Priorities for California’s Water

Public Policy Institute of California (PPIC) | November 14th, 2022

This report considers the state of water in California: What changes are we seeing now, and what should we expect in the near future? Then it examines how these climate s

This report considers the state of water in California: What changes are we seeing now, and what should we expect in the near future? Then it examines how these climate shifts will impact urban and rural communities, agriculture, and the environment. Finally, it explores wet-year strategies that will help Californians get through the dry years.

Public Review Draft Report to the Legislature on the Results of the Indoor Residential Water Use Study

Publisher not available | May 11th, 2021

Water planning has always been important for urban retail water suppliers (Suppliers) but is even more critical today, as development progresses and California grapples w

Water planning has always been important for urban retail water suppliers (Suppliers) but is even more critical today, as development progresses and California grapples with frequent droughts and expected long-term climate impacts. Prior to the adoption of the Urban Water Management Planning (UWMP) Act in 1983, there were no specific requirements that mandated urban water suppliers to conduct long-term water resources planning. While many Suppliers did conduct long-term water planning, those that did not were more vulnerable to supply disruptions during dry periods and catastrophic events. Urban water management planning is needed at the local level because only local Suppliers have the knowledge and ability to tailor their planning to their unique conditions and involve their local community in the planning effort. Click here for the DWR press release

Pure Water Southern California

Metropolitan Water District of Southern California (MWD) | March 29th, 2024

Recommendations to the State Water Resources Control Board Pursuant to California Water Code Section 10609

California Department of Water Resources (DWR) | September 29th, 2022

The Department of Water Resources (DWR) is pleased to provide the following recommendations developed in response to the 2018 Legislation (Senate Bill 606 [Hertzberg] and

The Department of Water Resources (DWR) is pleased to provide the following recommendations developed in response to the 2018 Legislation (Senate Bill 606 [Hertzberg] and Assembly Bill 1668 [Friedman]) enacted in support of “Making Water Conservation a California Way of Life.” The Legislation included provisions for advancing urban water use efficiency through developing and implementing various water use efficiency standards, variances for unique uses of water, and commercial, industrial, and institutional (CII) performance measures, among other requirements. Full reports detailing our methods, technical analyses, studies, public input, and recommendations will follow. These recommendations for long-term urban water use efficiency reflect technical considerations, public input, and the imperative to continue California’s progress in urban efficient use of water for future generations. If adopted DWR's recommendations on outdoor residential and CII water use on landscapes with dedicated irrigation meters, combined with the indoor residential water use standard recommendations submitted to the Legislature jointly by DWR and State Water Resources Control Board (State Water Board), pursuant to Water Code 10609.4 (b)(1), would result in expected long-term water savings of approximately 450,000 acre-feet per year starting in 2030 – considering 2019 population and 2017-2019 water use data, the water savings are enough to supply about 1.6 million homes or 4.7 million residents for both indoor and outdoor annual water needs.

Refinement of Rice Water Consumptive Use During the Growing Season — Sacramento Valley

University of California, Davis (UC Davis) | June 6th, 2018

The purpose of this study is to evaluate crop water use for the most commonly grown paddy rice variety grown in the Sacramento Valley, M206, based on field data collected

The purpose of this study is to evaluate crop water use for the most commonly grown paddy rice variety grown in the Sacramento Valley, M206, based on field data collected from 2007 through 2009, and from 2011 through 2013. M206 was identified by the University of California (UC) Cooperative Extension Farm Advisors as the most commonly grown rice variety in the study area. Phase I of this study was conducted by the University of California, Davis (UC Davis), under contract with DWR. A brief description of both Phase I and Phase II have been included here to provide orientation as the progression of the work and linkages between each phase regarding the study results. 

Refinement of Rice Water Consumptive Use During the Growing Season — Sacramento Valley Phase II — Cal-SIMETAW Model Study

California Department of Water Resources (DWR) | June 6th, 2018

The purpose of this study is to evaluate crop water use for the most commonly grown paddy rice variety grown in the Sacramento Valley, M206, based on field data collected

The purpose of this study is to evaluate crop water use for the most commonly grown paddy rice variety grown in the Sacramento Valley, M206, based on field data collected from 2007 through 2009, and from 2011 through 2013. M206 was identified by the University of California (UC) Cooperative Extension Farm Advisors as the most commonly grown rice variety in the study area. Phase I of this study was conducted by the University of California, Davis (UC Davis), under contract with DWR. A brief description of both Phase I and Phase II have been included here to provide orientation as the progression of the work and linkages between each phase regarding the study results. 

Residential End Uses of Water, Version 2: Executive Report

Water Research Foundation (WRF) | April 14th, 2016

It is essential for water providers and the urban water supply industry to have a detailed understanding of how water is usedin residential settings. While water

It is essential for water providers and the urban water supply industry to have a detailed understanding of how water is usedin residential settings. While water use in homes was studied as early as the 1940s, interest intensified after the Energy Policy Act of 1992, which sought to improve energy and water efficiency. This Act established maximum flow rates for new residential toilets, showerheads, and faucets. Later federal regulations included clothes washers. Water efficiency in homes has also been encouraged by programs like EPA’s WaterSense. Until now, the most significant residential end use study conducted in North America was the Water Research Foundation’s 1999 report, Residential End Uses of Water (REU1999) (Mayer et al. 1999). WRF’s newreport, Residential End Uses of Water, Version 2 (REU2016) (DeOreo et al. 2016), provides an updated and expanded assessment of water use. It includes more varied study site locations, hot water usage data, more detailed landscape analysis, and additional water rate analysis. The new study identifies variations in water use by each fixture or appliance, providing detailed information and data on changes since the REU1999 study. Looking to the future, the study’s research evaluates conservation potential, and includes predictive models to forecast residential demand. The decline in water use across the residential sector, even as populations increase, poses new challenges for water utilities. Information on single family home water consumption is significant for utility rate and revenue projections, capital planning (water supply and infrastructure needs), daily operations to provide water, water efficiency programs, and more.

Residential Water Conservation and the Rebound Effect: A Temporal Decomposition and Investigation

American Geophysical Union (AGU) | April 25th, 2023

Safe Clean Water Water for Los Angeles County Residents

Los Angeles County Department of Public Works (LACDPW) | November 7th, 2017

We live in a water-scarce area, and forces outside of our control can threaten our local water resources, including lakes, rivers and beaches. LA Count

We live in a water-scarce area, and forces outside of our control can threaten our local water resources, including lakes, rivers and beaches. LA County residents rely heavily on imported water from the Sierra Mountains, the Central Valley and even from states as far away as Colorado. Climate change is causing more and more extreme weather conditions, making these remote sources more unreliable . The impacts of the recent five-year drought were widely felt here. Rainfall is an essential, local source of LA’s water . Rain runs through local rivers, creeks and streams and can be absorbed underground, replenishing groundwater, which is a local source of drinking water. However, because so much of our region is paved over, when we do experience heavy rain, too much of that precious water is lost to the ocean before we can capture it for use. Our local water resources are also threatened by toxins and pollution as stormwater runs through streets and over-paved areas into our rivers, creeks and streams. Pollution flows onto our beaches and into the ocean, posing a public health risk and harming marine life.

Santa Clara Valley Water District 2015 Urban Water Management Plan

Santa Clara Valley Water District | May 1st, 2016

The Urban Water Management Planning Act (UWMP Act) (Division 6 Part 2.6 of California Water Code §10610 - 10656) requires the preparation of an Urban Water Management P

The Urban Water Management Planning Act (UWMP Act) (Division 6 Part 2.6 of California Water Code §10610 - 10656) requires the preparation of an Urban Water Management Plan (UWMP) every five years by water suppliers that provide over 3,000 acre-feet of water annually or serve water for municipal purposes either directly or indirectly to 3,000 or more customers. The Santa Clara Valley Water District (District) meets the definition of an urban water supplier and has prepared UWMPs since 1985. This 2015 UWMP documents important information on water supply, water usage, recycled water, water conservation programs, water shortage contingency planning, and water supply reliability in Santa Clara County. It also serves as a valuable resource for water supply planners and policy makers, and addresses the water supply future of Santa Clara County over the next 25 years. The 2015 UWMP updates and supersedes all previous UWMPs.... The District is an independent special district that provides wholesale water supply, groundwater management, flood protection and stream stewardship. Its service area includes all of Santa Clara County, which is located at the southern end of San Francisco Bay (Figure 3-1). The county encompasses approximately 1,300 square miles and has a population of about 1.9 million. Most water use occurs on the valley floor between the Santa Cruz Mountains to the west and the Diablo Range to the east. Northern Santa Clara County is home to Silicon Valley and the valley floor is highly urbanized. Southern Santa Clara County has some urban development, but much of the land use is still rural and agricultural. Click here for appendices