Fish & Wildlife Groundwater Planning Considerations: Freshwater Wetlands

California Department of Fish and Wildlife (CDFW) | June 6th, 2019

 In 2014, California passed the Sustainable Groundwater Management Act (SGMA) (AB1739, SB 1168, SB 1319), authorizing local groundwater sustainability agencies to develo

 In 2014, California passed the Sustainable Groundwater Management Act (SGMA) (AB1739, SB 1168, SB 1319), authorizing local groundwater sustainability agencies to develop groundwater sustainably plans for a subset of California’s alluvial aquifers. This document provides considerations to assist local groundwater sustainability agencies in avoiding or minimizing adverse impacts to freshwater wetland beneficial uses and users of groundwater in local groundwater management planning and implementation. The information provided is intended to help local groundwater planners, groundwater planning proponents and consultants, and California Department of Fish and Wildlife (CDFW) staff work together to protect wetlands as a public trust resource. 

Five-century record of climate and groundwater recharge variability in southern California

Nature Portfolio (Springer Nature) | December 3rd, 2019

Modifications to the rates of water flowing from the surface to groundwater (groundwater recharge) due to climate variability are the most difficult to assess because of

Modifications to the rates of water flowing from the surface to groundwater (groundwater recharge) due to climate variability are the most difficult to assess because of the lack of direct long-term observations. Here, we analyze the chloride salt distribution below the surface soil on a plateau near Los Angeles to reconstruct the amount of recharge that occurred in the last five centuries. Over this time interval, periods of major high and low recharge with different duration follow each other and this cyclicity is consistent with long-term atmospheric forcing patterns, such as the Pacific Decadal Oscillation. This study determines the range and the natural variability of recharge to groundwater, which sustains local freshwater flow system, and helps forecast future availability of groundwater resource in southern California, where water scarcity is critical to both local and global populations.

FLOOD- MAR Using Flood Water for Managed Aquifer Recharge to Support Sustainable Water Resources

California Department of Water Resources (DWR) | June 26th, 2018

The effects of climate change are necessitating wholesale changes in how water is managed in California.  With less water storage from snowpack, California needs to leve

The effects of climate change are necessitating wholesale changes in how water is managed in California.  With less water storage from snowpack, California needs to leverage both the current water system and new opportunities to provide sustainable alternatives that can simultaneously accommodate longer and deeper droughts, and more severe, and frequent, episodic and seasonal flooding. This recent cycle of drought and flood, and the passage of the Sustainable Groundwater Management Act (SGMA), provide an enhanced opportunity to modernize State policies related to the nexus between flood management, land use, groundwater management, and ecosystem enhancement. Partnerships, among DWR; other State, federal, tribal, regional, and local entities; and university and private researchers, are actively exploring opportunities to determine how flood and groundwater management can be integrated for multiple benefits. Although integrating flood and groundwater management is not a new concept, the time is ripe to implement an expanded, large-scale integrated program. With the passage and early implementation of SGMA, in combination with climate-induced extreme events, the logic for communities to partner and integrate is evident and imperative. This partnership will help reduce the impacts of future swings between high- and low-flow periods while meeting their communities’ objectives, with the added benefits of improving floodplain ecosystems, preserving working landscapes, and engaging California’s agricultural community in needed solutions, among others. This white paper explores “Flood-MAR”, an integrated and voluntary resource management strategy that uses flood water resulting from, or in anticipation of, rainfall or snowmelt for groundwater recharge on agricultural lands and working landscapes, including but not limited to refuges, floodplains, and flood bypasses. Large-scale implementation of Flood-MAR will fundamentally change how flood and groundwater management are managed. Flood-MAR can be implemented at multiple scales, from individual landowners diverting flood water with existing infrastructure, to using extensive detention/recharge areas and modernizing flood protection infrastructure/operations. Flood-MAR’s potential and value for California is achieved by integrating Flood-MAR with other regional recharge efforts, changing management of California’s water system to better integrate surface water and groundwater, upgrading conveyance, storage, and operations, and considering Flood-MAR’s opportunities as related to water transport and transfers are some of the system integration considerations. This white paper demonstrates the need for Flood-MAR to become an important part of California’s portfolio of water resource management strategies, now and in the future, to help significantly improve water resources sustainability and climate resiliency throughout the state.  Using Flood Water for Managed Aquifer Recharge Can Provide Broad Benefits. There is a clear State interest in encouraging, and participating in, Flood-MAR projects because they can provide broad and multiple public and private benefits for Californians and the ecosystems of the state. Potential public benefits include: - Flood Risk Reduction. - Drought Preparedness. - Aquifer Replenishment. - Ecosystem Enhancement. - Subsidence Mitigation. - Water Quality Improvement. - Working Landscape Preservation and Stewardship.

Flood-MAR Research and Data Development Plan

California Department of Water Resources (DWR) | October 31st, 2019

The Research Advisory Committee (RAC) is pleased to make this plan available to the growing network of farmers, researchers, planners, and water and land managers who wan

The Research Advisory Committee (RAC) is pleased to make this plan available to the growing network of farmers, researchers, planners, and water and land managers who want to expand our collective knowledge about using floodwaters for managed aquifer recharge (Flood-MAR). This plan outlines the priority information needed by those making management decisions about the where, when, and how of capturing available flood water to replenish California’s depleted aquifers.

Fluid migration pathways to groundwater in mature oil fields: Exploring the roles of water injection/production and oil-well integrity in California, USA

Science of The Total Environment (Elsevier) | August 23rd, 2023

Focused groundwater recharge in the Amargosa Desert basin

U.S. Geological Survey (USGS) | July 1st, 2007

 The Amargosa River is an approximately 300-kilometer-long regional drainage connecting the northern highlands on the Nevada Test Site in Nye County, Nev., to the floor

 The Amargosa River is an approximately 300-kilometer-long regional drainage connecting the northern highlands on the Nevada Test Site in Nye County, Nev., to the floor of Death Valley in Inyo County, Calif. Streamflow analysis indicates that the Amargosa Desert portion of the river is dry more than 98 percent of the time. Infiltration losses during ephemeral flows of the Amargosa River and Fortymile Wash provide the main sources of ground-water recharge on the desert-basin floor. The primary use of ground water is for irrigated agriculture. The current study examined ground-water recharge from ephemeral flows in the Amargosa River by using streamflow data and environmental tracers. The USGS streamflow-gaging station at Beatty, Nev., provided high-frequency data on base flow and storm runoff entering the basin during water years 1998–2001. Discharge into the basin during the four-year period totaled 3.03 million cubic meters, three quarters of which was base flow. Streambed temperature anomalies indicated the distribution of ephemeral flows and infiltration losses within the basin. Major storms that produced regional flow during the four-year period occurred in February 1998, during a strong El Niño that more than doubled annual precipitation, and in July 1999. The study also quantified recharge beneath undisturbed native vegetation and irrigation return flow beneath irrigated fields. Vertical profiles of water potential and environmental tracers in the unsaturated zone provided estimates of recharge beneath the river channel (0.04–0.09 meter per year) and irrigated fields (0.1–0.5 meter per year). Chloride mass-balance estimates indicate that 12–15 percent of channel infiltration becomes ground-water recharge, together with 9–22 percent of infiltrated irrigation. Profiles of potential and chloride beneath the dominant desert-shrub vegetation suggest that ground-water recharge has been negligible throughout most of the basin since at least the early Holocene. Surface-based electrical-resistivity imaging provided areal extension of borehole information from sampled profiles. These images indicate narrowly focused recharge beneath the Amargosa River channel, flanked by large tracts of recharge-free basin floor.

Forebay Aquifer Subbasin Groundwater Sustainability Plan

Salinas Valley Basin Groundwater Sustainability Agency | January 13th, 2022

The 2014 California Sustainable Groundwater Management Act (SGMA) requires that medium- and high-priority groundwater basins and subbasins develop Groundwater Sustainabil

The 2014 California Sustainable Groundwater Management Act (SGMA) requires that medium- and high-priority groundwater basins and subbasins develop Groundwater Sustainability Plans (GSPs) that outline how groundwater sustainably will first be maintained for 50 years. This GSP fulfills that requirement for the Salinas Valley—Forebay Aquifer Subbasin (Subbasin, or Forebay Subbasin), which is designated by the DWR as a medium priority groundwater subbasin. Plan approved by DWR 4/27/23.

Fourth Five Year Review Report for the San Gabriel Valley Area 2 Superfund Site, Los Angeles, California

U.S. Environmental Protection Agency (EPA) | September 15th, 2022

This is the fourth Five-Year Review of the San Gabriel Valley Area 2 (Site) located in the San Gabriel Valley in Los Angeles County, California. The purpose of this Five-

This is the fourth Five-Year Review of the San Gabriel Valley Area 2 (Site) located in the San Gabriel Valley in Los Angeles County, California. The purpose of this Five-Year Review is to review information to determine if the remedy is and will continue to be protective of human health and the environment. The Site addresses approximately 10 square miles of groundwater contamination in eastern Los Angeles County within the San Gabriel Valley. Groundwater contamination is believed to result from the cumulative impact of decades of improper chemical handling and disposal practices at numerous industrial operations in the Valley. The Site contamination originates at current and former industrial facilities in and near Azusa, California and extends to the southwest through portions of the cities of Irwindale, Baldwin Park, West Covina, and Industry. The most prevalent contaminants in groundwater are trichloroethylene, tetrachloroethylene, carbon tetrachloride, perchlorate, n-nitrosodimethylamine (NDMA), and 1,4-dioxane.

Fourth Supplement to State Water Resources Board Bulletin No. 11 San Joaquin County Investigation, Basic Data, Calaveras Unit 1957-58

California Department of Water Resources (DWR) | March 27th, 1959

Frequently Asked Questions Related to the CASGEM Program

California Department of Water Resources (DWR) | August 21st, 2023

Since 2009, the California Statewide Groundwater Elevation Monitoring (CASGEM) Program has tracked seasonal and long-term groundwater elevation trends in groundwater basi

Since 2009, the California Statewide Groundwater Elevation Monitoring (CASGEM) Program has tracked seasonal and long-term groundwater elevation trends in groundwater basins statewide. The program’s mission is to establish a permanent, locally-managed program of regular and systematic monitoring in all of California's alluvial groundwater basins. Senate Bill x7-6, passed by the legislature in 2009, established collaboration between local monitoring parties and DWR to collect statewide groundwater elevations, to be made available to the public. In response to the law, we developed the CASGEM program. Collecting and evaluating these groundwater data on a statewide scale is a fundamental step toward improving management of California's groundwater resources. The CASGEM program relies and builds upon the many previously established local long-term groundwater monitoring and management programs. Click here for the CASEGEM Data and Resources directory from the Department of Water Resources.