MONTEBELLO (AP) — The Army Corps of Engineers has raised its estimation of flood risk from the Whittier Narrows Dam in eastern Los Angeles County.
The Corps said Monday the risk characterization has been changed from high urgency to very high urgency.READ MORE: LA County Increases Water Usage As State Drought Conditions Worsen
The earthen dam constrains the San Gabriel River and the Rio Hondo. Both are normally dry but fill during storms.
Analysis found that during an unlikely but possible storm, water released through the spillway could exceed downstream channel capacity, flooding adjacent land.READ MORE: Nearing Historic Strike Vote, Thousands Of Hollywood Workers Could Walk Off Sets Nationwide
Other failure modes involve erosion from water piping through the dam’s foundation and from water overtopping the dam.
The Corps says interim measures will begin before next winter’s rains and other measures are likely by the end of 2017. Construction of final modifications is expected to begin in 2020.MORE NEWS: LAPD Says Armed Robberies Have Become An Alarming Trend
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