2017/2018 Water relief project for drought stricken Hantam Karoo town

The small town of Loeriesfontein in Hantam Karoo, Northern Cape has a population of approximately 3 200, and is situated about 450 km from ASLA’s offices in Strand. In early 2017, the drought-stricken municipality, that is entirely dependent on ground water, was at the brink of having no potable water in town. Following exploration drilling during 2014 and 2015, the nearest possible water supply was located approximately thirty kilometres away, on a sheep farm called Rheeboksfontein. A temporary, overland pipeline, running on the Western access road (along the Nieuwoudtville and Loeriesfontein Road) would provide an emergency supply of water from three solar powered borehole stations and additional 3 solar / generator booster pump stations, while a permanent underground pipeline was constructed along the eastern access to Loeriesfontein, along the Calvinia Road.

ASLA was employed as the civil works and lead contractor on this Department of Water & Sanitation project, and the professional team included BVi Consulting Engineers, EnviroAfrica and GEOSS South Africa. ASLA subcontracted the mechanical work to Hidro-Tech Systems, the electrical control and instrumentation was undertaken by Woodrow Engineering, the MV powerlines and transformers installed by EMC Reticulation, and the telemetry system by Spectrum Communications.

“The 16-month long bulk water supply contract was a multiple discipline project, located on a remote greenfield site, and there was absolutely nothing except farmland between the boreholes and Loeriesfontein,” explains ASLA contract manager Henry Zurnamer. “Our scope of work, in addition to maintaining and operating an emergency, above-ground, 33km temporary pipeline, was to construct a permanent underground pipeline and all associated infrastructure which included a water reservoir, treatment building and water conditioning plant.  The contract stipulated that ASLA had to ensure that 150 000 litres of water reached the town every day, seven days a week during the construction period.” When the temporary system failed to deliver sufficient volumes ASLA used trucks from a local transport company to haul water from Nieuwoudtville.

Temporary pipeline

The construction of the temporary rising main commenced in 2016 and was laid along the main road between the village of Nieuwoudtville and Loeriesfontein (15km tar and 18km gravel). The 33km-long HDPE pipeline was connected to three boreholes and laid next to the access road from the Western side. The average day-time Karoo temperature is around 28 degrees and can peak up to 40 degrees Celsius. This would heat the water inside the pipes to a temperature that caused multiple pump failures and was resolved by insulating the HDPE pipe with bidim and  sisalation.

Once the permanent line was commissioned, the temporary pipe was cut up into fifty-metre pieces and rolled up by an ASLA designed and manufactured pipe recovery and coiling machine. The complete 33 kms of pipe was rolled-up and delivered to Calvinia, for future use by the municipality.

Permanent pipeline

The permanent line was constructed along the Eastern access road to Calvinia. It was constructed parallel to the Calvinia / Loeriesfontein dirt road and ASLA constructed a 22km long,14m wide corridor. To preserve the environment all work had to be conducted within this 22km corridor, which also became the only access route for construction work.

“We undertook a number of disciplines required on the project – including clearing and grubbing inside the corridor, access roads, excavations for laying the pipes, constructing water retaining structures as well as buildings for mechanical equipment,” says Henry.

The civil scope along the corridor also included a 51m long steel bridge with concrete piers.  Gabions were constructed in the water crossings and an elevated steel reservoir was constructed in Loeriesfontein next to the water treatment plant to increase pressure in the water network of the municipality, as the pressure from the existing ground-level concrete reservoir was not sufficient.

“The remoteness of the construction areas often meant that a trip from town to site and back could take about four hours, which meant that when you left town in the morning you had to have everything you needed for the day ahead,” says Henry. The logistics, in terms of delivery of materials to site and management of resources, also required precise planning. A 13km long section of the ductile iron underground pipeline was imported and delivered from Cape Town Harbour to a central point on the site. ASLA would then distribute these pipes further along the corridor, and in keeping with the environmental stipulations, all plastic and material hazardous to animals were removed and safely disposed of, off site.

Once the pipeline had been laid, the corridor was rehabilitated using a tractor and a scarifying plough specifically manufactured by ASLA for the contract.

The overall project was completed in July 2018, and the system continues to produce and supply sufficient potable water to Loeriesfontein.

Dignity through infrastructure

Prior to this bulk water supply project, ASLA had undertaken several projects in and around Loeriesfontein, including roads, sewage systems in town, water harvesting facilities, as well as constructing subsidised housing. Residents here are known for their resilience – especially during a very tough five-year drought period – as well as for the pride they take in their town. ASLA employees have always felt welcomed here, often forming firm friendships with the community, that are maintained even after contracts are completed. “It was a very satisfying feeling knowing that we left Loeriesfontein in a better situation than it was before we started working there,” says Henry, “and it is always a good feeling to leave a contract, be it for housing or infrastructure, and know when you leave you have made a difference. I do believe that ASLA, through its projects, has left many communities in a better place.

About Henry Zurnamer

As a young boy, ASLA contracts manager Henry Zurnamer would often build things and had grown up wanting to be involved in building infrastructure. During his first year at Cape Tech, he successfully applied for a bursary at what was then the Department of Water Affairs. After completing his Civil Engineering diploma at Cape Tech in 1988, he worked back his bursary, before joining ASLA in 1992.

During his time as a surveyor for the Department of Water Affairs, Henry gained exposure to larger water infrastructure projects including the Grabow Dam project (Rockview- and Kogelberg dams), and Orange-Riet Canal project in the Free State. Over the past three decades, since joining ASLA, he has worked for both the Civils and Housing divisions, and has worked on countless multi-disciplined projects, within many communities across the Western and Northern Cape. These include some personal project highlights such as a housing project in Delft where he spent six years, and numerous projects in Loeriesfontein since 2011, including the above water infrastructure project during 2017/2018, which occupies a special place in his heart.

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Posted on

July 12, 2024