From January to April 2016,the U.
S. Geological Survey (USGS), the Mojave Water Agency, and other local water districts made approximately 1200 water-level measurements in about 645 wells located within 15 separate groundwater basins,collectively referred to as the Mojave River and Morongo groundwater basins. These data document recent conditions and, when compared with older data, and changes in groundwater levels. A water-level contour map was drawn using data measured in 2016 that shows the elevation of the water table and general direction of groundwater movement for most of the groundwater basins. Historical water-level data stored in the USGS National Water Information System (https://waterdata.usgs.gov/nwis/) database were used in conjunction with data collected for this study to construct 37 hydrographs to demonstrate long-term (1930–2016) and short-term (1990–2016) water-level changes in the study area.
Source: usgs.gov