[1] Cape Peninsula Univ Technol, Dept Environm & Occupat Studies, POB 652, ZA-8000 Cape Town, South Africa
[2] Cape Peninsula Univ Technol, Ctr Water & Sanitat Res, Dept Civil Engn, ZA-7535 Bellville, Western Cape, South Africa
[3] ARC Infruitec Nietvoorbij, Private Bag X5026, ZA-7599 Stellenbosch, South Africa
[4] Cape Peninsula Univ Technol, Dept Agr, ZA-7655 Wellington, Western Cape, South Africa