbrug River (formerly Dwars River) in Stellenbosch was rebuilt by Martin & East with nine precast concrete beams supplied by Concrete Manufacturers Association member, Cape Concrete. Designed by infrastructure consultancy, AECOM, the first phase was completed in August 2022 and the second and final one during the first quarter of 2023.
The new bridge provides improved access to Bosman’s Crossing, a burgeoning residential, commercial and light-industrial precinct situated in the old KWV Industrial Park immediately east of the bridge.
The site’s first bridge appeared in 1691 on what was the old wagon road “Highway”, the earliest formal route into Stellenbosch, and one of the first, if not the first, bridges to have been built in South Africa. The site is considered an integral and authentic piece of Stellenbosch and indeed Cape history, and over the years the bridge was either upgraded or rebuilt.
The area’s known historical links can be traced well beyond the 17th Century, in fact to the early Stone Age period some two million years ago. A monument just off the western approach to the bridge marks the point where stone implements, including a Palaeolithic quartzite axe, were discovered in 1899.
The new bridge replaced the one which was erected in stone and in-situ concrete during the early part of the 20 th Century. It was upgraded to a narrow double-lane thoroughfare in the 1950s when its abutments and central stone pier were enlarged and strengthened. During the 1960s the structure gradually fell
out of use as one of the main routes into Stellenbosch after the construction of the Adam Tas Road Bridge over the Plankenbrug River, which provided more direct and faster access. And from the first decade of the new millennium onwards Distillery Road was closed as a route into town and only served Bosman’s Crossing, which it still does today. However, the growth of the Bosman’s Crossing precinct during the second decade of the 2020s; an increase in traffic and the deteriorating condition of the bridge, prompted the Stellenbosch Municipality to investigate widening and strengthening options.
Design proposals and heritage factors AECOM was appointed to inspect the bridge in 2020 and found the structure to be neither safe nor practical for existing and anticipated traffic volumes. Based on this finding AECOM was commissioned to evaluate alternatives which compared repair, rehabilitation and upgrading options. And because of the site’s possible historic significance, the council also appointed a heritage architect to compile a report to be used as a guideline for the rebuild.
Prepared by Rennie Scurr Adendorff Architects and CTS Heritage in consultation with Heritage Western Cape, the report was submitted together with the permit application to upgrade the bridge. Covering the heritage, archaeological, landscape and contextual significance of the site, the report recommended that the new design should respond to the semi-rural character of its immediate surroundings rather than the commercial and residential aspects of Bosman's Crossing.
The second beam in Phase 1 is lowered into position onto the first abutment lift
Several design proposals were considered in the report. In each case, the improvements required to improve traffic flow and safety were assessed in terms of the bridge’s alignment and positioning; its component features; load bearing capacity of the old elements; river through-flow and flooding; and the need to limit any potential damage to the surrounding landscape and environment.
The engineering team tabled six design proposals that were workshopped with the heritage team. Two options which adhered to both heritage and functional requirements were adopted and developed further by the engineering team. One proposed retaining the central stone pier as a non-structural component in a single-span bridge and the other advanced a two-span structure with a functional central pier.
Bearing capacity
AECOM’s analysis confirmed that the bearing capacity of the existing central pier would be significantly exceeded if it were incorporated structurally in the proposed two-span design and would require another row of piles and further structural modifications. By contrast, in a single-span design – using prestressed precast concrete beams supported by new abutments – the central pier could be retained in a non-structural capacity, and it was this solution which was finally chosen.
The retention of the pier was recommended because, as with the old abutments, it predates the existing upper structure and could therefore serve as a visual link to the old stone bridge. An additional heritage aspect was the reinstatement of four existing handrail bollards, which serve as entry markers at either end of the bridge.
Eight metres wide, kerb-to-kerb, and 22,5 m long (2 m longer than the old bridge), the new bridge accommodates two lanes of traffic. In addition, cantilevered sections on either side of the vehicle deck were built for pedestrians and cyclists. Besides their functional purpose, the sections enhance the visibility of the central pier and reflect the character of the old bridge.
The new bridge was designed by AECOM bridge engineer, Heinrich van Wijk, who proposed a precast beam design primarily because it saved time, reduced the risk of flood damage to formwork staging, and limited construction debris falling into the riverbed.
“In a cast in-situ bridge option, there is an element of flood risk when staging formwork above a riverbed. Instead, we chose to specify
Workers insert rebar through sleeves situated in the beams’ lower web sections
The soffit sides of Phase 1 beams and the old central pier
The edge beam in Phase 1 is lowered into position
a precast construction technique, which limits disturbance in the riverbed and enhanced our application to the Department of Water and Sanitation for a water-use license,” said van Wijk.
Van Wijk’s design adheres to the South African bridge design code of TMH7 for NA and NB loads. One of the design constraints was the need to keep the bridge open during construction, which is why it was built in two phases. Apart from 1,5 m wide edging – which was demolished – the old bridge was left intact during the construction of Phase 1 and was only fully demolished once Phase 1 was opened to traffic.
Integral monolithic design
“The abutments and deck were built in an integral monolithic design, unlike conventional bridges which are mounted on bearings with expansions joints at either end. The integral design approach allows the free articulation of the deck without imposing significant stresses on the abutments. Thermal expansion and contraction are the primary source of movement (elongation and shortening) and the magnitude of this movement is directly related to the length of the deck,” Van Wijk continued.
“For shorter decks, conventional expansion joints are not needed. Instead,
thermal expansion and contraction can be accommodated by buried joints located at either end of the bridge, which allows for the small movement of the flexible abutments.
“Bank pad abutments were cast onto a single row of piles in two lifts. The first abutments were cast above new piles, which varied in depth between 13 m and 19 m, at either abutment end. The pile diameters were designed with sufficient flexibility to accommodate deck movement, and the backends of the abutments were backfilled with rounded aggregate, which allows for ratcheting movement within the fill and prevents the build-up of stresses behind the abutment.”
Precast installation and piling Cape Concrete cast nine 22,8 m prestressed beams for the new structure: seven internal beams weighing 25 tonnes apiece; and two edge beams at 35 tonnes each. The edge beams are non-symmetrical with thicker sides and flat face finishes. Four beams were used in the construction of Phase 1 on the southern side of the bridge and five were used for Phase 2 on the northern section. Both edge beams were designed to support the cantilevered walkways with protruding transverse pull-out bars.
Martin & East construction manager, Ricardo De Sa said that a temporary barrier was placed on the old bridge during construction of Phase 1. “Once the piles had been sunk, seven in Phase 1 and six in Phase 2, they were trimmed to the bottom of the foundation level before the first-lift abutments were cast. The second lifts act as diaphragm beams, tying all the precast beams together at either end of the bridge. Moreover, we cast concrete jockey slabs between the second abutments and the feeder road sections at each end to act as an interface between the solid concrete of the bridge deck and the more flexible road surface,” said De Sa.
When the first-lift abutments had reached the requisite seven-day strength, the precast beams were lowered onto temporary steel bearings which had been cast into the first abutment lifts of both phases. In addition, matching bearing steel plates were cast into the beams’ soffit sides. After being lowered into position, the beams were tied together at the bottom of the lower beam flanges with transverse reinforcing, which was covered with a 150 mm layer of in-situ concrete.
The installed beams were capped with a permanent Nutec formwork and reinforcing for the 175-250 mm cast in-situ bridge deck. The deck was cast with protruding rebar to tie into and support the walkways’ cantilevered reinforcing.
“Apart from some minor staging at each end of the bridge, the walkways were constructed without ground supported staging due to environmental concerns. This meant we had to come up with an alternative method of supporting and constructing the cantilevered platform,” De Sa continued.
“We opted for inverted steel-girder T-shaped suspension brackets, designed and manufactured by Formscaff, from which the support-work and formwork could be hung. The brackets, which extended 2,4 m off the edge of the deck, were mounted on two pivotpoint jacks.”
In addition, the brackets’ horizontal sections were secured to the underside of the deck with dywidag bars, and once all 24 T-brackets had been attached to the deck they were linked together with steel girders and poles to form an integrated support unit. Girder sections were also attached to the underside of the deck to support the Econoform panels used for casting the walkways’ sloped soffit surface.
Transverse cantilever support
Six transverse cantilever beams support each walkway slab. They include voids in the concrete to save weight and make provision for future service pipes. The cantilever beam reinforcing was spliced together with the Y20 rebar rods which had been cast into the top deck. They were also spliced with R20 inclined pull-out rebar, which extended from the bottom of the edge beams.
Additional formwork support was provided by tension cabling, which were attached to the top of the vertical bracket sections and the lower support girders on the one side, and from the top of the bracket sections and the T-shaped suspension bracketing at the Phase 1 walkway mounted on pivotpoint jacks
The underside girders and Econoform panelling
end of horizontal girders on the deck side. Once the walkway concrete attained an early strength of 60% of the required 40 MPa rating, the cabling was de-tensioned.
After all the support work had been removed, a further 20 mm of concrete was added to the top surfaces of the walkways, rendering them flush with the 40 mm premix layer on the bridge deck. This additional layer includes several service ducts and slopes at 1,5% for stormwater drainage. The bridge itself slopes at 1% from west to east for drainage.
M-type beams
The M-type beams were cast at Cape Concrete’s yard in Cape Town as a portal framework based on a bending schedule and
rebar drawings supplied by AECOM. They comprise a wide bottom flange, a narrow web portion and a flared upper flange section.
“We used a W50 mix with a super plasticiser in a 100 slump flowable concrete, which complied with three durability criteria: oxygen permeability, water sorptivity, and chloride conductivity,” said Cape Concrete director Johan Nel. “The plasticiser reduced water consumption and gave us better workability. What’s more, we achieved a transfer strength of 40 MPa which was reached in 18 hours using the high-strength mix design and steam curing.”
After de-tensioning, the beams assumed a vertical positive camber of between 15-20 mm,
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but once they were positioned on the bridge and the in-situ deck slab had been cast, they assumed a neutral camber.
“Reinforcing is congested when using prestressed strands, which is why we used a 13 mm stone in the mix. It is vital for the concrete to flow through the rebar and fill the entire structure without air pockets, and smaller stones facilitate this process. We used external vibrators and pokers to remove all the air, but we only used pokers on the top flange sections,” Nel continued.
“One of the plusses in M-type beam casting is that the bottom flange dimensions remain constant. If larger spans are required, one simply adjusts the web or top flange depths,” Nel concluded.
Water Institute of Southern Africa wisa@wisa.org.za
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Survey reveals growing acceptance of adjudication outcomes
Adjudication in South Africa’s construction sector is resulting in more settlements between parties during the adjudication process, indicating a new trend in dispute resolution.
This is according to construction law specialist MDA Attorneys, on the release of their annual adjudication survey results. These are based on the many adjudications conducted by the firm during 2023.
Euan Massey, MDA Attorneys director, says, “In the past, it was rare for parties to reach a settlement during adjudication proceedings, but we are seeing the start of a new trend, with settlements reached in just over 13% of our adjudications during the period compared to zero in previous years.”
While there were fewer adjudications year-on-year, the value of the disputes referred for adjudication increased significantly. Almost half of the disputes had a monetary value of up to R5 million, 13% fell within the range of R5 million to R10 million, and around 50% had a monetary value between R10 million and R50 million.
Nature of disputes
Interestingly, there were no claims for defective work and disputes on the enforcement of contractual rights were 25% lower than 2022. Continuing the trend in previous annual surveys, the most common disputes referred to adjudication were claims for extensions of time and time-related costs, followed by claims for payment of outstanding monies/incorrect certification.
Of the final adjudication decisions reached during the period, the vast majority were accepted by the parties. “This is an indication that the adjudication procedure is robust. Industry is confident in the success of adjudication, to the extent that there were no hearings during the period, in stark contrast to the early days of adjudication when hearings were common,” says Massey.
In employer/contractor disputes, decisions were mostly in favour of the contractor, which is unsurprising as the contractor is the party that typically refers disputes to adjudication.
Change in construction contracts under dispute
There are several standard form contracts commonly used in the construction sector. Whereas the highest-ranking contract causing disputes has been the NEC Suite, this year the largest portion of the contracts creating disputes is the JBCC, which is mostly used in building projects. This aligns with the higher number of building projects under adjudication during the period.
Also noteworthy is that no disputes have been declared under the GCC, which may be an indication of fewerGCC related contracts being awarded by municipalities.
The skills challenge: What must be done to get it right?
South Africa is grappling with a significant skills challenge, evidenced by a staggering 33,5% unemployment rate in the second quarter of 2024, according to Stats SA, as well as an escalating shortage of competent technical skills. The pressing question is: what actions must we take to tackle the dual issues of high unemployment, especially among the youth, and the shortage of engineering skills?
By Chris Campbell
This issue is not unique to us. The skills challenge is a global issue, but each country needs to find its unique solutions to solve the challenge. Despite not being alone in this struggle, our approach has not been effective. There is a troubling trend highlighted in CESA’s Bi-Annual Capacity and Economic Survey of December 2023: an uptick in migration patterns with highly skilled South African engineers leaving for the United Kingdom, the United States, and Australia. These cyclical migration patterns are driven by political and policy uncertainty, among other factors, reminiscent of the post-1994 era.
Addressing the reasons for this migration is crucial. The primary concern is safety and security, both personal and professional. We cannot surrender to organised crime. Reports suggest that government entities have capitulated to the construction mafia, inflating project costs to account for criminal activities. Our country cannot afford such excesses in infrastructure development. Additionally, citizens face the high cost of personal safety.
The second concern is the high cost of education. Many learners attend private schools to receive a quality education, enabling university entry. We must fix our public education system, starting with Early Childhood Development (ECD). Currently,
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our focus and spending is skewed towards university education, neglecting the foundational ECD. We also need to address the failures in our Basic Education System.
Keeping pace with technology Is our education system equipped to handle the technological future? For those who pass matric, there is an over-emphasis on academic education, with little focus on vocational training. Universities teach critical thinking, but not practical skills. The lack of vocational training, previously addressed by the successful Technikon system, is a significant gap. This system combined theory and practical application but was discontinued, leaving only TVET colleges or universities as options.
We face a total mismatch of skills and must address the skills challenge holistically by creating a pipeline starting with quality Basic Education. We are not doing enough to prepare students for technologically advanced careers.
The third challenge is the cyclical nature of infrastructure development, resulting in a “feast or famine” scenario for companies. During lean periods, technical skills are lost to other countries or industries. We call on the government to address this through careful planning of our project pipeline, stating that we need a steady flow of projects to retain our technical skills within the country.
There are beacons of hope. The Western Cape government has created an environment where technical professionals are respected and utilised for their competencies, attracting private sector individuals. This is evidenced in the professional management and maintenance of the province’s infrastructure. The Western Cape's success shows what can be achieved with the right environment and respect for professional skills.
Given our current situation, there is no quick fix. We need a comprehensive national plan involving all stakeholders. Many individuals have the wisdom and aspiration to assist. Meeting our challenges requires collaboration between the public and private sectors, supported by strong political will.
Chris Campbell, CEO of Consulting Engineers South Africa (CESA)
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