The major dams in the area are Buffelspoort, Haartbeespoort, Klein Marico, Krommellenboog, Marico Bosveld and the Molatedi dams. The location of the province implies that it has short rivers with minimum dilution effect, with the return flows impacting on the two major river systems, namely the Vaal and Crocodile (West). The main sources of water pollution are: . Urban / Industrial effluent return flows . Mining effluents and dewatering . Diffuse sources of pollution . Non compliance of sewerage works due to lack of finances and human resources . Eutrophication . Agricultural waste (nitrates)