In cooperation with MWA, the U.S. Geological Survey (USGS) has conducted a series of regional water level and land-subsidence studies in the Mojave River and Morongo Groundwater Basins. This on-going scientific investigation, which began in 1992, is an effort to monitor groundwater conditions of the southwestern part of the Mojave Desert. For further information and other map documents please access the USGS site: Mojave Water Resources