WATSONVILLE, Calif. (AP) — A dam break on a storm-surge river on California’s central coast quadrupled, complicating repair efforts Monday and spilling floodwaters onto farmland and farming communities — even once again atmospheric river took aim at the swampy state.
The breach in a dam on the Pahara River has widened to at least 400 feet (120 meters) since it failed Friday night, officials said. More than 8,500 people were forced to evacuate and about 50 people had to be rescued when the water rose.
Built in the late 1940s for flood protection, the levee has been a known hazard for decades with several breaches in the 1990s. In January, an emergency repair of part of the berm was carried out. A $400 million renovation is scheduled to begin in 2025.
The river separates Santa Cruz and Monterey counties, about 70 miles (110 kilometers) south of San Francisco.
Monterey County officials also warned that the Salinas River could cause significant flooding of roads and farmland, cutting off the Monterey Peninsula from the rest of the county. The city of Monterey and other communities are located on the peninsula.
Forecasters warned of more flooding, wind damage and potential power outages from the new atmospheric river, which is expected to arrive Monday night in northern and central parts of the state and move south over several days.
A massive Pacific plume of moisture stretched all the way to Hawaii.
“Avoid unnecessary travel and complete all preparations as soon as possible,” the San Francisco Weather Service said.
California has already been hit by 10 atmospheric rivers this winter, most recently a system that crashed last week, and storms driven by arctic air that reached blizzard status.
Gov. Gavin Newsom on Sunday declared a state of emergency in six more counties after previously declaring 34 counties.
An atmospheric river last week carried warm subtropical moisture that caused melting in the lower elevations of California Sierra Nevada snowpackadding to the runoff that caused rivers and streams to grow.
But there is a snow cover so deep and cold that it mostly absorbed the rain, leading to even more snowpack in the southern and central Sierras, said Daniel Swain, a climatologist at the University of California, Los Angeles.
Online data from the California Department of Water Resources showed Monday that water content in the Sierra snowpack was 207% of its average on April 1, when it usually peaks. In the southern Sierra, it was 248% of the average.
The incoming atmospheric river will not be as warm as the previous one because it has included cold air at the back end, Swain said.
While it won’t be an extreme atmospheric river, its rain will fall on saturated soils, he said.
“That’s why I’m more concerned about this one than the last one,” he said.