Reclamation district officials in Wilton said Tuesday that it will cost $1.5 million to fill a gaping hole the size of a football field in the Cosumnes River levee, one of 11 trouble spots they have identified so far.
“They’ve got to solidify a road just to get all those heavy trucks in,” said Mark Hite, a trustee for Reclamation District 800 Cosumnes, which manages the levees in the area. “They’ve got trucks bringing in gravel and stuff so that the bigger trucks bringing in the big rock can get access. And they’ve already started to close the gap.”
While there are three breaches among the 11 hot spots, Hite said, there are other types of problems. For instance, he said, the crest of the levee walls crumbled in some places as floodwaters rolled over it and wore away soil, sand, gravel and boulders.
Hite estimated the costs to repair all 11 hotspots will be in the neighborhood of $10 million but that there could be other problem areas they’re not seeing because the water has yet to fully recede.
Even a six-figure repair would be difficult for this tiny district to bear, he said, because the annual budget is roughly $500,000. It depends heavily on federal dollars to maintain levee walls on a stretch of the Cosumnes River that extends from Rancho Murieta to the north down to Freeman Road in the southern area of Wilton.
Hite said they’ll have to go to state and federal officials for help to cover the cost.
The district is waging an unwinnable battle against the river, said Jeffrey Mount, who wrote the seminal book “California Rivers and Streams” in which he argued that the Cosumnes and other state rivers had historically spilled into wide floodplains and could not be contained in narrow channels.
In an interview, Mount said that Wilton residents and others living near the Cosumnes will always be at risk of flooding.
Imagine a funnel cut in half, Mount said, and you’ll begin to understand the challenge. All the water from higher elevations pours into the top of that funnel from along the watershed and then gushes into the Cosumnes, he explained.
The river naturally rises as that volume increases, he said, and those rushing waters will always find weaknesses in planning and construction.
And, Mount added, climate change has increased the number of warm storms, or so-called atmospheric rivers, like the one that inundated Northern California last weekend.
“If you’ve got a weak spot in a levee, it’ll find it,” Mount said. “And, it did – in multiple spots.”
The levees in the Wilton area were designed to meet minimum standards to contain the cost of constructing them, Mount said, and that’s generally true for most levees built in the US.
Since Hurricane Katrina laid waste to New Orleans, leaving hundreds dead in its wake, state and federal leaders have moved to strengthen urban levees. Rural areas like Wilton, however, haven’t gotten that kind of investment.
Consequently, Mount said, Wilton is “not a good place to live, and that’s the challenge. The levees that are built on the land are not in particularly great shape. They’re not robust levees. They are certainly not urban levees. They don’t meet any of the standards — the federal standards and certainly the state standards — for what we call urban levees that protect an area, so everybody who builds out there is at pretty high risk. “
The district’s charge, Hite said, is to provide 10-year flood protection. He recalled one year that the board had estimates done to see how much it would cost to bring the 34-mile stretch of levees they supervise up to 50- or 100-year protection.
While the exact number of years has escaped him, the price tag has not. It was $550 million, he said, so that turned out to be a purely academic exercise.
Hite can see the challenge of managing the Cosumnes just outside the door at his home: “The ground is obviously saturated. ... We have a little manmade creek on our property, and it’s overflowing. The horse paddocks are totally standing water. Inside the barn, the south side stalls have some water in them, but the north side is OK.”
While storms this week are expected to bring violent winds, Hite said forecasts are so far predicting that there won’t be as much rainfall as the north state got in last week’s storms. The water level on the Cosumnes River dropped 4 feet below the 40-foot monitor stage on Wednesday, but the California Nevada River Forecast Center predicts that it will rise at least 2 feet above this stage on Thursday and Friday.
However, forecasters stressed that weather patterns could shift, improving or hurting the situation.
Hite said: “Even though we know that we’ve got more water coming. It’s not going to get as high as it did on New Year’s, and so hopefully, there’s not going to be a lot of further damage.”
Crews are working to place a wall of rock all the way across the widest levee gap, making it at least as high enough to handle what forecasters are predicting, Hite said. If they can’t continue working, he said, they’ll cover it with sandbags and permeable plastic to create a makeshift weir.
This story was originally published January 5, 2023, 5:30 AM.