latest news The risk of catastrophic flooding has decreased in Lake Tulare
The risk of catastrophic flooding in the Lake Tulare Basin has diminished as cool temperatures have prevailed this spring, flattening the melting curve of the Sierra’s epic snowpack, state officials said Monday.
We “do not anticipate damage as severe as what we perhaps envisioned several weeks ago,” Brian Ferguson, deputy director of crisis communications for the Governor of California’s Office of Emergency Services, said Monday during a briefing. ‘a press conference. “However, we would like to emphasize strongly that we did not come out of the woodwork by any stretch of the imagination.”
Just weeks ago, authorities feared that floodwaters from the melting Sierra Nevada snowpack would surge down the Tule, Kings, Kaweah and Kern rivers and topple berms, break levees and inundate towns such as than Corcoran and Stratford.
They now say their most conservative models do not project the lake to exceed a height of 184.1 feet above sea level – well below the 192 feet of newly reinforced levee protecting Corcoran, and about 2 feet higher. lower than the forecast they provided on April 21.
Indeed, Mehdi Mizani, chief engineer for the Department of Water Resources on the Lake Tulare Basin, said the latest models suggest water levels will reach around 181.1 feet on May 31, flooding around 620,000 acres. -feet.
In 1983, one of the lake’s last floods, about 1 million acre-feet inundated about 85,000 acres.
Mizani said the state’s models incorporate the combined effects of weather, reservoir releases, agricultural demands and evaporation, though they don’t account for levee reliability or strength — which could impact the extent of flooding in the event of a failure.
And the modeling process is “iterative,” he said. He and his team “are constantly working on model improvements, whether it’s just calibrating the models themselves or better understanding local operations to make sure we’re capturing them correctly.”
UCLA climatologist Daniel Swain agreed that the cool spring has helped alleviate flooding issues so far.
“We’ve been relatively lucky so far,” Swain said during a Monday briefing. “We threaded that needle – there was a lot of water coming down – but it didn’t all come down at once.”
However, the threat of the “great melt” remains a concern because much of the southern Sierra Nevada’s thickest snowpack has yet to melt.
“There’s still a tremendous amount of water up there, and I think people might be overlooking that because at low to mid elevations the snow has mostly disappeared,” Swain said.
“But at high elevations, where the vast majority of that snow water equivalent is, there are still huge snowpacks – they’re still clearing roads in the High Sierra right now that have 20 at 30 feet of snow on it” at 8,000 to 10,000 feet.
Temperatures are starting to warm, he said, and some areas along the Merced River in Yosemite National Park are under flood watch and warnings as high flows are expected in the next days.
But the main area of concern remains the Lake Tulare basin, he said, which has no outlet and is still filled with deep, standing water from this year’s winter storms. Although a warm atmospheric riverine event or prolonged heat wave could produce major flooding in the region, even gradual snowmelt threatens to worsen the current flooding.
“Corcoran and some of these towns that are literally in this basin are still very concerning,” Swain said. “Farmlands in this area are going to be flooded for months, and there is still a significant risk to populated areas in parts of the San Joaquin Valley for at least the next few weeks, and likely for the next two months.”
The state is stockpiling sandbags and other emergency equipment in case the weather changes, Ferguson said.
“While I think the most serious risk may have been averted, we don’t know what we don’t know,” Ferguson said, listing the many variables that could influence speed, strength and the amount of flowing in rivers.
“So while you know that I think the most serious risk may have been averted, we don’t know yet what we don’t know yet in terms of how fast the water comes down the mountain, what levee can contain squirrels that we are not aware of, or a million other things that we don’t necessarily control as humans,” he said.
“And so, as we look much, much better than in the past, we just want to emphasize that the public in these communities must continue to be aware of the challenges that lie ahead and that we will continue to be in this situation for at least all the month of July.