Heavy Rains Send Another California Reservoir Toward Highest Level in 20 Years

Eric Chaney
Published: February 20,2017
Heavy rains are sending another California reservoir toward flood stage, and officials say it's likely they'll have to open the spillway gates, something that has happened since 1997.
The region's over-saturated rivers and creeks are already beginning to cause problems as this second round of storms moves in, flooding streets and bringing trees and debris crashing into roadways. More than a dozen reports of flooding and debris flows have come in from as far south as Monterey and as far north as Santa Rosa, Though no deaths or injuries have been reported yet, flooding from the first round of these storms left at least seven people dead.

Marin County officials activated the county's Emergency Operations Center Monday morning.
(Marin County)

In Tuolumne County, the Don Pedro Reservoir near Hayward is threatening to overflow. The reservoir is sitting at 826 feet, with flood stage just 4 feet higher. Officials from the Turlock Irrigation District say with more rain coming, it's likely the spillway gates will likely be opened – something that hasn’t happened since 1997.
In Oroville, where heavy rains recently damaged the reservoir dam forcing the evacuation of nearly 200,000 people, officials say waters are receding behind the dam, and the reservoir is at 81 percent capacity with room for incoming runoff.
(MORE: Another Round of Dangerous Flooding, Landslides and Damaging Winds Underway in California)
A search and rescue team from the Butte County Sherrif's office rescued a family of five, including three young children, from rising waters in Chico Sunday night. The family home was surrounded by quick moving water that was waist deep at times, the sheriff's office reports, but deputies were able to bring the family to safety by boat.
Northbound Highway 101 was shut down Monday morning in Redwood City due to flooding and an accident,  KRON reports. Highway 192 in Santa Barbara was closed by downed trees and power lines. A Cal Trans tweet asked drivers to use other routes for the rest of the day.
In Marin County, officials have activated the county's emergency operation center as the storm rolls in. Already on Monday morning, a mudslide dropped debris and a large tree onto Sir Francis Drake Boulevard, briefly closing the roadway in both directions.
According to energy provider PG&E, more than 10,000 customers were without power Monday morning, and KRON is reporting average flight delays of 228 minutes at San Francisco International Airport, where 47 outbound flights and 47 inbound flights had been canceled as of Monday morning.
Officials are warning residents in northern California they need to be ready to evacuate again. Colusa County Assistant Sheriff Jim Saso told the Associated Press Sunday that even though floodwaters are receding in the farm community of Maxwell, where dozens of people sought higher ground during flooding rain earlier in the week, people need to stay alert.
"We're telling these people to keep a bag close by and get ready to leave again," said Saso. "If the water comes back up, it's going to be those areas affected."
Some northern California residents hoped patrolling levees for signs of danger and filling hundreds of sand bags will mean evacuations won’t be necessary.

Flooding covers part of the Los Gatos Creek trail Sunday morning southwest of San Jose, California.
(Instagram/anamoc)

"We have a levee response team, a sand bagging team, teams to check on what walkers checking on the levees find," San Joaquin River Club resident Paula Martin, who is helping coordinate emergency plans for the private neighborhood of 800 homes, told the AP.Martin said the community, located about 80 miles east of San Francisco in Tracy, California, decided to take action after the San Joaquin River started rising.
(MORE: What El Niño Means for 2017 Hurricane Season)
"Our community is pulling together like real champs," she said, adding that volunteers have been patrolling the levees every two hours.
The San Joaquin River at a measuring station near Vernalis — about 10 miles southeast of Tracy — remained Sunday at "danger stage," meaning it keeps approaching the top of levees, Tim Daly, a spokesman with San Joaquin County Office of Emergency Services told the AP.
"When the water gets that high and more water is coming, there is just too much pressure and levees can break," Daly said. "They can be topped."
Another area of concern is the Don Pedro reservoir, which officials said was at 98 percent capacity on Sunday. The reservoir captures water from the Tuolumne River, a key tributary of the San Joaquin.
MORE: Damaging Storms Hit Southern California

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