South Coast

Water from the Colorado River

Metropolitan Water District of Southern California (MWD) | July 1st, 1931

It is the purpose of this booklet to outline the Boulder Canyon Dam project on the Colorado River and the Metropolitan Aqueduct. Furthermore, it seems pertinent to indica

It is the purpose of this booklet to outline the Boulder Canyon Dam project on the Colorado River and the Metropolitan Aqueduct. Furthermore, it seems pertinent to indicate the extent of the population, industrial and agricultural resources of the Metropolitan area, which stand behind and urgently require Colorado River development.

Water Partnerships between Cities and Farms in Southern California and the San Joaquin Valley

Public Policy Institute of California (PPIC) | October 29th, 2020

The San Joaquin Valley and urban Southern California are worlds apart in many ways. Yet each face growing water challenges and a shared interest in ensuring reliable, aff

The San Joaquin Valley and urban Southern California are worlds apart in many ways. Yet each face growing water challenges and a shared interest in ensuring reliable, affordable water supplies to safeguard their people and economies. Both regions’ water futures could be more secure if they take advantage of shared water infrastructure to jointly develop and manage some water supplies.  Increasing climate volatility is heightening concerns about droughts of the future. And two major shifts in California’s water landscape have generated new opportunities for collaboration between urban and agricultural interests. For urban areas, significant declines in water demand have reduced pressure on supplies during normal and wet years for many agencies, making reliability for future droughts the primary concern. For the overdrafted San Joaquin Valley, the requirement to manage groundwater sustainably has heightened interest in expanding water supplies and underground storage.  Partnerships between Southern California cities and San Joaquin Valley farms could help alleviate groundwater overdraft in the valley while building drought resilience in Southern California. More flexible supplies can help agencies adapt to changing conditions. By coordinating the location of infrastructure investments, agencies can use partnerships to bring the water where and when it is most needed, at least cost.  This report explores a variety of solutions that could benefit both regions. For the San Joaquin Valley, we look for ways to augment water supplies to ease the transition to groundwater sustainability, while for Southern California we explore options that would increase cities’ ability to deal effectively with extended droughts. By diversifying water supplies, building connections to share water more flexibly, and preparing for the extreme events to come, such partnerships would support Governor Newsom’s Water Resilience Portfolio, and pave the way for a shared effort to make the state’s water system more resilient to a changing climate. 

Water Quality Control Plan for the Coastal Watersheds of Los Angeles and Ventura Counties

Los Angeles Regional Water Quality Control Board (LARWQCB) | September 11th, 2014

The Los Angeles Regional Board's Basin Plan is designed to preserve and enhance water quality and protect the beneficial uses of all regional waters. Specifically, the Ba

The Los Angeles Regional Board's Basin Plan is designed to preserve and enhance water quality and protect the beneficial uses of all regional waters. Specifically, the Basin Plan (i) designates beneficial uses for surface and ground waters, (ii) sets narrative and numerical objectives that must be attained or maintained to protect the designated beneficial uses and conform to the state's antidegradation policy, and (iii) describes implementation programs to protect all waters in the Region. In addition, the Basin Plan incorporates (by reference) all applicable State and Regional Board plans and policies and other pertinent water quality policies and regulations. Those of other agencies are referenced in appropriate sections throughout the Basin Plan. The Basin Plan is a resource for the Regional Board and others who use water and/or discharge wastewater in the Los Angeles Region. Other agencies and organizations involved in environmental permitting and resource management activities also use the Basin Plan. Finally the Basin Plan provides valuable information to the public about local water quality issues. The Basin Plan is reviewed and updated as necessary. Following adoption by the Regional Board, the Basin Plan and subsequent amendments are subject to approval by the State Board, the State Office of Administrative Law (OAL), and the United States Environmental Protection Agency (USEPA).

Water Quality Control Plan for the San Diego region

San Diego Regional Water Quality Control Board (SDRWQCB) | July 26th, 2012

The San Diego Regional Board's Basin Plan is designed to preserve and enhance water quality and protect the beneficial uses of all regional waters. Specifically, the Basi

The San Diego Regional Board's Basin Plan is designed to preserve and enhance water quality and protect the beneficial uses of all regional waters. Specifically, the Basin Plan: (1) designates beneficial uses for surface and ground waters; (2) sets narrative and numerical objectives that must be attained or maintained to protect the designated beneficial uses and conform to the state's antidegradation policy; (3) describes implementation programs to protect the beneficial uses of all waters in the Region; and (4) describes surveillance and monitoring activities to evaluate the effectiveness of the Basin Plan [California Water Code sections 13240 thru 13244, and section 13050(j)]. Additionally, the Basin Plan incorporates by reference all applicable State and Regional Board plans and policies. The goal of the Regional Board is to achieve a balance between the competing needs of mankind for water of varying quality. Often times the constituents and quality of water needed to protect various beneficial uses will be different. The Basin Plan is the Regional Board's plan for achieving the balance between competing uses of surface and ground waters in the San Diego Region. Accordingly, this Basin Plan establishes or designates beneficial uses and water quality objectives for all the ground and surface waters of the Region. Beneficial uses are the uses of water necessary for the survival and well being of man, plants and wildlife. These uses of water serve to promote the tangible and intangible economic, social, and environmental goals of mankind. Water quality objectives are the levels of water quality constituents or characteristics which must be met to protect the beneficial uses. This Basin Plan also establishes an implementation program describing the actions by the Regional Board and others that are necessary to achieve and maintain the designated beneficial uses and water quality objectives of the Region's waters.

Water Quality Control Plan for the Santa Ana Region

Santa Ana Regional Water Quality Control Board (SARWQCB) | February 11th, 2016

This document is the Basin Plan for the Santa Ana Region. The Santa Ana Regions includes the upper and lower Santa Ana River watersheds, the San Jacinto River watershed,

This document is the Basin Plan for the Santa Ana Region. The Santa Ana Regions includes the upper and lower Santa Ana River watersheds, the San Jacinto River watershed, and several other small drainage areas. The Santa Ana Region covers parts of southwestern San Bernardino County, western Riverside County, and northwestern Orange County. The Basin Plan for the Santa Ana Region is more than just a collection of water quality goals and policies, descriptions of conditions, and discussions of solutions. It is also the basis for the Regional Board’s regulatory programs. The Basin Plan establishes water quality standards for the ground and surface waters of the region. The term “water quality standards,” as used in the federal Clean Water Act, includes both the beneficial uses of specific waterbodies and the levels of quality which must be met and maintained to protect those uses. The Basin Plan includes an implementation plan describing the actions by the Regional Board and others that are necessary to achieve and maintain the water quality standards. The Regional Board regulates waste discharges to minimize and control their effects on the quality of the region’s ground and surface water. Permits are issued under a number of programs and authorities. The terms and conditions of these discharge permits are enforced through a variety of technical, administrative, and legal means. Water quality problems in the region are listed in the Basin Plan, along with the causes, where they are known. For waterbodies with quality below the levels necessary to allow all the beneficial uses of the water to be met, plans for improving water quality are included. In some cases, it has been necessary for the Regional Board to completely prohibit the discharge of certain materials. Some types of discharges are prohibited in specific areas. Details on these prohibitions also appear in the Basin Plan.

Water quality for agriculture

Food and Agriculture Organization of the United Nations (FAO) | July 15th, 1985

Water Quality in Basin-Fill Aquifers of the Southwestern United States: Arizona, California, Colorado, Nevada, New Mexico, and Utah, 1993–2009

U.S. Geological Survey (USGS) | July 15th, 2014

Water Quality in California

Public Policy Institute of California (PPIC) | February 23rd, 2026

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 Resilience Plan: Rapid Assessment -- Preliminary Identification of Needs and Strategies with Significant Impact on the Region’s Water

Los Angeles County Department of Public Works (LACDPW) | May 1st, 2017

This document represents one of the items set forth in the Water Resilience Work Plan presented to the Board of Supervisors in June 2016. The Rapid Assessment pre

This document represents one of the items set forth in the Water Resilience Work Plan presented to the Board of Supervisors in June 2016. The Rapid Assessment presents some of the early findings of the research to identify the most promising approaches and related financial need. As a piece of the larger Water Resilience Plan, a first draft of which Public Works plans to present to the Board in summer 2017, the Rapid Assessment provides a targeted snapshot of the research outcomes and underscores the greatest perceived needs relevant to building regional water resilience. The context of climate change and unpredictable rainfall in Southern California has greatly diminished the reliability of imported water supplies and our ability to replenish groundwater in recent years. This new reality calls for practical, effective strategies to access significant amounts of locally available water to supplement and build resilience in the region’s water supply . Currently, the County of Los Angeles manages to capture and store enough stormwater to meet the demand of one and a half million residents each year. Research has shown that implementation of a portfolio of regional stormwater capture projects could increase this amount between two- and three-fold by ensuring the region can capitalize on less regular, more intense rain events. While other sustainable sources of water should be considered and integrated into a comprehe nsive water management strategy for the region, stormwater represents an accessible, abundant resource with limited funding opportunities. Potable and recycled water are underwritten by ratepayer revenue that also supports improvement and expansion of related infrastructure. Available funding for existing stormwater capture supports current County operations and maintenance, but is insufficient for any significant expansion. Desalination has limited dedicated funding , but relies on costly treatment options that have unclear environmental impacts for the region. Significant investment in regional stormwater capture projects would have substantial impact on local water supply while contributing to improvements in overall watershed health. Stormwater capture strategies, in particular, provide unparalleled opportunities to improve water quality and enhance communities through the integration of multi-benefit approaches. New funding opportunities will be necessary to facilitate the design, implementation, and operations of centralized projects with regional benefits.