Thứ Ba, Tháng Năm 30, 2023
HomeNewsAs temperatures rise, fear of flooding grows along Los Angeles Aqueduct

As temperatures rise, fear of flooding grows along Los Angeles Aqueduct

More than a month after major storms eroded part of the Los Angeles Aqueduct, crews are still trying to complete repairs and strengthen flood defenses in the face of a prolonged heatwave. a week with the potential to cause widespread snowmelt in the Sierra Nevada.

“We are doing the best we can, as quickly as possible,” said Paul Liu, of the Los Angeles Department of Water and Electricity. “Our teams are working 12-hour shifts.”

Historic snow and ice levels in the Eastern Sierra are expected to melt into runoff 225% of normal, or about 326 billion gallons of water that would need to be managed, DWP officials said.

And while a typical runoff season in the region could last from May to June, this year “could extend into August,” said Anselmo Collins, senior assistant general manager for water systems of the DWP said.

A man pointing towards the water channel

Paul Liu, manager of the Lake Owens Dust Reduction Program, visits the lake, where expected flooding from the record-breaking Sierra Nevada snow mass threatens dust control operations.

(Carolyn Cole / Los Angeles Times)

The DWP has begun draining reservoirs to create more storage space for the roughly 130 billion gallons of water expected to arrive in Los Angeles this spring and summer via pipeline — potentially enough to meet 80% of LA’s annual needs.

The hope is that most of the snow on the mountains will be frozen long enough to give DWP, Inyo County, state and federal disaster officials enough time to prepare for widespread flooding. Ants occur when summer temperatures soar.

LA’s lifeline to the Owens Valley has never faced such a long-term flood threat. The vulnerability of the centuries-old system was focused on March 10, when the flood destroyed a 120-foot section of the aqueduct near Olcha.

It was the first time in history that a 200-mile pipeline was disrupted by extreme weather, threatening the water supply to 4 million people in Los Angeles.

To drain, dry and repair the hole, the first DWP teams opened the floodgate 25 miles to the north.

Those discharges, however, have turned the alkaline lake bed into a floodplain that is stirring up corrosive flows that damage the diversion system, chew up 18 miles of roads and ledges, and encroach on pumping stations and facilities. High-voltage power infrastructure will cost millions of dollars and years to replace, officials said.

Now, with forecasters predicting the state’s first heatwave of the season, there will be little respite for the crews using excavators, excavators and cranes to reinforce the structures. ledges are damaged by rocks and boulders, and surround vulnerable roads and critical infrastructure with K-rail fences and walls.

A man speaking in front of the aqueduct

Adam Perez, manager of the Los Angeles Aqueduct, describes how to repair a hole caused by a flood in March.

(Gary Coronado/Los Angeles Times)

Adam Perez, the plumbing manager, said the DWP is “considering seeking reimbursement from the California Office of Emergency Services to help cover the millions of dollars it spent fixing the hole in October.” Father.”

Among the infrastructure at stake is a $2.5 billion dust control system that the city of Los Angeles has been asked to install to combat toxic dust pollution — the environmental consequences of LA dried up Lake Owens more than a century ago.

“Most of the repair work should be completed by June,” said Liu, head of the DWP dust control program. “But with all the snow still up in the mountains, our team could be out here for a long time. more than that.”

That’s not all bad news. The hum and roar of heavy machinery hasn’t stopped tens of thousands of waterfowl, gulls and seabirds from taking advantage of tens of square miles of new wetlands, incidentally created to rest. resting and proliferating on saltwater flies before completing their migratory journey to breeding grounds as far north as the Arctic.

Birds flying over a body of water

American avocets, which feed on brine flies, flutter their wings along Lake Owens, a site of the Western Hemisphere Network of Coastal Bird Sanctuary of international importance.

(Carolyn Cole / Los Angeles Times)

But elsewhere in the Owens Valley, a high stretch of desert between the Sierra Nevada and the White and Inyo Mountains, DWP officials and property owners noticed disturbing signs lurking in ponds, lakes, creeks, irrigation canals and fields were covered with melted snow.

Droughts, wildfires, floods and heavy snowfall are not new in the eastern Sierras. But this year, the region is reflecting extreme weather patterns around the world.

The April 29 salmon season opening ceremony at Crowley Lake is usually a sight with fishing enthusiasts in boats going in all directions.

Water seeped into the ground in the Lower Owens River.

Water seeped into the ground in the Lower Owens River.

(Carolyn Cole / Los Angeles Times)

But as of April 21, the lake remains frozen, and the only boating franchise on the lake announced that “it may be safe to expect delays of at least a week.”

“This is an unprecedented situation,” said Abby Thomason, owner and general manager of Crowley Lake Fish Camp. “We’re going to handle everything day by day, if the lake thaws, we’ll open it up, but we can’t say when.”

Inyo National Forest officials announced last week that “to protect the community, safety and natural resources,” they have closed several lower-elevation dirt roads “due to damage caused by damage to the lower elevations” storms and predicting spring snowmelt will affect them more.”

“We know everyone can’t wait to get out and start enjoying spring adventures on the Inyo River,” said Scott Kusumoto, acting director of Inyo National Forest, “and we are doing everything we can. to repair and reopen roads when conditions permit. “

Water surrounds a small power plant.

Water surrounds a pumping station on the recently arid Lake Owens bed.

(Carolyn Cole / Los Angeles Times)

The challenge now is to prevent the much of the Sierra melt that is expected to flow through the aqueduct this spring and summer from overflowing, flooding the lake bed, as well as fields, homes and infrastructure. business department.

DWP activity suggested mind in the Owens Valley since the early 20th century, when Los Angeles agents masqueraded as ranchers and farmers to purchase land and water rights in the area, then began building an aqueduct to collect and Water displacement has sustained Lake Owens for 800,000 years.

By 1926, the diversion that began in 1913 had drained most of Lake Owens, creating giant sheets of lung-damaging dust that were blown down towns downwind.

By court order, the DWP has spent more than $2.5 billion over the past three decades transforming the lake’s grim legacy with dust control projects including shallow flooding that reduced emissions by nearly 100%. Toxic dust is alkaline and salty.

In what is now hailed as an amazing accidental ecological success story, brine flies soon returned to thin, iridescent water colored green, red and orange due to algae and bacteria. . Then there are tens of thousands of waterfowl and seabirds that eat brine flies.

American Avocet eats salt water on Lake Owens.

Recently, the American avocet ate flies in brine on Lake Owens.

(Carolyn Cole / Los Angeles Times)

In 2018, Lake Owens was designated a site of international importance by the Western Hemisphere Coastal Bird Sanctuary Network, joining the exclusive group of 104 areas between Alaska and the southernmost tip of the South China Sea. America is certified for its outstanding number of birds.

Last week, the repair work by utility crews on the lakebed coincided with the eighth annual Lake Owens Bird Festival, which attracts more than 100 nature lovers from across the country.

The event was co-hosted by many conservationists who played a key role in holding LA responsible for the dust storms that hit an area of ​​dormant volcanoes, spiky lava fields, and more. , rugged mountains and multi-tiered creeks.

On a recent morning, Owens Valley botanist Mike Prather, who helped organize the bird festival, observed the northern wetlands of the lakebed through binoculars, smiled, and said, “Wow! . It’s a good day for migratory birds.”

“It looks like the DWP is doing a pretty good job of protecting its investments,” he added, “as well as the wildlife here.”

Americans fly over Lake Owens.

American avocets, which feed on salt water, fly along Lake Owens, a site of the Western Hemisphere Coastal Bird Sanctuary of international importance.

(Carolyn Cole / Los Angeles Times)

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