'Significant Flood Event' Could Breach Prado Dam, Put 29 SoCal Cities At Risk

CORONA (CBSLA) – The Prado Dam in Corona is vulnerable to a "significant flood event" that could breach the nearly 80-year-old dam and threaten dozens of cities downstream, federal engineers reported Wednesday.

The U.S. Army Corps of Engineers reported this week that it has upgraded Prado Dam's characterization from moderate urgency to high urgency as a result of a recent review.

Prado, located on the Santa Ana River in Corona, is an earth-filled dam which was built in 1941. The dam is normally dry, the Corps reports, and has never experienced a large enough storm to breach the spillway.

However, the latest examination determined that a significant flooding could indeed breach the spillway, which would put the approximately 1.4 million people who live in 29 cities downstream of the dam in possible danger, along with $61 billion worth of property.

Engineers are specifically concerned about how well the concrete portion of the spillway would hold up in flood event, the Corps told The Los Angeles Times.

Cities from Newport Beach to Anaheim, including the Disneyland resort, would be vulnerable, the Times reports.

According to the Corps, a modification project is expected to begin in 2021 to "reduce the risks associated with the spillway."

Amid heavy rain in February 2017, nearly 200,000 people who live downstream of the Oroville Dam in Northern California were forced to evacuate after authorities feared that its spillway might fail.

In December of 1963, the Baldwin Hills Dam failed, sending 292 million gallons of water gushing into several West Los Angeles neighborhoods. Five people were killed, 65 homes were destroyed and another 210 homes were damaged. That dam is now a park.