How are Western water districts managing groundwater basins?

California Agriculture (UCANR) | March 13th, 2018

Making the transition from open-access groundwater rights to sustainable groundwater management is a formidable task for newly formed groundwater sustainability age

Making the transition from open-access groundwater rights to sustainable groundwater management is a formidable task for newly formed groundwater sustainability agencies in California. As agencies begin to decide how to make equitable water allocations, how to monitor groundwater use and what mix of supply- and demand-side mechanisms to adopt to satisfy sustainability criteria, the groundwater management strategies in place across other basins in the western United States are worth studying. We surveyed 18 groundwater districts in California and other Western states to identify the management approaches and practices they have instituted. The conclusions we draw suggest a correlative rights framework of water allocation with phase-ins for heavy users; metered pumping; flexible arrangements for trading and carrying over allocations for multiple years; and incentivizing groundwater recharge, including recharge from deep percolation from crops. Rigid formulas for significantly reducing groundwater use in medium- and high-priority basins are likely to have significant negative effects on the regional economy.

How Native Americans will Shape the Future of Water in the West

New Yorker | January 27th, 2023

As a child, Stephen Lewis heard stories about a river that, for the most part, no longer flowed. “How I grew up was that it was a theft, that it was stolen from us,”

As a child, Stephen Lewis heard stories about a river that, for the most part, no longer flowed. “How I grew up was that it was a theft, that it was stolen from us,” he told me late last year. “There was what we used to call the Mighty Gila River, and now it was just pretty much dry. There was no water.” Lewis is the governor of the Gila River Indian Community (gric), a group that has occupied land south of Phoenix for centuries. When I met him, in the dining room of the Whirlwind Golf Club, which the tribe owns, Lewis had recently returned from Santa Fe. There, he’d attended a celebration marking the centennial of the Colorado River Compact, an agreement that continues to shape water politics in the Southwest. In Santa Fe, Lewis took note of a black-and-white photograph of the compact’s signers—white men in dark jackets, gathered around a wooden desk.

Hudson v. Dailey

Supreme Court of California | December 1st, 1909

Identifying organic contaminants at trespass cannabis grows on federal land in California, USA

Elsevier | September 25th, 2025

Despite the legalization of recreational cannabis in California, USA, illegal cannabis cultivation remains pervasive, partly through the establishment of illegal cult

Despite the legalization of recreational cannabis in California, USA, illegal cannabis cultivation remains pervasive, partly through the establishment of illegal cultivation on public lands (trespass grows). These operations often illegally divert water for irrigation and perform unauthorized applications of chemical fertilizers and pesticides. This work investigates a broad suite of these chemicals, focusing on their persistence in topsoil and presence in water and bed sediment in adjacent streams. Quantitative analyses of pesticides were conducted (183 compounds in water; 176 in topsoil/bed sediment), supplemented by qualitative nontargeted screening at three trespass grows that had no active cultivation for 8 months to 2 years. Targeted multi-residue analysis of topsoil detected the insecticides bifenthrin, cyfluthrin, malathion and imidacloprid (with concentrations up to 38 ng/g dry weight, d.w.), and the fungicides fluopyram, myclobutanil, and triadimefon (concentrations up to 8.1 ng/g d.w.). No pesticides were detected in the companion water or streambed sediment samples from adjacent streams. In addition, no water samples were found to have measurable estrogenic activity. Nontargeted screening uncovered additional pesticides (i.e., spiromesifen, trinexapac) in the topsoil and cannabis-related compounds (i.e., cannabidol, delta9-tetrahydrocannabinol) in both topsoil and streambed sediment suggesting the likelihood of offsite transport of cannabis related compounds. Phthalate plasticizers, rubber-related compounds, pharmaceuticals and personal care product chemicals were detected in topsoil, water, and streambed sediment and may be related to extensive irrigation infrastructure installed at these trespass grows. This work begins to establish a contaminant profile associated with illegal cannabis growing activities, providing a foundation for future research focused on their potential ecological impacts.

Implementing Climate-Smart Conservation

Public Policy Institute of California (PPIC) | March 4th, 2025

In our first report, Climate-Smart Tools to Protect California’s Freshwater Biodiversity (Sommer et al. 2024), we reviewed a broad suite of tools available to a

In our first report, Climate-Smart Tools to Protect California’s Freshwater Biodiversity (Sommer et al. 2024), we reviewed a broad suite of tools available to address the urgent problem of safeguarding California’s freshwater biodiversity in the changing climate. This toolbox includes some familiar approaches—such as various ways to improve freshwater habitat—as well as approaches that may be less familiar, more experimental, and more controversial. We also recommended the adoption of a climate-smart conservation planning process, involving a broad range of stakeholders, to prioritize the selection of tools within watersheds and to adaptively implement those tools. In this follow-up report, we explore the feasibility of implementing these tools and climate-smart planning in light of legal, policy, and institutional factors.2 Our analysis draws on an extensive review of the legal literature on ecosystem and protected species management, as well as interviews and small workshops with a wide-ranging set of 45 experts from all over the state. These experts are working on the frontlines of ecosystem policy and management; they include state and federal regulators, members of the environmental conservation community, legal professionals, and representatives of many entities involved in water and land management.

Improving Water Right Enforcement Authority

California State Water Resources Control Board (SWRCB) | April 5th, 2012

The State Water Board’s enforcement authority for water right is inconsistent with its broad enforcement authority over water quality matters. The recommendations conta

The State Water Board’s enforcement authority for water right is inconsistent with its broad enforcement authority over water quality matters. The recommendations contained in this report would enhance the ability of the State Water Board to take appropriate enforcement actions over water right matters.

In the Field and In the Stream: California Reasonable Use Law Applied to Water for Agriculture

Golden Gate University (GSU) | August 1st, 2016

When it comes to fresh water consumption in California, going forward we will need to learn to do more with less. There are at least two main reasons why California will

When it comes to fresh water consumption in California, going forward we will need to learn to do more with less. There are at least two main reasons why California will need to learn to do more with less water. First, there is a growing population in the state, a population that is increasingly urban which means there will be greater demand for urban municipal domestic water supplies. Second, there are now increasing demands to leave additional amounts of surface fresh water instream. The demands for additional instream flow relate in part to the declining condition of California’s native fisheries (such as salmon, steelhead and smelt). The demands for additional instream flow also relate to  water quality and salinity concerns. With reduced fresh water flows in our coastal rivers, seawater is pushing further upriver, and increasingly saline water cannot be used for drinking or irrigating.6 With seawater intrusion, excessive upstream diversion of fresh water threatens the very supply of fresh water. The long-standing debate over water exports from the Sacramento-San Joaquin Delta, and the impact of such Delta exports on salinity, water quality and native fisheries, is perhaps the most prominent illustration of such demands for additional instream flow.

Incomplete Determination for Groundwater Sustainability Plan submitted for Owens Valley Subbasin (Basin No. 6-012.01)

California Department of Water Resources (DWR) | April 14th, 2025

Indian Reserved Water Rights Under the Winters Doctrine: An Overview

Congressional Research Service (CRS) | June 8th, 2011

Although the federal government has authority to regulate water, it typically defers to the states to allocate water resources within the state. The federal government ma

Although the federal government has authority to regulate water, it typically defers to the states to allocate water resources within the state. The federal government maintains certain federal water rights, though, which exist separate from state law. In particular, federal reserved water rights often arise in questions of water allocation related to federal lands, including Indian reservations. Indian reserved water rights were first recognized by the U.S. Supreme Court in Winters v. United States in 1908. Under the Winters doctrine, when Congress reserves land (i.e., for an Indian reservation), Congress also reserves water sufficient to fulfill the purpose of the reservation. As the need for water grows with the development of new industries and growing populations, the tension arising from the allocation of scarce water resources highlights the difficulties that often surround reserved water rights, particularly in the western states. Western states generally follow some form of the prior appropriation system of water allocation. The prior appropriation system allocates water to users based on the order in which water rights were properly acquired. Because Indian reserved water rights date back to the government’s reservation of the land for the Indians, these water rights often pre-date other water users’ claims. Although the prior appropriation system’s reliance on seniority provides a degree of certainty to water allocation, Indian reserved water rights may not have been quantified at the time of reservation. Because Winters did not dictate a formula to determine the quantity of water reserved, courts apply different standards to quantify tribal reserved water rights. As a result, other water users may not know whether, or the extent to which, Indian reserved water rights have priority. Because of these uncertainties, Indian reserved water rights are often litigated or negotiated in settlements and related legislation. This report will examine the creation of Indian reserved water rights under the Winters doctrine. It will analyze the scope of the doctrine, including the purposes for which the water right may be claimed and the sources from which the water may be drawn. It will also discuss various quantification standards that courts have used in attempting to clarify Indian reserved water rights. Finally, it will examine the effect of the McCarran Amendment, through which Congress extended jurisdiction to state courts to hear disputes involving Indian reserved water rights.

Indian Water Rights in the West

Western States Water Council | December 1st, 1983