Environment & Science

After Oroville, LA County supervisor requests immediate assessment of 14 dams

In this Feb. 11, 2017, photo released by the California Department of Water Resources, water flows over an emergency spillway at the Oroville Dam at Lake Oroville in Oroville, Calif. Water will continue to flow over the emergency spillway at the nation's tallest dam for another day or so, officials said Sunday. (Albert Madrid/California Department of Water Resources via AP)
In this Feb. 11, 2017, photo released by the California Department of Water Resources, water flows over an emergency spillway at the Oroville Dam at Lake Oroville in Oroville, Calif. Water will continue to flow over the emergency spillway at the nation's tallest dam for another day or so, officials said Sunday. (Albert Madrid/California Department of Water Resources via AP)
Albert Madrid/AP
In this Feb. 11, 2017, photo released by the California Department of Water Resources, water flows over an emergency spillway at the Oroville Dam at Lake Oroville in Oroville, Calif. Water will continue to flow over the emergency spillway at the nation's tallest dam for another day or so, officials said Sunday. (Albert Madrid/California Department of Water Resources via AP)
Los Angeles County Supervisor (District 5), Kathryn Barger, at Sorriso in Pasadena.
Maya Sugarman/KPCC


As thousands of Oroville emergency evacuees return home, Los Angeles County Supervisor Kathryn Barger asked for – and will get – a sweeping assessment of the spillways, drainage basins and overall condition of 14 dams throughout the county's 5th district.

The Board of Supervisors unanimously approved Barger’s request at its Tuesday meeting. The evaluation targets dams in L.A.’s largest district and will ensure all of the dams follow public safety standards, said Tony Bell, spokesman for Barger's office. 

All of the county's dams were built in the 1920s and 30s, yet the Board of Supervisors has never requested a comprehensive report regarding their stability, he told KPCC. 

Once maintenance workers conduct risk assessments, earthquake preparedness and retrofitting tests, the Board of Supervisors will determine how and when to address possible issues, Bell said. The assessment also intends to put on record dams that don't need further maintenance.

L.A. County has a total of 15 dams, all of which were constructed between 1920 – 1939, according to the L.A. County Department of Public Works website. And all but one exist in the 5th district. After the emergency spillway in Oroville nearly failed, and thousands of nearby residents were forced to evacuate their homes, Barger decided it was prudent to ensure a similar situation wouldn’t happen in L.A., Bell said.

“It’s important to be proactive,” he said. “In Oroville, they were saying ‘Oh, this isn’t going to be a problem,’ and next thing you know 100,000 people were evacuated. So it can change from good to bad in an instant.”

L.A. County’s 5th district covers an area of roughly 2,800 square miles and has a population of nearly 2 million, according to the Board of Supervisor’s website. There hasn’t been a dam failure in L.A. County for decades, but it’s a fact of life that living below a dam has its risks, Bell said.

In the 1920s, the St. Francis Dam in the Santa Clarita Valley failed, killing hundreds of people. In the 60s, the Baldwin Hills Dam failed, killing few but destroying hundreds of homes, Bell said.

“Any of our cities in the foothill communities below a dam could be impacted by a catastrophe,” he said. "We need to make sure those are safe – and Supervisor Barger’s motion aims to do just that."

The county’s dams are monitored and repaired 24/7, according to L.A. County Public Works. 

A cost for Barger's assessment was not completely clear, said Bell, adding that the cost associated with proactive care "pales in comparison" with any potential disasters.

The assessment of the 14 dams in District 5 will begin this week, said Bell. On Tuesday, Barger thanked her supervisors for supporting her request through a tweet, posting a photo of a local dam with the hashtag “#OrovilleDam.”

https://twitter.com/kathrynbarger/status/831634755573592064