The Exchange Contractors Water Authority services approximately 240,000 acres of prime agricultural land east of I-5 and primarily west of the San Joaquin River. These lands span the counties of Fresno, Madera, Merced, and Stanislaus, from the town of Patterson in the north to Mendota in the south. The Exchange Contractors mission is to monitor environmental, legislative, and legal issues which impact the Exchange Contractors members and to defend the Exchange Contractors water rights.