Pacific Southwest Water Yield and Environmental Quality Improvement Act

Pacific Southwest Water Yeild and Environmental Quality Improvement Act - Authorizes the Secretary of Agriculture (with respect to lands administered by the Department of Agriculture) or the Secretary of the Interior (with respect to lands administered by the Department of the Interior) to survey, evaluate, implement, and allocate funds for plans for water yield improvement practices on public and private lands in Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming.

Sets forth the conditions for receipt of Federal assistance for the implementation of water yield improvement practices, including obtaining agreements from permittees and lessees (on public lands) or owners (of private lands), the aggregate of which constitutes at least 50 percent of the area in the watershed in which the approved practices are to be performed.

Authorizes appropriations as necessary, not to exceed $150,000,000, excluding administrative costs, to carry out the provisions of this Act.