IWA has its roots in the International Water Supply Association (IWSA), established in 1947, and the International Association on Water Quality (IAWQ), which originally formed as the International Association for Water Pollution Research in 1965.
IWA har sina rötter i International Water Supply Association (IWSA), som bildades 1947, och International Water Quality Association (IAWQ), som ursprungligen bildades 1965 under namnet International Association for Water Pollution Research.