Groundwater Management Principles and Strategies to Monitor, Analyze and Minimize Impacts to Drinking Water Wells: A Framework for State Action to Support Drought Resilient Communities

California Department of Water Resources (DWR) | December 15th, 2021

This framework was developed in response to support drinking water access for groundwater-dependent communities.

This framework was developed in response to support drinking water access for groundwater-dependent communities.

Groundwater Sustainability Assessments: A Review of the Department of Water Resources’ Determinations on Groundwater Sustainability Plans in Critically Overdrafted Basins

Groundwater Leadership Forum (GLF) | August 31st, 2022

Of the 46 GSPs submitted in January 2020, the Department of Water Resources (DWR) determined eight GSPs to be adequate and 34 GSPs to be incomplete. In this paper we eval

Of the 46 GSPs submitted in January 2020, the Department of Water Resources (DWR) determined eight GSPs to be adequate and 34 GSPs to be incomplete. In this paper we evaluate to what extent DWR’s determinations provide oversight on the key issues of drinking water, disadvantaged communities, the environment, stakeholder involvement,and climate change. We summarize the corrective actions that DWR is recommending or requiring, as well as compare DWR’s determinations to the assessment of 31 GSPs that we conducted in 2020. We also reviewed the 11 comment letters submitted by the State Water Resources Control Board (SWRCB), 25 comment letters submitted by the California Department of Fish and Wildlife (CDFW), and seven comment letters submitted by the National Oceanic and Atmospheric Administration’s National Marine Fisheries Service (NMFS) to compare deficiencies identified in GSPs across agencies.

Guidelines for the Small Community Drought Relief Program

California Department of Water Resources (DWR) | September 20th, 2022

Human Costs of Nitrate-contaminated Drinking Water in the San Joaquin Valley

Pacific Institute | March 1st, 2011

While most Californians take for granted that safe water is readily available at the turn of a tap, a growing number of communities, primarily in the San Joaquin Valley a

While most Californians take for granted that safe water is readily available at the turn of a tap, a growing number of communities, primarily in the San Joaquin Valley and other agricultural areas of the state, face very real impacts from nitrate contamination of the drinking water sources serving their homes and schools. New research led by the Pacific Institute, The Human Costs of Nitrate-Contaminated Drinking Water in the San Joaquin Valley, finds that nitrate contamination of groundwater has wide-reaching effects on California’s health, economic vitality, and environmental well being, disproportionately affecting low-income households and Spanish-speaking residents. The analysis brings a stark reality check to the fore as the Central Valley Water Board considers a new regulatory program for irrigated lands, the primary source of nitrate contamination in the San Joaquin Valley. There have never been any regulatory requirements on irrigated agriculture to protect groundwater from fertilizers, which are the primary source of nitrate in the valley. Nitrate levels have increased dramatically in drinking water supplies over the last few decades. The new study, The Human Costs of Nitrate-Contaminated Drinking Water in the San Joaquin Valley, a collaboration of the Pacific Institute, Community Water Center, Clean Water Fund, and California Rural Legal Assistance Foundation, focuses on the household costs of avoiding nitrate-contaminated drinking water connected to community water systems and the costs to these systems of removing or avoiding nitrates, and it points to key policies and further research needed to better understand and resolve this entrenched challenge. The eight-county San Joaquin Valley has some of the most contaminated aquifers in the nation: 92 drinking water systems in the San Joaquin Valley had a well with nitrate levels above the legal limit from 2005-2008, potentially affecting the water quality of approximately 1.3 million residents. In addition to public water systems, the State Water Board sampled 181 domestic wells in Tulare County in 2006 and found that 40% of those tested had nitrate levels above the legal limit.

Inadequate Government-Led Water-Quality Monitoring Hinders Improvement Efforts in the Salton Sea

University of California, Los Angeles (UCLA) | September 4th, 2025

California’s largest inland body of water, the Salton Sea, has faced severe environmental degradation, leaving lasting impacts on surrounding desert communities. Situat

California’s largest inland body of water, the Salton Sea, has faced severe environmental degradation, leaving lasting impacts on surrounding desert communities. Situated between Riverside and Imperial counties, the lake has endured the effects of jurisdictional challenges, climate change, and unsustainable agricultural practices that have exacerbated nutrient pollution to levels surpassing those found in most lakes across the United States. Data collected over 16 years of quarterly government sampling and 12 months of high-frequency sampling—conducted collaboratively by local communities and the University of California, Los Angeles—consistently reveal high concentrations of nitrates and dangerously low oxygen levels in the water column. These nutrient-rich conditions create an environment conducive to hydrogen sulfide emissions, which persist around the Salton Sea at levels that exceed health standards and raise ongoing concerns within the community. The State of California and the federal government are contractually obligated to restore the Salton Sea. To address the water-quality issues and their consequences, we recommend a combination of environmental and economic remediation efforts aimed at improving the Salton Sea’s ecosystem and its resulting impact on nearby communities.

Inequitable patterns of US flood risk in the Anthropocene

Nature Portfolio (Springer Nature) | January 31st, 2022

Current flood risk mapping, relying on historical observations, fails to account for increasing threat under climate change. Incorporating recent developments in inundati

Current flood risk mapping, relying on historical observations, fails to account for increasing threat under climate change. Incorporating recent developments in inundation modelling, here we show a 26.4% (24.1–29.1%) increase in US flood risk by 2050 due to climate change alone under RCP4.5. Our national depiction of comprehensive and high-resolution flood risk estimates in the United States indicates current average annual losses of US$32.1 billion (US$30.5–33.8 billion) in 2020’s climate, which are borne disproportionately by poorer communities with a proportionally larger White population. The future increase in risk will disproportionately impact Black communities, while remaining concentrated on the Atlantic and Gulf coasts. Furthermore, projected population change (SSP2) could cause flood risk increases that outweigh the impact of climate change fourfold. These results make clear the need for adaptation to flood and emergent climate risks in the United States, with mitigation required to prevent the acceleration of these risks.

Inflation Reduction Act of 2022

United States Congress | August 6th, 2022

Click "get document" for the entire bill. Scroll below to see its drought relief amendment.

Click "get document" for the entire bill. Scroll below to see its drought relief amendment.

Kaweah Subbasin Staff Assessment

California State Water Resources Control Board (SWRCB) | October 14th, 2025

The Kaweah Subbasin is managed by three GSAs: East Kaweah GSA, Greater Kaweah GSA, and Mid-Kaweah GSA (collectively, the Kaweah GSAs or GSAs). Each GSA wrote their own GS

The Kaweah Subbasin is managed by three GSAs: East Kaweah GSA, Greater Kaweah GSA, and Mid-Kaweah GSA (collectively, the Kaweah GSAs or GSAs). Each GSA wrote their own GSP, East Kaweah GSP (EKGSP), Greater Kaweah GSP (GKGSP), and Mid-Kaweah GSP (MKGSP). The three GSPs are tied together by a coordination agreement. The primary use of groundwater within the subbasin is irrigated agriculture; in 2020, irrigated agriculture used more than 94 percent of the groundwater in the subbasin (2024 Coordination Agreement, Appendix 1, p. 27). The subbasin is critically overdrafted, which means that groundwater is pumped out of the subbasin faster than it is recharged by precipitation and other sources. On average, the amount pumped from the subbasin in a year is 104,000 acre-feet greater than the amount recharged (2024 GKGSP p. 1-1). Overdraft can cause the land surface to sink, potentially damaging infrastructure and reducing aquifer storage. In addition, overdraft threatens groundwater levels and drinking water quality and could have disparate impacts on communities that rely on shallower groundwater levels. Due to historic and political factors, many of these are economically disadvantaged and communities of color. As of 2022, the subbasin has an estimated population of 296,632 people with most of the population being Hispanic or Latino (60.6%) followed by white (31%) (American Community Survey, 2022). The average annual household income within the subbasin in 2022 is $71,000, which is significantly less than the state average of $91,551 (ibid.).

Large and inequitable flood risks in Los Angeles, California

Nature Portfolio (Springer Nature) | October 31st, 2022

Flood risks in the United States have historically been underestimated, particularly with respect to human well-being and within low-wealth and marginalized communities.

Flood risks in the United States have historically been underestimated, particularly with respect to human well-being and within low-wealth and marginalized communities. Here, we characterize a fuller range of risks in Los Angeles, California, using a quantitative framework that intersects flood hazards from rainfall, streamflow and storm tides with measures of exposure and vulnerability including ethnicity, race and socioeconomic disadvantage. We find that between 197,000 and 874,000 people (median 425,000) and between US$36 billion and US$108 billion in property (median US$56 billion) are exposed to flooding greater than 30 cm within the 100-year flood zone, risk levels far above federally defined floodplains and similar to the most damaging hurricanes in US history. These risks are disproportionately higher for non-Hispanic Black and disadvantaged populations, burdening communities that may have greater challenges recovering and reinforcing socioeconomic inequities. Our framework creates opportunities for transparently and equitably reducing flood risks in urban areas.

Law and Policies that Address Equitable, Climate-Resilient Water and Sanitation (Part 2)

Pacific Institute | October 21st, 2024

In the United States, federal, tribal, state, and local laws and policies exist to govern the provision of water and sanitation services to communities and homes. The law

In the United States, federal, tribal, state, and local laws and policies exist to govern the provision of water and sanitation services to communities and homes. The laws are designed to ensure the protection of public health and the environment; deliver sufficient, safe water for drinking, bathing, cooking, and other household needs; and remove and treat domestic (i.e., household) waste. People without complete plumbing or safe water live within the “water access gap.” As explored in the first report in this series, climate change—from extreme temperatures to droughts, floods, extreme storms, and wildfires—is making it hard to close this gap and keep it from growing. Water and sanitation systems in frontline communities already feel the disproportionate “first and worst” impacts of climate change to these systems and to their access to water and sanitation. Laws and policies should help anticipate and plan for the incremental and catastrophic impacts of climate change and protect those most harmed by the effects. Unfortunately, in most cases, the climate is changing faster than the law can respond, thereby leaving frontline communities’ water and sanitation systems vulnerable to damage or destruction. (Click here for Part 1)