Water Quality of Groundwater Used for Public Supply in Principal Aquifers of the Western United States

U.S. Geological Survey (USGS) | September 8th, 2020

Water shortage risks from perennial crop expansion in California's Central Valley

Environmental Research Letters (IOP) | October 15th, 2019

California's Central Valley is one of the world's most productive agricultural regions. Its high-value fruit, vegetable, and nut crops rely on surface water imports from

California's Central Valley is one of the world's most productive agricultural regions. Its high-value fruit, vegetable, and nut crops rely on surface water imports from a vast network of reservoirs and canals as well as groundwater, which has been substantially overdrafted to support irrigation. The region has undergone a shift to perennial (tree and vine) crops in recent decades, which has increased water demand amid a series of severe droughts and emerging regulations on groundwater pumping. This study quantifies the expansion of perennial crops in the Tulare Lake Basin, the southern region of the Central Valley with limited natural water availability. A gridded crop type dataset is compiled on a 1 mi2 spatial resolution from a historical database of pesticide permits over the period 1974–2016 and validated against aggregated county-level data. This spatial dataset is then analyzed by irrigation district, the primary spatial scale at which surface water supplies are determined, to identify trends in planting decisions and agricultural water demand over time. Perennial crop acreage has nearly tripled over this period, and currently accounts for roughly 60% of planted area and 80% of annual revenue. These trends show little relationship with water availability and have been driven primarily by market demand. From this data, we focus on the increasing minimum irrigation needs each year to sustain perennial crops. Results indicate that under a range of plausible future regulations on groundwater pumping ranging from 10% to 50%, water supplies may fail to consistently meet demands, increasing losses by up to 30% of annual revenues. More broadly, the datasets developed in this work will support the development of dynamic models of the integrated water-agriculture system under uncertain climate and regulatory changes to understand the combined impacts of water supply shortages and intensifying irrigation demand.

Water Stress and a Changing San Joaquin Valley

Public Policy Institute of California (PPIC) | March 1st, 2017

The San Joaquin Valley—California’s largest agricultural region, and an important contributor to the nation’s food supply—is in a time of great change and growing

The San Joaquin Valley—California’s largest agricultural region, and an important contributor to the nation’s food supply—is in a time of great change and growing water stress. Agriculture is a leading economic driver and the predominant water user. The region’s farms and related manufacturing businesses account for 25 percent of the valley’s revenues and 16 percent of local jobs—and 89 percent of annual net water use. The latest drought underscored valley agriculture’s vulnerability to water scarcity and long-term declines in groundwater reserves. The region has a greater abundance of productive farmland than local water supplies for irrigation. In most years since the mid-1980s, groundwater has been used faster than it is being replenished (“groundwater overdraft”). Over the past three decades, overdraft has averaged nearly 2 million acre-feet per year, or 13 percent of net water use. This has contributed to increased pumping costs, dry wells, sinking lands, and declining reliability of this vital drought reserve.

Water Supply Conditions in Southern California during 1958-1959, Volume II, Water Level Data, Central Coastal and Los Angeles Regions

California Department of Water Resources (DWR) | May 1st, 1961

Water Year 2017: What a Difference a Year Makes

California Department of Water Resources (DWR) | October 3rd, 2022

The very wet conditions of 2017 gave many parts of the state access to excess surface waters for both planned and impromptu groundwater recharge, and fall 2017 groundwate

The very wet conditions of 2017 gave many parts of the state access to excess surface waters for both planned and impromptu groundwater recharge, and fall 2017 groundwater level data (not available until the end of the calendar year) should show the effects of the substantial recharge water available

Water-Level and land-subsidence studies in the Mojave River and Morongo groundwater basins; 2007

U.S. Geological Survey (USGS) | June 25th, 2007

Since 1992, the U.S. Geological Survey (USGS), in cooperation with the Mojave Water Agency (MWA), has constructed a series of regional water-table maps for intermittent y

Since 1992, the U.S. Geological Survey (USGS), in cooperation with the Mojave Water Agency (MWA), has constructed a series of regional water-table maps for intermittent years in a continuing effort to monitor groundwater conditions in the Mojave River and Morongo groundwater basins. The previously published data, which were used to construct these maps, can be accessed on the interactive map. The associated reports describing the groundwater conditions for the Mojave River groundwater basin for 1992 (Stamos and Predmore, 1995), the Morongo groundwater basin for 1994 (Trayler and Koczot, 1995), and for both groundwater basins for 1996 (Mendez and Christensen, 1997); for 1998 (Smith and Pimentel, 2000), for 2000 (Smith, 2002), for 2002 (Smith and others, 2004), for 2004 (Stamos and others, 2004), and for 2006 (Stamos and others, 2007) can be accessed using this web site.

Water-Resources Data for the Devils Hole Area, Nye County, Nevada, July 1978 - September 1988

U.S. Geological Survey (USGS) | July 1st, 1993

Data on water levels, spring discharge, and consumption of electric power by irrigation pumps collected at Devils Hole and vicinity from July 1978 through September 1988

Data on water levels, spring discharge, and consumption of electric power by irrigation pumps collected at Devils Hole and vicinity from July 1978 through September 1988 are reported herein. These data were collected to document the effects of irrigation pumping on the pool level at Devils Hole and the recovery following cessation of irrigation pumping in August 1982. The pool contains the endangered species of pupfish, Cyprinodon diabolis. Data on fluctuations in water level and springflow are presented in graphic form. Data on consumption of electric power by pumps in irrigation wells, useful as an index of the pumpage, are presented in tabular form.

We Don't Do Groundwater: A Morsel of California Legal History

Berkeley Law Scholarship Repository | January 1st, 2002

It must seem surprising to people elsewhere that California, unlike other western states, continues to treat surface water and groundwater under separate and distinct leg

It must seem surprising to people elsewhere that California, unlike other western states, continues to treat surface water and groundwater under separate and distinct legal regimes, even though everyone today acknowledges that water comprises a continuum through which the water moves wherever gravity takes it.  Moreover, whatever "mystery" there once was about the movement of water underground, and that induced lawmakers and treatise writers to eschew efforts to regulate groundwater, is no longer a hindrance to modern management, as most states have acknowledged. What, then, explains California's failure to bring its water law into line with contemporary knowledge, and with scientific reality? The answer (actually there are two answers) is not very mysterious.

Wells of Southern California

Scientific American | March 22nd, 1902

In the Series of Water Supply Irrigation Papers, the United States Geological Survey has in press, but not yet published, the “Wells of Southern California" (Nos. 59

In the Series of Water Supply Irrigation Papers, the United States Geological Survey has in press, but not yet published, the “Wells of Southern California" (Nos. 59 and 60), by Mr. Joseph Barlow Lippincott. In his letter of transmittal Mr. F.H. Newell, Hydrographer in Charge, remarks: "The results are instructive, as showing what may be done in other parts of the United States under favorable conditions of climate and soil, and have peculiar interest in any consideration of the extent to which the arid land can ultimately be redeemed by irrigation." The region discussed is the San Bernardino Valley in Southern California, which has an area of 563 square miles, and lies south and west of the Sierra Madre and San Bernardino Mountains. Riverside and Rcdlands are the centers of fruit production. Up to elevations of 2,000 feet the relatively high lands are free from frost, and the relatively low lands are subject to it. The distinctive crop of San Barnardino Valley is citrus fruits. Oranges predominate, followed next by lemons, and of late years the grape fruit has become a popular product. Olives, almonds, prunes, apricots, peaches, pears, and wine, raisin, and table grapes, are all grown to perfection in this district. In the eleven years prior to 1898 Riverside shipped nearly seven million boxes of oranges, an average annual income of $1,000,000. Water is the lifeblood of the land.

Westside Subbasin Groundwater Sustainability Plan

Westlands Water District | January 23rd, 2020