The Esther Park WCW is situated in Kempton Park, in the DD3 drainage district. It is the smallest of ERWAT’s 19 wastewater care works with an original capacity of 0,4 Mℓ/d. It was built in 1979 and is situated adjacent to the Esther Park residential area. This conventional activated sludge process was initially designed for only carbon and nitrogen reduction and therefore requires chemical addition for phosphate removal. The plant was upgraded to 1.0 ML/day by the addition of one final settling tank in 2013. Treated effluent flows into the Modderspruit and eventually into the Jukskei River drainage district in quaternary catchment A21C.