Lost Slough levee breaks, but gets patched up for now

A levee partially broke late Thursday in the Delta region of south Sacramento County, but officials said the problem was mostly patched up by nightfall.

After days of rain and high flows along the Sacramento River, a hole emerged on a levee at Lost Slough, near I-5 in the vicinity of the Cosumnes River Preserve.

"It was actually gushing, a pretty big hole," said spokesman Matt Robinson of the Sacramento County Department of Water Resources. However, he said reclamation district crews were able to "squeeze it off to a small trickle" and the hole was expected to be completely repaired sometime Friday.

At about 9 p.m., the Sacramento County Office of Emergency Services issued a statement: “Crews have provided a temporary stable fix to the Lost Slough levee issue. Staff will continue to monitor the levee throughout the evening. Although the issue is resolved, if the situation changes there could be calls for evacuations.

“Residents who have evacuated the area are encouraged to stay out of the area throughout the evening,” it said. “Residents who have not evacuated may choose to leave. An evacuation center is open at Laguna Town Hall (3020 Renwick Avenue) in west Elk Grove. Residents are encouraged to sign up for emergency alerts at”

Earlier in the day, Sacramento emergency officials had urged residents of the rural area to safeguard livestock and consider evacuating to a shelter in Elk Grove.

Caltrans officials said crews were surveying the area around I-5 for any flooding potential. “We are currently monitoring the situation and are being kept informed by” the California Highway Patrol, said Caltrans spokeswoman Liza Whitmore in an email.

Experts said the possible levee failure, while worrisome, wouldn’t likely pose major problems for water operations in the Sacramento-San Joaquin Delta, the hub of California’s water delivery network. Officials have long feared that a major levee breach in the Delta could prompt salt water to rush in from the ocean and force a curtailment in pumping of water to the San Joaquin Valley and Southern California.

However, there’s so much water cascading down the Sacramento River that an intrusion of salt water is unlikely, said Michael George, the state’s Delta watermaster.

Still, he said a levee failure anywhere in the Delta would be troubling. “When one link breaks, it puts more pressure on other links in the chain,” he said.

Although hundreds of millions of dollars have been spent upgrading Delta levees in recent years, officials are always vigilant. The last major levee break in the Delta occurred in 2004, when a levee guarding Jones Tract collapsed.

The warning at Lost Slough came even as much of the Sacramento area was getting back to normal following this week’s storms.

Kim Nava, a spokeswoman for Sacramento County, said it wasn’t clear if the levee would fail.

“There’s a possibility, and things can turn so quickly, we wanted to get this information out,” she said.

Agencies were advised to prepare to evacuate people and livestock to higher ground.

"If you are a rancher and have animals on your property now is the time to start moving your animals and livestock to higher ground... just in case this levee does fail," said Mary Jo Flynn, Sacramento County's emergency operations coordinator, in a live Facebook video.

She said evacuees were welcome at an emergency shelter at Laguna Town Hall, 3020 Renwick Ave in Elk Grove.

“This is a dynamic situation that could change at any minute, possibly calling for mandatory evacuations,” said an alert sent to about 40 residents of the area. “Be prepared with clothes, comfort items, medications, prescription glasses, specialty items for children and seniors.”

Dale Kasler: 916-321-1066, @dakasler

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