It’s hard to imagine that this quiet place once drew more visitors than Yosemite National Park.

Back then, the Salton Sea was a boom town, rising out of the desert like a Las Vegas or a Palm Springs. The American Riviera, as it was known, was full of glamour and promise.

But that was nearly a half-century ago.

“It’s not like it used to be,” said Wendall Southworth, 86, who had a vacation home on the eastern shore, at Bombay Beach, where he fished and rode dirt bikes with his family in the 1970s.

“We’d stop in the Ski Inn and have a beer. It was crowded,” said Southworth, who bought the bar and restaurant in 1994. “There used to be five bars in this little town. Now it’s just the Ski Inn and the American Legion.”

The resorts and celebrities also have disappeared, leaving brown and white pelicans alone on the glassy water. Weeds poke through cracked asphalt in waterfront neighborhoods that were laid out but never built. And the pale crust of the exposed shoreline grows more prominent each year.

The lake’s ever-expanding banks are the most telling indicator of how dire things have gotten. Experts call it an ecological disaster.

“It’s hard to envision how bad the Salton Sea will be in 10 or 15 years,” said Michael Cohen, who has spent more than a decade studying the lake for the Pacific Institute, an environmental research group in Oakland.

Here’s why:

The 350-square-mile lake, which straddles Riverside and Imperial counties, is fed by municipal wastewater and runoff from thousands of acres of agricultural fields. Inflow to the lake diminished partly because of a farm-to-city water transfer approved in 2003.

After that transfer agreement ramps up to full levels in 2017, the lake will get less than half the water it now receives.

If the lake dries up, habitat will be lost for fish, wildlife and more than 400 species of birds — many that migrate to this Pacific Flyway stop.

In turn, wind will blow sediment from the uncovered lakebed across the Coachella and Imperial valleys, which already have some of the highest asthma rates in the state. In 15 years, as much as 100,000 acres of playa will be exposed, 10 times what it is today, Cohen said.

Residents worry that fertilizers, pesticides and selenium that lurk at the bottom of the lake will be stirred by the region’s regular wind storms. They wonder what that will mean for their health.

There’s also the health of the lake to consider. The reduced inflows have boosted salinity, making the Salton Sea about 50 percent saltier than the ocean. Unchecked, the high salt content will choke out the lake’s 400 million tilapia, the last surviving sport fish at the Salton Sea.

The high salinity and fertilizer runoff regularly cause algae blooms, which starve the lake of oxygen. And that contributes to two of the Sea’s most notorious problems – fish die-offs and its stench.

The worst odor event was in 2012, when winds stirred decaying matter at the bottom of the lake and blew a rotten egg smell 150 miles across Southern California.

Air quality regulators issued two odor alerts in the Coachella Valley in September, and such events could become more common as the lake grows more shallow.

State, federal and local agencies are scrambling to head off disaster by creating wetlands on the exposed lake bed, which would accommodate wildlife and contain dust. But funding is scarce and time is short.

“We don’t want to spend any more time considering solutions. We want to start implementing them,” said Phil Rosentrater, deputy director of Riverside County’s Economic Development Agency.

‘Let it dry up’

Heading south on Highway 111 outside Mecca, the Salton Sea appears like a mirage from the desert scrub and farms of the Coachella Valley.

This spot between Anza-Borrego State Park on the west and Joshua Tree National Park on the north was a dry lake bed until 1905, when the Colorado River flooded. Water flowed for two years, settling in a drainage basin with no outlet and earning the nickname, “the accidental sea.”

Development and recreation began in the 1950s, drawing more than half-a-million visitors a year. In 1976 and 1977, tropical storms caused the Sea’s water level to rise, inundating homes, businesses, marinas and yacht clubs in Bombay Beach and Salton Sea Beach. The local economy collapsed, property values plummeted and residents fled, leaving the towns to rot.

Jennie Kelly, 65, started camping and off-roading at the Sea shortly before the flooding in the 1970s. She moved there permanently from Simi Valley in 1984, and still loves the natural beauty.

Kelly has seen the makeup of her North Shore community evolve, from retirees to young families attracted to the low cost of housing. She’s also seen the crime rate go up and she no longer knows most of her neighbors.

Kelly is frustrated by the lack of progress on fixing the sea, but saw movement begin after the odor event of 2012.

“The public used to say, ‘Let it dry up.’ They had no idea what the consequences of diminishing water levels would be. But they do now,” Kelly said. “It got their attention and serious work is being done to come up with plan and funding.”

In the late 1990s, the Sea’s fish began dying because of algae blooms. Their carcasses litter the shore and the barnacle shell sand, giving the lake an eerie quality.

Lake levels have dropped for several reasons, including wastewater treatment and recycling in Mexicali, changes in agricultural irrigation practices and other water conservation measures, and the farm-to-city water transfer known officially as the Quantification Settlement Agreement, said Tim Krantz, an environmental consultant and environmental studies professor at University of Redlands.

As part of the transfer, which sends conserved farm water to San Diego County, the state of California agreed to fund restoration of the Sea beyond the $386 million contributed by parties to the settlement. The state’s preferred plan, to build a brine sink in the middle of the lake and dike up the north and south ends for recreation and habitat, has a $10 billion price tag. The plan, identified in 2007, was never approved by the Legislature and appears unlikely to happen.

The focus now is on incremental and affordable projects that can be up and running while a long-term restoration is developed, said Bruce Wilcox, environmental project manager for the Imperial Irrigation District, which owns land around the lake.

“We’re afraid the Salton Sea isn’t going to be restored under the current plans any time soon,” he said.

Some of the smaller, interim projects built or approved for construction:

 The Torres Martinez Desert Cahuilla Indians used a federal grant to create 85 acres of shallow wetlands on their land at the north end of the Sea.

 On the southern end, at Red Hill Bay, 600 acres of dry lakebed will be turned into shallow bird habitat. The $25 million project, which calls for construction of berms to impound water, is meant to serve as a model for future developments. Construction on the joint project between the U.S. Fish and Wildlife Service and Imperial Irrigation District is scheduled to begin next year.

 The state is planning a 640-acre species habitat conservation project on the southern end of the lake to create shallow ponds for birds to feed, rest and breed.

 The Imperial Irrigation District has a Water Marine Habitat Pilot Project on the southeast end of the lake that will use an existing desalination plant to treat lake water for a quarter-acre shallow pond on exposed playa.

 The Imperial Irrigation District and Imperial County also are working on a project to combine habitat with geothermal and other renewable energy projects.

The Salton Sea Restoration & Renewable Energy Initiative would site energy projects on exposed lake bed to reduce blowing dust, and use the revenue from leases to help fund restoration of the Sea. Potential sites will be identified by mid-2015, according to the district.

The plan would develop 1,700 megawatts of electricity, enough to power more than 1 million homes, and could generate $3 billion for restoration over the next decade, irrigation district officials said.

FUNDING HOPE

On Nov. 19, the Imperial Irrigation District petitioned the State Water Board to order talks with the state to work out a funding plan for Salton Sea restoration. If the funding issue isn’t settled in six months, the district asked the state to postpone the water transfer to avoid disaster at the Salton Sea.

“The State board could say we have a public health crisis, the people of the Salton Sea basin, the Coachella Valley and Imperial Valley are suffering, are physically ill, so people in coastal Southern California can continue to water their lawns,” said Cohen of the Pacific Institute. “Maybe they’ll give a one- or two-year time out and hold back some of that water until we can figure out how to solve these problems, because all of a sudden, it’s affecting 19 million people.”

It’s been years since much attention was paid to the Salton Sea, California’s largest lake, but the tide seems to be shifting, Cohen said. And with it has come some additional funding for restoration efforts.

The Sea will benefit from some of the $485 million earmarked for the state Natural Resources Agency through Prop. 1, the water bond passed by voters last month.

Also at the state level, former Assemblyman Brian Nestande, R-Palm Desert, had proposed a quarter-cent sales tax increase in the Coachella Valley to fund a dam-like barrier on the northern half of the Sea; the proposal will be put before voters, possibly next year.

The state also approved a specialty Salton Sea license plate, which would help fund restoration efforts; 7,500 reservations must be made before the plates will be produced.

And Gov. Jerry Brown signed a budget bill in 2013 that included $2 million for the Salton Sea Authority to conduct a new feasibility study.

Concern about the ailing lake has gotten the attention of the federal government, too.

The Obama Administration has recommended $200,000 in the Army Corps of Engineers budget for fiscal 2015 to study Salton Sea restoration – the first time the federal government has proposed funding for solving problems at the lake. Earlier this year, Obama signed into law the Water Resources Reform and Development Act, which directs the Army Corps to focus on issues at the Sea.

Failure to address the Sea’s decline will be expensive, says a recent report by the Pacific Institute’s Cohen. The cost of lost habitat, lowered property values and health problems caused by blowing dust could be as high as $70 billion over the next three decades.

PROMOTING THE POSITIVES

Not all hope is lost for the Salton Sea.

In fact, Paul Quill sees it as an economic engine. He is project manager for Travertine Point, a new city planned for the northwest shore of the Sea.

Plans have been approved for the 5,000-acre development proposed by Federated Insurance that would include more than 16,600 homes, a business park and light industrial, hotels, restaurants, a marina, golf course and schools.

An infrastructure financing district around the Sea would help provide funding for restoration, and flood water from the mountains would be captured, cleaned and delivered to the Sea, Quill said.

Resident Connie Brooks also sees potential for the Sea’s future, provided it can be restored.

As executive director of the Sea and Desert Interpretive Association, Brooks spends her days trying to convince people the Sea is worth saving.

She can’t understand why so many people fail to see the beauty of the Salton Sea, a place where great blue herons, egrets and other birds swoop and glide over water that stretches as far as the eye can see.

“You can go down to the Sonny Bono National Wildlife Refuge and look at 10,000 snow geese and the most gorgeous sandhill cranes taking off in flight. The harbor in morning is filled with pelicans. I have coffee down there every morning,” she said.

Brooks’ group, headquartered at the Salton Sea State Recreation Area near North Shore, raises money for interpretive programs and children’s camps there. One of the most popular events is the free kayaking tour of the lake offered Sundays in peak season, between November and April.

The idea is to educate visitors on the Salton Sea’s wonders and challenges beyond the occasional smell. About 20 people a week take the tour, discovering partially submerged chimneys and telephone poles from a community lost to flooding in the 1970s, and they see the remains of World War II bombers that crashed during pre-war practice.

Brooks tells her groups that the sea is so long – 33 miles – that from inside a kayak, the end of the Sea appears to drop off.

Brooks favors an idea to exchange Salton Sea water with the Sea of Cortez in Baja California — more than 100 miles to the south —via pipeline or canal. Such a move would create jobs on both sides of the border and reinvigorate the economy around the lake. The cost could be shared with Mexico, she said.

“They’re still pumping money in for more research and more research and in the meantime, we’ve lost a lot of water,” she said.

Since April, the water level at the State Recreation Area harbor has dropped 12 feet.

“Something has to be done,” Brooks said.​

Contact the writer: jzimmerman@pe.com or 951-368-9586