Regional water table (1998) and ground-water-level changes in the Mojave River and the Morongo ground-water basins, San Bernardino County, California

U.S. Geological Survey (USGS) | July 1st, 2000

Regional Water Table (1998) and Ground-Water-Level Changes in the Mojave River, and the Morongo Ground-Water Basins, San Bernardino County, California

U.S. Geological Survey (USGS) | July 15th, 2000

The Mojave River and the Morongo groundwater basins are in the southwestern part of the Mojave Desert in southern California. Ground water from these basins supplies a ma

The Mojave River and the Morongo groundwater basins are in the southwestern part of the Mojave Desert in southern California. Ground water from these basins supplies a major part of the water requirements for the region. The rapid and continuous population growth in this area has resulted in ever-increasing demands on local ground-water resources. The continuing collection and interpretation of ground-water data helps local water districts, military bases, and private citizens gain a better understanding of the ground-water systems and, consequently, water availability.

Regional Water Table (2000) and Ground-Water-Level Changes in the Mojave River and the Morongo Ground-Water Basins, Southwestern Mojave Desert, California

U.S. Geological Survey (USGS) | July 1st, 2003

Regional water table (2002) and water-level changes in the Mojave River and the Morongo ground-water basins, Southwestern Mojave Desert, California

U.S. Geological Survey (USGS) | July 1st, 2004

Regional Water Table (2004) and water-level changes in the Mojave River and Morongo ground-water basins, southwestern Mojave Desert, California

U.S. Geological Survey (USGS) | July 1st, 2004

Regional water table (2010) in the Mojave River and Morongo groundwater basins, Southwestern Mojave Desert, California

U.S. Geological Survey (USGS) | February 23rd, 2012

Data for static water-levels measured in about 610 wells during January through June 2010 by the U.S. Geological Survey (USGS), the Mojave Water Agency (MWA), and other l

Data for static water-levels measured in about 610 wells during January through June 2010 by the U.S. Geological Survey (USGS), the Mojave Water Agency (MWA), and other local water districts were compiled to construct a regional water-table map, which shows the altitude of the water table and general direction of groundwater movement in and around the Mojave River and Morongo groundwater basins. Water-level contours from the 2008 water-level map (Stamos and others, 2009) were used as a guide to interpret the 2010 water-level contours in areas where 2010 water-level data were not available. In addition to being available on the interactive map,the 2010 water-level data and contours are shown for the entire area of the Mojave River and Morongo groundwater basins on Plate 1 greater detail of the Warren subbasin in the Morongo groundwater basin is shown on Plate 2. Historical water-level data from the National Water Information System (NWIS) database were used in conjunction with data collected for this study to construct 37 water-level hydrographs to show both long-term (1930 - 2010) and short-term (1990 - 2010) water-level changes in the Mojave River and Morongo groundwater basins. Water-level changes between spring 2008 and spring 2010 were determined by comparing water levels measured in the same well during both periods. Water-level changes between the studies on this website can be displayed on the interactive map by entering the years of interest.

Regional Water Table (2012) in the Mojave River and Morongo Groundwater Basins, Southwestern Mojave Desert, California

U.S. Geological Survey (USGS) | December 31st, 2012

Data for static water-levels measured in about 580 wells during March-May 2012 by the U.S. Geological Survey (USGS), the Mojave Water Agency (MWA), and other local water

Data for static water-levels measured in about 580 wells during March-May 2012 by the U.S. Geological Survey (USGS), the Mojave Water Agency (MWA), and other local water districts were compiled to construct a regional water-table map. This map shows the elevation of the water table and general direction of groundwater movement in and around the Mojave River and Morongo groundwater basins. Water-level measurements recorded by the USGS and MWA staff were compiled according to the procedures described in the Groundwater Technical Procedures of the U.S. Geological Survey (Cunningham and Schalk, 2011). Water-level data submitted by cooperating local water districts were collected by using procedures established by the corresponding agency. All data were compared to historical data for quality-assurance purposes. Water-level contours from the 2010 water-level map (Smith and others, 2011) were used as a guide to interpret the 2012 water-level contours in areas where 2012 water-level data were not available. In addition to being available on the interactive map, 2012 water-level data and contours are shown for the entire area of the Mojave River and Morongo groundwater basins on plate 1; greater detail of the Warren subbasin in the Morongo groundwater basin is shown on plate 2. Water-level data for 2012 are accessible through the website by clicking on the 2012 button above the title on the Water Levels page. Historical water-level data from the National Water Information System (NWIS) database were used in conjunction with data collected for this study to construct 36 water-level hydrographs to show long-term (1930-2012) and short-term (1990-2012) water-level changes in the Mojave River and Morongo groundwater basins. Water-level changes between the spring of 2010 and spring of 2012 were determined by comparing water levels measured in the same well during both periods. Water-level changes between the studies on this website can also be displayed on the interactive map by selecting the years of interest from the Groundwater Data menu.

Regional water table (2014) in the Mojave River and Morongo Groundwater Basins, southwestern Mojave Desert, California

U.S. Geological Survey (USGS) | June 28th, 2016

Data for static water-levels measured in about 610 wells during March-April 2014 by the U.S. Geological Survey (USGS), the Mojave Water Agency (MWA), and other local wate

Data for static water-levels measured in about 610 wells during March-April 2014 by the U.S. Geological Survey (USGS), the Mojave Water Agency (MWA), and other local water districts were compiled to construct a regional water-table map. This map shows the elevation of the water table and general direction of groundwater movement in and around the Mojave River and Morongo groundwater basins. Water-level measurements recorded by the USGS and MWA staff were measured and compiled according to the procedures described in the Groundwater Technical Procedures of the U.S. Geological Survey (Cunningham and Schalk, 2011). Water-level data submitted by cooperating local water districts were collected by using procedures established by the corresponding agency, and compiled according to the procedures described in the Groundwater Technical Procedures of the U.S. Geological Survey (Cunningham and Schalk, 2011). All data were compared to historical data for quality-assurance purposes. Water-level contours from the 2012 water-level map (Teague and others, 2014) were used as a guide to interpret and shape the 2014 water-level contours in areas where 2014 water-level data were not available; these contours are shown as dashed (approximate) on the water-table map. In addition to being available on the interactive map, 2014 water-level data and contours are shown for the entire area of the Mojave River and Morongo groundwater basins on Plate 1. Water-level data for 2014 are accesible through the website by clicking the 2014 Sites button on the Data Downloads page.

Regional Water Table (2016) in the Mojave River and Morongo Groundwater Basins, Southwestern Mojave Desert, California

U.S. Geological Survey (USGS) | December 27th, 2017

Data for static groundwater-levels measured in about 645 wells during the period of January-April 2016 by the United States Geological Survey (USGS), the Mojave Water Age

Data for static groundwater-levels measured in about 645 wells during the period of January-April 2016 by the United States Geological Survey (USGS), the Mojave Water Agency, and other local water districts were compiled to construct a regional water-table map. The downloadable shapefile shows the elevation of the water table in the Mojave River and Morongo groundwater basins. This dataset is a digital representation of the contours presented on Plate 1 of Regional Water Table (2016) in the Mojave River and Morongo Groundwater Basins, Southwestern Mojave Desert, California: U.S. Geological Survey Scientific Investigation Map, doi:10.5066/sim3391, published by Meghan C. Dick and Adam R. Kjos. It is a continuation of a study first published in 2007. The initial version of the Scientific Investigations Report (SIR) includes data for 1992 to 2008 (SIR 2007-5097). This data release also serves as a repository for a selection of tabular data used in the 2016 Mojave River and Morongo groundwater basin regional water table map. The data represent water level measurements provided by cooperating water agencies whose data collection standards may not meet the criteria set forth by the U.S. Geological Survey for inclusion in the USGS National Water Information System (NWIS).

Relative risk of groundwater-quality degradation near California (USA) oil fields estimated from 3H, 14C, and 4He

Applied Geochemistry (Elsevier) | June 5th, 2021

 Relative risks of groundwater-quality degradation near selected California oil fields are estimated by examining spatial and temporal patterns in chemical and isotopic

 Relative risks of groundwater-quality degradation near selected California oil fields are estimated by examining spatial and temporal patterns in chemical and isotopic data in the context of groundwater-age categories defined by tritium and carbon-14. In the Coastal basins, western San Joaquin Valley (SJV), and eastern SJV; 82, 76, and 0% of samples are premodern (pre-1953 recharge), respectively; and 3, 0, and 31% are modern (recharged during or after 1953), respectively. Carbon-14 and helium-4 data indicate most premodern samples are 1000 to 10,000 (33%) or >10,000 (50%) years old. Organic chemicals that could be associated with deeper hydrocarbon reservoirs (e.g. thermogenic gases and benzene) occur most frequently in premodern groundwater, suggesting premodern groundwater has a higher risk of degradation from upward migration of hydrocarbons than modern and mixed-age groundwater. Low sulfate concentrations in some premodern groundwater containing high thermogenic-methane concentrations (>28 mg/L) indicate methane attenuation associated with sulfate reduction can be limited in premodern groundwater. The more common occurrence of manufactured compounds, like tetrachloroethene, in modern and mixed-age groundwater than in premodern groundwater indicates modern and mixed-age groundwater has a higher risk of degradation from land-surface sources than premodern groundwater. Time-series data for chloride in groundwater affected by disposal of oil-field water in unlined ponds indicate some modern and mixed-age groundwater are susceptible to chemical migration within 2–3 km of surface sources. Timescales for diluting chloride concentrations in groundwater with fresh recharge once disposal ponds are decommissioned are shorter in mixed-age groundwater with large fractions of modern water (9–14 years in one example) than in mixed-age groundwater with large fractions of premodern water (no evidence of dilution after 12 years of monitoring in one example). The presence of predominantly premodern groundwater in the Coastal basins and western SJV indicates these areas have relatively high risk from upward migration of hydrocarbons, reduced methane attenuation capacity, and long dilution times, whereas predominantly modern-and mixed-age groundwater in the eastern SJV indicates this area has relatively high risk from chemical migration from land-surface sources and subsequent extensive spreading. Age-based characterizations of relative risk could inform the design of groundwater-monitoring programs near oil fields in terms of the spatial distribution of monitoring points relative to source areas and monitoring frequency and duration.