Subsurface Agricultural Drainage in California’s San Joaquin Valley

This chapter focuses on drainage from California&s;s San Joaquin Valley; however, the material on environmental concerns and salt balance is relevant to other areas of the world where similar problems exist. The most common solution to the drainage problem on the west side has been to install artificial drains at field depths of 2 to 3 m. The drainage goes to a confined natural salt sink, the Salton Sea, which for years has sustained California&s;s most productive inland fishery. Exact quantities of drainage from the San Joaquin Valley are difficult to estimate. California&s;s Mediterranean climate results in winter rains and hot, dry summers. The California Department of Fish and Game and the US Fish and Wildlife Service participated in the program and endorsed the recommended plan. Farmers in the west side of the San Joaquin Valley apply over 150 organic chemicals to soils and crops for pest control.