Civil Engineering June 2021 | Vol 29 No 5

The comprehensive contract was awarded to ASLA Construction at a total value of R101 120 688,83. The project was success- fully completed in July 2018. Since mid- May 2018 the system has been producing sufficient water of acceptable quality for the town of Loeriesfontein. The groundwater levels of all the boreholes are managed continuously and abstraction rates are managed accordingly. Both the engineer and the hydrogeologists monitor this system’s data on a three-monthly basis and advise the Hantam Municipality on allowable abstraction. The following contractors were em- ployed on this contract: Q Q Civil works and lead contractor: ASLA Construction Q Q Mechanical works: Hidro-Tech Systems Q Q Electrical control & instrumentation: Woodrow Engineering Q Q Electrical: MV powerlines & trans- formers: EMC Reticulation Q Q Telemetry system: Spectrum Communications Q Q Engineer: BVi Consulting Engineers Q Q Hydrogeologists: GEOSS South Africa Q Q Environmental assessment & control: EnviroAfrica Q Q Project financing: Department of Water and Sanitation THE BRANDVLEI PROJECT The village of Brandvlei is located on the R27 between Calvinia and Kenhardt. Brandvlei has a population of 2 580 people and is totally dependent on groundwater for its water supply. The town’s annual average rainfall of 89 mm per annum and an evaporation rate of 2 800 mm per annum classifies the area as arid. Brandvlei is located on the bank of the Sak River, which originates in the Nuweveld Mountains near Beaufort West, some 500 km away. This area of the Karoo is famous for its pans or “vloere” as they are known locally – Verneuk Pan and Grootvloer Pan being the largest of these. During periods of high rainfall, these pans fill up and serve to connect the Sak River system with the Orange River via the Hartbees River. Brandvlei’s borehole field has a recharge system which has been opera- tional since the 1960s. The town’s well- field is located 50 km south of Brandvlei on the farm Romanskolk. An earth embankment was constructed across the Romanskolk Pan, which serves to impound runoff from rainfall in the area. The impounded water then recharges the aquifer below. There are six boreholes drilled on the perimeter of the Romanskolk pan, from where water is abstracted from the aquifer. With drought conditions occur- ring the past seven years, there was no recharge and the aquifer was subsequently emptied. The Department of Water and Sanitation provided drought relief funding in 2018, and an exploration drilling pro- ject was initiated during which a further 30 boreholes were drilled in areas around Brandvlei. What commonly happens in this area is that when sufficient volumes of water are found, the water quality is very poor, and when fresh water is found, the yields are very low. Nonetheless, a further seven boreholes were identified as possible production units. A feasibility study was conducted and the project was approved for implementation by the Department Water and Sanitation in September 2018. The project comprised the following scope of works: Q Q Development and equipping of seven new boreholes at Romanskolk, com- plete with switchgear, instrumentation and security cages Q Q Replacement of pumps, switchgear, instrumentation, and security cages at six existing boreholes at Romanskolk 32 June 2021 Civil Engineering Figure 5 Construction of the Brandvlei Gravity Main Figure 4 Loeriesfontein Water Treatment Plant