[1] Univ KwaZulu Natal, Coll Agr Engn & Sci, Sch Life Sci, Private Bag X01, Scottsville, South Africa
[2] Int Water Management Inst, Private Bag X813, ZA-0127 Silverton, South Africa
[3] Western Washington Univ, Inst Environm Toxicol, Bellingham, WA 98225 USA
[4] North West Univ, Water Res Grp Ecol, Unit Environm Sci & Management, Private Bag x6001, ZA-2520 Potchefstroom, South Africa
[5] Inst Nat Resources NPC, POB 100 396, ZA-3209 Scottsville, South Africa
[6] IHE Delft Inst Water Educ, POB 3015, NL-2601 DA Delft, Netherlands
[7] Univ KwaZulu Natal, Coll Agr Engn & Sci, Sch Hydrol, Ctr Water Resources Res, Private Bag X01, Scottsville, South Africa