Cathy Anderson | Sacramento Bee
Communities in Southern Sacramento County, near the Cosumnes and Mokelumne rivers, are at risk of new flood evacuations this week as more storms hit their way into northern California.
Point Pleasant residents were ordered to evacuate on Sunday, while Wilton residents raced around the clock to reinforce a levee breach by landfill district officials ahead of a storm system expected to arrive Wednesday. I was told to be ready to evacuate even if I was already there.
“We are very concerned,” said Mark Haidt, the trustee of the landfill district that manages the Cosmnes River embankment in the area. “He’s one of the few advantages of this river. It rises quickly, but in the past it has descended rapidly. Hopefully we’ll have a few days of dry weather and a few feet of current.” You can lose.”
Jay Rand, deputy director of the Center for Watershed Sciences at the University of California, Davis, said levees are important along this 80-mile river because there are no dams to slow the flow from the headwaters of the Eldorado National Forest. I’m here. As a result, he said flash floods are common after warm storms like last weekend when there was more rain than snow.
Lund said residents were not in danger despite the clear skies on New Year’s Day. When a levee breaks, the levee cannot withstand the same flow of water as it did before the break.
Floods from the New Year’s Eve storm have already overran two south county levees, weakening them before the next rains. Ms Lund said that if she lives in an area that is subject to an evacuation warning or evacuation order, she wants to leave the area.
“If I had been really close, I hope I would have been evacuated already. I would be worried if it hadn’t been flooded yet,” Lund said. “One of the dykes has collapsed and will continue to collapse. is needed.”
evacuation is the only option
Sacramento County warned residents of Point Pleasant, Granville Track, and Franklin Pond to evacuate. This is because floodwaters from the Cosms and Mouklam Rivers can travel southwest toward Interstate 5 and reach these areas. Residents could be severely cut off from traveling by car.
The California Nevada River Forecasting Center website shows the Mokurum River rose above the 17-foot flood stage on Benson’s ferry at 8 a.m. on New Year’s Day, and the site said the Mokurum River was at 21.2 a.m. early Monday morning. was predicted to reach the highest value of .
The Cosumnes River passed the flood stage by 8pm on New Year’s Eve. Lund and Kevin King, general managers of Reclamation District 1000, which manages the Natomas embankment and points north, said evacuation really was the only option.
“If you escape too late, you will be rescued by helicopter or boat,” King said. This water is very cold, maybe he is 55-60 degrees. …in the cold water here, literally within 3-5 minutes your muscles lose control and your body shuts down. ”
If residents want to store family heirlooms or non-portable items, Lund suggests storing them in the attic or on the second floor.
Kosmnes dyke weakened by the 2017 storms
In Wilton, frontier district leaders began preparing for the storm on Wednesday, placing masses of sandbags along embankments and working with farmers and ranchers to deploy them as needed. I arranged for someone to be called.
They also contracted with a rock and gravel company to truck the boulders and other necessary materials to Wilton and have them ready with the personnel to move them.
A frustrating thing for landfill officials, according to Haidt, was having to postpone strengthening seven levees damaged by the 2017 floods. when they asked for financial assistance.
Haidt said the biggest challenge in protecting the Wiltons from the Cosmnes is the accumulation of gravel and silt in the river over the years, leaving little space to hold water.
“Under rare circumstances, all kinds of work is permitted to be carried out within the river bed,” he said. So basically, we’ve had some of these high water events and the straw has narrowed, if only we could get away to clear the river bed of excess sand and gravel and do some internal dredging. I think it’s good.”
That situation isn’t going to change until Wednesday, when rain hits the region, but Haidt and Lund said there are several factors working in Wilton’s favor. A lot of snow is also expected. Precipitation is not expected to fall as quickly. And a sunny day from now until Wednesday will give enough time for the water levels in Cosmnes to drop.
Sacramento County officials said river levels could spike in the Sacramento area, so residents should heed evacuation warnings and make evacuation plans, including which route to take.
https://www.eastbaytimes.com/2023/01/02/evacuation-the-only-option-for-communities-near-still-rising-rivers-in-sacramento-county/ Sacramento County urges residents near river to evacuate