Water quality coalitions have been formed throughout the Central Valley in response to Conditional Waiver of Waste Discharge Requirements passed in 2003. The Central Valley Regional Water Quality Control Board (Regional Board) administers the regulatory program, which has been modified since its inception and is currently named the Irrigated Lands Regulatory Program (ILRP).

Viewed by many as the most economical way to comply with the regulations, the coalitions' goal is to represent farmers with irrigated cropland within a regional watershed so they don't need to maintain individual discharge permits with the Regional Board.

The coalitions conduct monthly and seasonal surface-water water quality monitoring and water and sediment toxicity analyses. Results are reported to the Regional Board on a quarterly basis. The occurrence of two or more exceedances of Basin Plan water quality and/or toxicity parameters results in the mandatory production of a management plan to address the issues.

In addition, data on crops, irrigation types and scheduling, management practices implemented to protect water quality, fertilizer use, and other data are collected by coalitions through grower surveys, and reported to the Regional Board. Coalitions are also responsible for providing educational materials and outreach opportunities for growers.

Coalitions are listed below from north to south: