Los Angeles County Considering World's Largest Recycled Water Program

With an historic drought pressuring agencies to source more water locally, the Metropolitan Water District is looking to expand an idea pioneered by its neighbors in Orange County.

2 minute read

September 25, 2015, 12:00 PM PDT

By James Brasuell @CasualBrasuell


"The Metropolitan Water District of Southern California is in talks with Los Angeles County sanitation districts about developing what could be one of the largest recycled water programs in the world," reports Matt Stevens.

MWD staff has already presented a "draft framework of a plan to purify and reuse as much as 168,000 acre-feet of water a year – enough to serve about twice that number of households for a year." Such a plan would require a new treatment plant and delivery facilities likely to cost in the realm of $1 billion.

The article goes into a lot of detail about how recycled potable water systems work, including examples available just to the south of Los Angeles County in Orange County. There, an indirect potable reuse system purifies water in an underground aquifer. The Orange County Groundwater Replenishment System can purify up to 100 million gallons of water per day. In their draft report, MWD officials targeted 150 million gallons per day, which would make the system the largest in the world.

As for next steps, Stevens reports that following a still-needed board approval "the agencies could launch on a 'demonstration project' at the sanitation districts’ Joint Water Pollution Control Plant in Carson in about 20 months. There, the treatment processes would be perfected on 1 million gallons of water per day while officials conduct additional studies and develop a financing plan, according to an MWD memo."

Tuesday, September 22, 2015 in Los Angeles Times

portrait of professional woman

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

Use Code 25for25 at checkout for 25% off an annual plan!

Logo for Planetizen Federal Action Tracker with black and white image of U.S. Capitol with water ripple overlay.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

May 7, 2025 - Diana Ionescu

Person in yellow safety suit and white helmet kneels to examine water samples outdoors on a lake shore.

USGS Water Science Centers Targeted for Closure

If their work is suspended, states could lose a valuable resource for monitoring, understanding, and managing water resources.

May 1, 2025 - Inside Climate News

Wide suburban road with landscaped median and light pole banners advertising local amphitheater.

End Human Sacrifices to the Demanding Gods of Automobile Dependency and Sprawl

The U.S. has much higher traffic fatality rates than peer countries due to automobile dependency and sprawl. Better planning can reduce these human sacrifices.

April 29, 2025 - Todd Litman

Close-up of pug dog sitting on woman's lap on city bus.

Seattle Transit Asked to Clarify Pet Policy

A major dog park near a new light rail stop is prompting calls to update and clarify rules for bringing pets on Seattle-area transit systems.

15 minutes ago - The Urbanist

Modular home being lifted with crane.

Oregon Bill Would End Bans on Manufactured Housing

The bill would prevent new developments from prohibiting mobile homes and modular housing.

1 hour ago - Oregon Capital Chronicle

Two people on Nashville BCycle bike share wearing helmets loking out over railing at downtown skyline.

Nashville Doesn’t Renew Bike Share Contract, Citing Lost Federal Funding

The city’s bike share system, operated by BCycle, could stop operating if the city doesn’t find a new source of funding.

2 hours ago - WKRN

Urban Design for Planners 1: Software Tools

This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.

Planning for Universal Design

Learn the tools for implementing Universal Design in planning regulations.

Comprehensive Bikeway Design Workshop

Transportation Research & Education Center (TREC) at Portland State University

Early Bird Deadline – save on your tuition fee!🚨

Institute for Housing and Urban Development Studies (IHS)