They did not find any evidence of a mythical sea monster or mobsters hiding in cement shoes or long-lost treasure boxes.
Scuba divers spent over a year cleaning Lake Tahoe's 72-mile shoreline. They came away with tons and tons more trash.
Divers and volunteers have meticulously sorted and recorded the locations and types of the waste since May last year.
This week's dives, which included dozens of divers, were part of an unprecedented effort to find out more about the sources and possible harm that plastics can cause in the famous alpine lake at the California-Nevada border.
The organizers have also been on a journey through folklore, history, and development of the lake atop Sierra Nevada. It holds enough water for all of California to cover 14 inches.
The Washoe Tribe fished turquoise-blue Tahoe for hundreds of years before westward expansion brought railroads, timber barons, and finally Gatsby-like decadence into what was a playground for rich and famous.
Elias J. built Tahoe's first casino in 1902. Elias J. Baldwin owned large areas of east Los Angeles. He also built the famous Santa Anita horsetrack in 1907. For decades, large lakefront estates arose, including one that was used to film "Godfather II."
According to clean-up organizers, one of the most common questions locals have is whether any gangster remains are found near the north shore. Frank Sinatra was allegedly involved in fraternizing with organized criminal bosses at Cal-Neva's hotel-casino during the 1960s.
Most of the recovered debris consisted mostly of bottles, tires and fishing gear.
Colin West, the founder of Clean Up the Lake, a non-profit environmental group, stated that there have been many surprises.
Divers think they spotted shipwreck planks near Dead Man's Point, where tribal tales tell of a Loch-Ness-Monster-like creature - later dubbed "Tahoe Tessie''- living beneath Cave Rock.
West stated that they have also found "No Littering", engine blocks, lamp posts and a diamond ring. He also pointed out "those funny, fake plastic birds that sit on boats to scare away birds."
"It's astonishing to see how much rubbish has accumulated underneath what appears to have been such a beautiful lake," stated Matt Levitt (founder and CEO of Tahoe Blue Vodka), who has donated $100,000 to the cleanup.
His business is one of many, including hotels, casinos, and ski resorts that are dependent on the 15,000,000-plus visitors who visit each year to take in the view Mark Twain called "Roughing It" 1872 as "the fairest picture the entire earth offers."
Levitt stated, "It's our economic engine."
While most volunteers and contributors were motivated to beautify the lake, scientists are more interested in what happens after the litter has been piled up.
Since years, shoreline cleanups have been taking place across the country, from Arizona to the Great Lakes and Pennsylvania to Florida. However, the litter is disposed of in garbage bags and recycle bins.
Every piece of the 189 Tahoe dives, which reached 25-foot depths, was recorded by GPS and then categorized into metal, plastic and cloth.
International research is increasingly showing that plastics can be broken down into smaller pieces called microplastics.
Scientists continue to study the human health and effects of these tiny pieces. The National Academy of Sciences stated in December that the United States, the largest plastics-waste producers in the world, should reduce its plastics production. Plastics end up in the oceans and rivers.
Zoe Harrold is a biochemist who led researchers at the Desert Research Institute (Reno) that discovered microplastics in Tahoe in 2019. She was the author of Clean Up the Lake 2021, a report covering a 6-mile (10-kilometer long) pilot project.
Harrold stated that if the submerged litter is left alone, it will continue to degrade and release microplastics and leachates into Lake Tahoe’s azure waters.
This cleanup is half-century ago, when scientists began measuring Tahoe's diminishing clarity and the basin experienced explosive growth.
The 1960 Winter Olympics in Tahoe City received most credit for their success. It was the first ever television broadcast and introduced the world the lake with its snow-covered peaks.
According to the U.S. Geological Survey, Tahoe's population increased from 10,000 to 50,000 in 1960 to 90,000. In the summer, it reached 90,000. The peak days are now close to 300,000.
West stated that the majority of the things we are pulling out are the result of the human impact of creating, living, and building communities in the Lake Tahoe area.
West's group will dive at other Sierra lakes this year, including June Lake east Yosemite National Park. Future Tahoe searches will be expanded to deeper depths.
The Tahoe Fund, a non-profit organization, has also raised $100,000 to help with the cleanup. Artists are being commissioned by the Tahoe Fund to create a sculpture out of Tahoe's trash for an event center in Stateline, on Lake's south shore.
Amy Berry, Tahoe Fund CEO, stated that the Tahoe Fund hopes to inspire environmental stewardship and remind Lake Tahoe residents that everyone can take care of it.
CBS News' Anna Werner reported that scientists believe climate change may have also affected Take Tahoe's water temperature and, thus, its clarity. The lake is visited by 15 million people annually. Matt Meunier, a diver, stated that dive trips to clean up the lake's bottom found old trash.
He said, "And when I refer to old trash, I mean the '60s and '70s." "Beer cans and soda cans and church key cans are all from the past."
Scientists measure the lake's clarity every year by dropping a disc of white material and measuring how far they can see. Geoff Schladow, a professor at UC Davis, said that it is an "important indicator" of the health of the lake.
It was approximately 80 feet clear when it was measured in 2019. This means that you can see the disc 80 feet below. However, clarity in the lake was only 100 feet 20 years ago. Scientists are trying to reverse this trend.
