L.A. County Calls for Flood Control Improvements

Recently revealed estimates put far more people in the region at risk for catastrophic flooding than previously thought.

2 minute read

December 8, 2022, 11:00 AM PST

By Diana Ionescu @aworkoffiction


Aerial view of San Gabriel River where it meets the ocean in Long Beach, California

The mouth of the San Gabriel River in Long Beach, California. | trekandshoot / San Gabriel River

The Los Angeles County Board of Supervisors wants to know how to shore up the region’s flood control infrastructure as experts predict “an increase in epic downpours” that could pose significant flood risk to many L.A. communities. Louis Sahagún reports on the story for the Los Angeles Times.

The supervisors are calling for a report from the Department of Public Works (DPW) detailing the state of existing infrastructure and plans for improving it. The motion comes in response to a recent study that highlighted the disproportionate risk faced by low-income communities of color. “The study’s unprecedented combination of high-resolution flood modeling and socioeconomic data indicates that major floods would occur between the Dominguez Channel on the west and the Los Angeles River on the east,” Sahagún writes, noting that the analysis put roughly 874,000 people and as much as $108 billion in property at risk for catastrophic flooding.

“Until recently, it was thought that a flood event of that magnitude was likely to occur every 1,000 to 10,000 years. New research, however, suggests that the chances of seeing another one of that scale over the next 40 years are about 50/50.” This makes the urgency of upgrading flood control and mitigation infrastructure more severe than previously thought. According to Mark Pestrella, director and chief engineer of the Los Angeles County Flood Control District, “The Board’s action today aligns with the county’s sustainable plan to make infrastructure improvements that reduce flood risk, increase local water supplies through stormwater capture and groundwater recharge, and improve water quality across the county.”

Tuesday, December 6, 2022 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

Get top-rated, practical training

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.

April 23, 2025 - Diana Ionescu

Close-up of "Apartment for rent" sign in red text on black background in front of blurred building

Trump Administration Could Effectively End Housing Voucher Program

Federal officials are eyeing major cuts to the Section 8 program that helps millions of low-income households pay rent.

April 21, 2025 - Housing Wire

Black and white photos of camp made up of small 'earthquake shacks' in Dolores Park in 1906 after the San Francisco earthquake.

The 120 Year Old Tiny Home Villages That Sheltered San Francisco’s Earthquake Refugees

More than a century ago, San Francisco mobilized to house thousands of residents displaced by the 1906 earthquake. Could their strategy offer a model for the present?

April 15, 2025 - Charles F. Bloszies

Spiral ramp on exterior of parking garage in downtown Spokane, Washington.

Washington State Legislature Passes Parking Reform Bill

A bill that would limit parking requirements for new developments is headed to the governor’s desk.

15 minutes ago - OPB

Missouri state capitol dome in Jefferson City, MO.

Missouri Law Would Ban Protections for Housing Voucher Users

A state law seeks to overturn source-of-income discrimination bans passed by several Missouri cities.

1 hour ago - Missouri Independent

Los Angeles, California

Op-Ed: Looking for Efficiency? Fund Intercity Buses

Much less expensive than rail, intercity buses serve millions of Americans every year, but public subsidies are lacking.

2 hours ago - Smart Cities Dive