In the Mangaung district, south of Bloemfontein, lies the large community of Botshabelo whose water is supplied from the Botshabelo Reservoir. It was recently discovered that approximately 8000 litres of water a month were being lost through faulty joints in the reservoir. To repair and reseal these joints, Sika’s renowned Sikadur-Combiflex SG system was specified for the project. Engineering company, Bigen Africa awarded the contract to Kitso Trading, part of the AAS Group whose motto is ‘Cleaner water for a better future’.

Prior to commencement of the project in June 2012, Mangaung Local Municipality emptied the reservoir, and contractors were then under pressure to complete the work timeously so as not to inconvenience the Botshabelo community. The extremely poor condition of the reservoir joints called for sandblasting of the surface area to remove all grit and contamination. The joints were then coated with a layer of Sikadur-31 CF Normal; as part of the Sikadur-Combiflex SG system, this two-part, moisture-tolerant, thixotropic adhesive and repair mortar is based on a combination of epoxy resins and special fillers. A high strength adhesive, it is easy to mix and apply, hardens without shrinkage and is impermeable to liquids and water vapour.

The second product in this highly versatile system is Sikadur-Combiflex SG tape, which was rolled out over the epoxy layer. It consists of a modified flexible polyolefin (FPO) waterproofing tape with advanced adhesion that is used for expansion, construction and connection joints as well as for cracks. When fixed to the joint, Sikadur-Combiflex SG tape allows for irregular and high movement in more than one direction whilst still maintaining a high quality seal. Weather and water resistant and easy to install, it performs well within a wide temperature range and provides excellent adhesion to many materials. It is supplied in various sizes, and on this project 425metres of 250mm x 2mm tape and 125 metres of 300mm x 2mm tape were applied to the reservoir joints. A final layer of Sikadur-31 CF Normal (in total 52 x 15litres) was then applied over the Combiflex tape resulting in an almost seamless application.

As predicted, no leaks were detected once the reservoir was refilled. With its international approval for contact with drinking water, the versatile Sikadur-Combiflex SG system once again proved its outstanding quality and Mangaung Local Municipality is guaranteed that well into the foreseeable future, Botshabelo Reservoir will be supplying water to the local community.