Water recycling in California

Water recycling in California
Name	Water recycling in California
Caption	Recycled water reservoir and treatment plant in California
Location	California, United States
Established	Early 20th century–present
Key legislation	State Water Resources Control Board; California Department of Water Resources; Safe Drinking Water Act
Technologies	Advanced treatment, membrane filtration, ultraviolet disinfection, reverse osmosis
Volume	Variable by year; municipal and agricultural reuse significant

Water recycling in California California has developed extensive programs for water recycling spanning municipal, industrial, and agricultural use, driven by drought, urban growth, and state policy. Programs integrate wastewater treatment, advanced purification, and distribution networks to augment supplies for potable and nonpotable needs. Key stakeholders include the California State Water Resources Control Board, California Department of Water Resources, regional water districts, and utilities such as the Metropolitan Water District of Southern California.

Overview and history

California's reuse history traces from early 20th-century irrigation projects to modern advanced purified water schemes involving agencies like the Los Angeles Department of Water and Power, San Francisco Public Utilities Commission, and private entities including Veolia Environnement and Suez. Landmark events influencing development include the California Water Plan, the 1976–77 California drought, and the 1991 California Safe Drinking Water and Toxic Enforcement Act environment that reshaped treatment standards. Major historical projects involve the Orange County Water District indirect potable reuse initiative and the Los Angeles River revitalization where treated water supplementation emerged. State-level commissions such as the Little Hoover Commission and advisory groups like the Urban Water Institute have periodically reviewed recycling policy.

Legal and regulatory framework

Regulation rests with the California State Water Resources Control Board, regional boards including Los Angeles Regional Water Quality Control Board, and federal statutes such as the Safe Drinking Water Act and actions by the Environmental Protection Agency. Legislative milestones include the California Recycled Water Policy and bills enacted by the California State Legislature that mandate monitoring, reporting, and distribution standards. Compliance requires coordination with agencies like the Department of Health Services (now part of California Department of Public Health) and regional entities such as the San Diego County Water Authority. Permitting intersects with water rights adjudicated in courts like the California Supreme Court when disputes arise.

Technologies and processes

Treatment pathways combine primary, secondary, and tertiary steps with advanced processes such as microfiltration, ultrafiltration, reverse osmosis, advanced oxidation processes, and ultraviolet disinfection often paired with chlorination. Infrastructure includes facilities operated by utilities like East Bay Municipal Utility District and systems designed by engineering firms including Jacobs Engineering Group and Aqua-Aerobic Systems. Monitoring relies on laboratory standards from entities like the National Water Research Institute and instrumentation vendors such as Hach Company. Process integration uses modeling from research centers like the University of California, Davis and pilot programs at institutions such as Stanford University.

Major projects and regional programs

Prominent projects include the Orange County Groundwater Replenishment System operated by Orange County Water District and Orange County Sanitation District, the Los Angeles Hyperion Water Reclamation Plant upgrades with participation from City of Los Angeles, and the San Diego Pure Water San Diego program run by the City of San Diego Public Utilities Department. The East Bay Municipal Utility District has regional reuse systems, while the Lancaster Water Reclamation Plant demonstrates municipal reuse in the Antelope Valley. Collaborative programs involve the Santa Clara Valley Water District, the Sacramento Regional County Sanitation District, and interagency partnerships with the Metropolitan Water District of Southern California.

Environmental and public health considerations

Environmental assessment involves agencies such as the California Environmental Protection Agency and the California Natural Resources Agency, with ecological impacts evaluated for watersheds like the Sacramento–San Joaquin River Delta. Public health oversight leverages the California Department of Public Health and federal guidance from the Centers for Disease Control and Prevention. Concerns addressed include contaminant control for compounds monitored by the State Water Board and emerging contaminants evaluated by the National Research Council. Environmental review often invokes the California Environmental Quality Act and mitigation strategies coordinated with agencies like the California Coastal Commission where coastal discharge or recharge are involved.

Economics, funding, and policy incentives

Funding sources include state bond measures championed by the California State Legislature, grants from the Water Infrastructure Finance and Innovation Act programs, and financing via local ratepayers coordinated by agencies such as the Bay Area Water Supply and Conservation Agency. Economic analysis draws on studies from the Public Policy Institute of California and the Pacific Institute, with investment decisions influenced by commodity pricing from entities like the Los Angeles Department of Water and Power and regional wholesale suppliers such as the Metropolitan Water District of Southern California. Incentives include state rebate programs administered by the California Energy Commission for energy-efficient pumps and federal tax provisions that have been leveraged by municipal partners.

Challenges and future directions

Future expansion faces institutional and technical barriers involving local agencies like the Santa Barbara County Water Agency, regulatory adaptation by the State Water Resources Control Board, and the need for research from centers such as the Water Research Foundation. Climate change impacts assessed by the Intergovernmental Panel on Climate Change and the California Climate Change Scoping Plan alter hydrology and increase demand for reuse. Emerging directions include direct potable reuse standards under development by the State Water Board, integration with groundwater management led by the Sustainable Groundwater Management Act implementation agencies, and cross-sector partnerships involving industry leaders like American Water Works Company and research collaborations with the University of California, Los Angeles.

Category:Water supply in California