WISA was formed in 1987 when the Southern African branch of the Institute of Water Pollution Control, originally founded in 1937, was disbanded. At the beginning of 2000 WISA was incorporated as an association not for gain. This means that WISA shall use its funds and assets solely to further its stated aims and objectives and no funds or assets shall be distributed to any other person or body. The institute currently consists of 3,162 members including individuals, various government institutions and private organisations. WISA aims to promote professional excellence in the water sector through sharing knowledge, building expertise and improving quality of life.