Preliminary Evaluation of the Hydrogeologic System in Owens Valley, California

U.S. Geological Survey (USGS) | January 8th, 1988

Owens Valley is a major source of water for southern California and presently (1986) provides more than 60 percent of the supply for Los Angeles. Since 1970, ground-water

Owens Valley is a major source of water for southern California and presently (1986) provides more than 60 percent of the supply for Los Angeles. Since 1970, ground-water withdrawal from Owens Valley has increased, and a decline in the health of vegetation has been reported. In 1982, a cooperative project to study the hydrogeology and plant ecology of Owens Valley was begun by Inyo County, the Los Angeles Department of Water and Power, and the U.S. Geological Survey. As part of this project, the available data and present hydrologic concepts of Owens Valley were evaluated by using a ground-waterflow model. Results of this preliminary evaluation are being used to guide data collection and the development of more sophisticated hydrologic models.

Preliminary hydrogeologic assessment near the boundary of the Antelope Valley and El Mirage Valley groundwater basins, California

U.S. Geological Survey (USGS) | July 19th, 2017

Preliminary update of DWR evaluation of San Joaquin Valley - Kern County basin Groundwater Sustainability Plan (GSP)

California Department of Water Resources (DWR) | December 9th, 2021

Probabilistic Subsidence Forecast Model for the California Aqueduct Subsidence Program, San Joaquin Valley, California: Revision 1 Design Report

California Department of Water Resources (DWR) | October 4th, 2024

This report documents the development of a probabilistic subsidence forecast model for simulating a plausible range of future land-surface altitude conditions along the C

This report documents the development of a probabilistic subsidence forecast model for simulating a plausible range of future land-surface altitude conditions along the California Aqueduct (Aqueduct) and San Luis Canal in the San Joaquin Valley (SJV), with an emphasis on areas of localized subsidence (i.e., “subsidence bowls”). The model forecasts will be used to inform long-term planning and on-going analyses of potential investments needed to provide a suitable level of performance for the Aqueduct. The forecast model is primarily based on an empirical relationship between historical subsidence rates and annual water deliveries from the Central Valley Project (CVP) and State Water Project (SWP). A key assumption of the model is that the rate of groundwater overdraft, which contributes to loss of aquifer storage and permanent land subsidence, is correlated with CVP and SWP deliveries, and specifically with higher groundwater storage loss during severe drought years. Another key assumption is that the same rates of subsidence will continue even after groundwater levels decline and extraction may be coming from deeper parts of the aquifer system. If the geology and/or aquifer properties change dramatically in response, then these new conditions may have an unmodeled impact on future rates. 

Progress Report: Subsidence in California, March 2015 – September 2016

Jet Propulsion Laboratory (JPL) | February 7th, 2017

Subsidence caused by groundwater pumping in the Central Valley has been a problem for decades. Over the last few years, interferometric synthetic aperture radar (InSAR) h

Subsidence caused by groundwater pumping in the Central Valley has been a problem for decades. Over the last few years, interferometric synthetic aperture radar (InSAR) has been used from satellites and aircraft to produce maps of subsidence with sensitivity of fractions of an inch. For this study, we have obtained and analyzed data from the European Space Agency’s satellite-borne Sentinel-1A from the period March 2015 – September 2016 and the NASA airborne UAVSAR for the period March 2015 – June 2016, and produced maps of total subsidence from the two data sets. These data add to the earlier data processed from the Japanese PALSAR for 2006 – 2010, Canadian Radarsat-2 for the period May 2014 – January 2015, and UAVSAR for July 2013 - March 2015, for which subsidence measurements were reported previously (Farr et al., 2015). Here we also present results for the South-Central coast of California including Ventura, Oxnard, Santa Barbara and north to the San Joaquin Valley as well as the Santa Clara Valley from colleagues who have processed Sentinel-1A data covering March 2015 – March 2016. As multiple scenes were acquired during these periods, we can also produce time histories of subsidence at selected locations and transects showing how subsidence varies both spatially and temporally.

Projecting groundwater storage changes in California’s Central Valley

Nature Portfolio (Springer Nature) | August 27th, 2018

Accurate and detailed knowledge of California’s groundwater is of paramount importance for statewide water resources planning and management, and to sustain a

Accurate and detailed knowledge of California’s groundwater is of paramount importance for statewide water resources planning and management, and to sustain a multi-billion-dollar agriculture industry during prolonged droughts. In this study, we use water supply and demand information from California’s Department of Water Resources to develop an aggregate groundwater storage model for California’s Central Valley. The model is evaluated against 34 years of historic estimates of changes in groundwater storage derived from the United States Geological Survey’s Central Valley Hydrologic Model (USGS CVHM) and NASA’s Gravity Recovery and Climate Experiment (NASA GRACE) satellites. The calibrated model is then applied to predict future changes in groundwater storage for the years 2015–2050 under various precipitation scenarios from downscaled climate projections. We also discuss and project potential management strategies across different annual supply and demand variables and how they affect changes in groundwater storage. All simulations support the need for collective statewide management intervention to prevent continued depletion of groundwater availability.

Pumping and Ground-Water Storage Depletion in Las Vegas Valley, Nevada, 1955-1974

U.S. Geological Survey (USGS) | July 1st, 1976

Quantification of record-breaking subsidence in California’s San Joaquin Valley

Nature Portfolio (Springer Nature) | November 19th, 2024

Rapid groundwater decline and some cases of recovery in aquifers globally

Nature Portfolio (Springer Nature) | January 24th, 2024

Recommendations to Address the Expansion of Seawater Intrusion in the Salinas Valley Groundwater Basin

Monterey County Water Resources Agency (MCWRA) | October 12th, 2017

This report provides a discussion of the current knowledge and related background information surrounding seawater intrusion pathways and potential impacts ther

This report provides a discussion of the current knowledge and related background information surrounding seawater intrusion pathways and potential impacts thereof on the Salinas Valley Groundwater Basin. This document also serves as a body of evidence to catalogue the findings used to support the recommendations presented herein. Staff is making six recommendations, with each focused on a component that influences, or could be impacted by, the advancement of seawater intrusion. The recommendations are being presented in an order that builds upon the foundational knowledge laid out in the background section of this report, rather than in an order of priority. Each recommendation can be implemented on its own or in concert with the others, and the relative importance of each will be discussed individually in this report. However, the recommendations have been conceptualized as a comprehensive solution that, along with continued operation of projects that have been constructed for the same purpose, have the strongest potential to ensure success in slowing or halting further seawater intrusion when implemented simultaneously.