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

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