They found no trace of a mythical sea monster, norin cement shoes or long-lost treasure chests.
But divers who spent a year cleaning up Lake Tahoe’s entire 72-mile shoreline have walked away with what they hope will turn out to be much more valuable: tons and tons of trash.
In addition to removing 25,000 pounds of underwater debris since last May, divers and volunteers have been meticulously classifying and recording the types and GPS locations of the debris.
The dozens of dives that concluded this week were part of a first-of-its-kind effort to learn more about the source and potential harm caused by plastics and other contaminants in the famed alpine lake on the California-Nevada line.
It also took organizers on a journey through the history, folklore and development of the Sierra Nevada-top lake that contains enough water to cover all of California 14 inches deep.
The Washoe Tribe fished the turquoise blue Tahoe for centuries before westward expansion in the mid-19th century brought railroads, lumber barons, and eventually a Gatsby-like decline in what became a playground for the rich and famous.
Tahoe’s first casino was built in 1902 by Elias J. “Lucky” Baldwin, who owned a large portion of East Los Angeles and built the prominent Santa Anita Racetrack in 1907. Huge lakefront estates followed for decades, including a which was used to film “The Godfather II”.
Cleanup organizers say one of the things locals ask most is whether they’ve found the remains of any gangsters near the North Shore. That’s where Frank Sinatra lost his gambling license for allegedly fraternizing with organized crime bosses at his Cal-Neva hotel-casino in the 1960s.
The debris recovered mainly consisted of things like bottles, tires, fishing gear, and sunglasses.
But Colin West, founder of the nonprofit environmental group that launched the project, Clean Up the Lake, said there have been some surprises.
Divers believe they saw shipwreck planks near Dead Man’s Point, where tribal tales tell of a Loch Ness Monster-like creature, later nicknamed “Tahoe Tessie,” living beneath Cave Rock.
They’ve also found some “No Littering” signs, engine blocks, utility poles, a diamond ring and “those funny fake plastic owls that sit on boats to scare away birds,” West said.
“It’s shocking to see how much trash has accumulated under what appears to be such a pristine lake,” said Matt Levitt, founder and CEO of Tahoe Blue Vodka, which contributed $100,000 to the cleanup.
His business is among many, including hotels, casinos and ski resorts, that depend on the more than 15 million people who visit annually to soak up the view that Mark Twain described in “Roughing It” in 1872 as the “picture most beautiful that all the earth has to offer”. “
“It’s our economic engine,” Levitt said.
And while most contributors and volunteers were primarily motivated to help beautify the lake, it’s what happens once the trash piles up on land that excites scientists.
Coastal cleanups have been taking place across the country for years, from Arizona to the Great Lakes, Pennsylvania and Florida. But that trash goes into recycling bins and garbage bags for disposal.
Each piece of Tahoe’s 189 separate dives to depths of 25 feet was recorded by GPS and meticulously divided into categories including plastic, metal and fabric.
Plastics are key because international research is increasingly showing that some types can break down into smaller pieces known as microplastics.
Scientists are still studying the extent and human damage of the small fragments. But the National Academy of Sciences said in December that the US, the world’s biggest producer of plastic waste, should cut back on plastic production because so much ends up in oceans and waterways.
Zoe Harrold, a biochemist, led scientists at the Desert Research Institute in Reno who first documented microplastics in Tahoe in 2019. She was the lead author of Clean Up the Lake’s 2021 report on a 6-mile pilot project ( 10 kilometres).
“If left in place, the continued degradation of submerged debris, particularly plastic and rubber, will continue to slowly release microplastics and leachate into the blue waters of Lake Tahoe,” Harrold wrote.
The cleanup comes half a century after scientists began measuring Tahoe’s waning clarity as the basin began to experience explosive growth.
Most credit, or blame, the completion of the interstate system for the 1960 Winter Olympics near Tahoe City. The first televised, presented to the world the lake surrounded by snowy peaks.
Between 1960 and 1980, Tahoe’s population grew from 10,000 to 50,000 – 90,000 in the summer, the US Geological Survey said. Peak days now approach 300,000.
“Most of what we’re putting out is basically the result of the human impact of recreating, living and building a community here in the Lake Tahoe region,” West said.
West’s group plans dives this year at other Sierra lakes, including June Lake east of Yosemite National Park, and will expand future searches for Tahoe to deeper depths.
The nonprofit Tahoe Fund, which also helped raise $100,000 for the cleanup effort, is commissioning artists to create a sculpture made from Tahoe trash at an event center being built in Stateline on the coast. south of the lake.
“Our hope is that it inspires greater environmental stewardship and reminds those who love Lake Tahoe that it’s up to all of us to take care of it,” said Amy Berry, executive director of the Tahoe Fund.
Like CBS News’Scientists believe that climate change has also affected Take Tahoe’s water temperature and thus clarity. And 15 million people visit the lake annually, along with the garbage they leave behind. Matt Meunier, who runs a dive business, said dive trips to clean up the bottom of the lake found old trash.
“And when I say old junk, I mean the ’60s, ’70s,” he said. “Beer cans, soda cans, church key tins from the old days.”
Scientists monitor Lake Tahoe’s clarity every year by dropping a white disk and then measuring how far down they can see it. UC Davis professor Geoff Schladow said it’s an “important indicator of how healthy the lake is.”
When measured in 2019, the lake’s clarity was about 80 feet. That means you can see that disk 80 feet down. But about 20 years ago, the clarity of the lake was 100 feet. That is the trend that scientists are trying to reverse.