Technical Abstract: Agricultural productivity in the Southwestern United States depends on irrigation to meet ET needs. Irrigation is required in nine of the ten top agricultural producing counties. Increasing urban demand and drought in the West has resulted in a reduction of water available for maintaining salt balance in irrigated lands. The result of the increased salinity is a reduction of yield and shifting crop patterns. If existing trends continue irrigated agriculture will either require more water to maintain salt balance or new technologies will need to be implemented to maintain current levels of productivity.