But Emmy isn’t your average diver — she’s equipped with a custom-built 600-foot fiber optic tether, cameras and detachable hands.
She also cost nearly $50,000 to build, according to Restore the Lake Depths Foundation development director Caroline Grossman.
Deep Emerald, known by loved ones as “Emmy,” is a remotely operated vehicle. Her name is inspired by Tahoe’s “jewel of the Sierra” title, as the team viewed her as the “jewel” protecting the Tahoe ecosystems.
No one has ever reached the bottom of Lake Tahoe, despite the attempts of past engineers and researchers.
So when Emmy did so last Friday, Brett Ferrari described manning the livestream from behind the scenes as a moment of “winning the space race.”
Ferrari, the social media marketing manager for Restore the Lake Depths, described the prep leading up to the dive as nervous, from concerns about water current and weather conditions. But the worries quickly faded as the day began with calm waters.
To find out what’s at the bottom of the second-deepest lake in the United States, the project started out of a partnership from Restore the Lake Depths and the Tahoe Fund, two nonprofit organizations. The research space focused on Lake Tahoe includes various organizations, but sometimes those efforts are fragmented, as funding is hard to come by, according to Grossman.
“There’s just a lot of different different hands in the pot of Lake Tahoe and the water conservation realm,” Grossman said.
One of those hands is Sudeep Chandra, a limnology professor with the Tahoe Institute for Global Sustainability at the University of Nevada, Reno.
“To see it is to believe,” he said.
As the least studied habitat within the lake, Chandra said there’s only been a few studies published about the bottom of Lake Tahoe. He added that exploring the bottom of the lake is the equivalent of learning more about the lake’s “lungs,” or the area that allows the ecosystem to “breathe.”
Chandra explained the lake’s anatomy can be equivalent to human organs. He drawed parallels between the open water to a heart and air shed to a brain.
“What ends up happening is scientists often study only one component, or we collaborate with scientists who study the other components to try to figure out what a healthy functioning lake could be like,” Chandra said.
While most of the public experience the shallow, nearshore waters of the lake, sub ecosystems exist with organisms the size of a quarter just a couple hundred feet lower. But without sun or light in the depths, most of these amphipods and “shrimp-like looking things” are blind and endemic, or only found at Lake Tahoe.
However, the lake is changing.
While there is still a presence of biodiversity, there’s been an 85 to 99% decline of different species at the bottom of the lake, Chandra said.
Excessive algae growth, known as “greening,” is affecting Lake Tahoe’s outer layer. This phenomenon is attributed to an overabundance of nutrient intake and the presence of invasive species such as crayfish and clams.
While greening is common in other U.S. lakes, it can be reflective of how well the ecosystems surrounding the lake are doing.
Air shed, or the surrounding sentiment or material in the surrounding area, affects a lake’s ecosystem. Forests and meadows can reduce the amount of sediment and particles going into the lake, allowing for better clarity. It can also affect how much greening is occurring in the lake.
In June, the Tahoe Fund, alongside Keep Tahoe Blue, launched Emerald Bay shuttles, a new shuttle service in one of Tahoe’s most popular tourist destinations in the Basin. The transportation alternative also aims to keep the air shed cleaner and to prevent air pollution that might affect the lake’s clarity.
“I love lakes,” Chandra said to the 3,200 people tuning on the livestream. “And I love lakes for all reasons.”
Preparing Emerald
For the team’s technician Chris Holmes, the dive was a personal mission and a technical milestone.
“What really drives us is the opportunity to bring people closer to something they’ve never been able to see before,” Holmes wrote in a statement. “The bottom of Lake Tahoe has been hidden from the public eye for so long, and now we have a chance to share that world — its mysteries, its beauty and its importance — with everyone.”
But most test dives resulted in bringing back a beat-up ROV with cracked lenses, broken seals and leaks in new places.
“Testing didn’t get easier as we went — it actually got harder,” Holmes wrote.
Although Restore the Lake Depths founder Lindsay Kopf had previously removed 80 tires from Lake Tahoe, she first had to learn how to drive Deep Emerald. The ROV is controlled by a joystick that Kopf has said is “her favorite video game.”
“We’re collecting footage that reveals the geology, biology and overall function of the lake,” Kopf said. “It’s a powerful tool for research, education, and protecting the lake moving forward.”
Kopf and Holmes faced another primary challenge while equipping Emmy to endure 50 atmospheres of pressure: the need to stream live 4K video.
“There were dozens of test dives done that revealed failures, weak points and surprises,” Holmes said. “Every dive came with a risk of catastrophic leaks or a total loss of control.”
While tethers on ROVs to share information with those on the surface are typically made of copper, the material could only withstand 300 feet depths before camera footage starts to experience lag, ultimately affecting the vehicle’s control.
Cue the fiber optic tether custom-built by SeaView systems. Incredibly expensive and fragile, the fiber ultimately solved signal loss and lag that other materials couldn’t.
What does Tahoe dive mean for the future?
Holmes anticipates that the dive will open doors for their nonprofits and conservation research for Lake Tahoe.
“Universities, research groups and organizations that haven’t had the resources or equipment to explore the lake at this level can now work with us,” Holmes said. “We want to provide access and data that empowers education, research and conservation.”
Since moving to Tahoe from New York City in 2003, Tahoe Fund founder Amy Berry embarks on a daily routine of hiking around before taking a photo of the lake.
“I’m still the person that goes for a hike every day and I stare out at that lake and I take a photo of the lake every day, even though it looks almost the same every day,” she said.
Berry admits that since working in this space for almost 20 years, she’s heard every theory someone can think of, one including the myth of Jacques Cousteau’s alleged descent.
“The world is not ready to know what I saw,” Cousteau supposedly said.
But there’s no evidence that the explorer was ever in Tahoe, she said.
Emmy’s first public dive is just scratching the surface of this research, and there’s significant work still ahead. As the shoreline’s clarity diminishes, Berry stressed the importance of this research for conservation efforts, especially doing it collaboratively.
“Everything we do in Tahoe is a partnership,” Berry said. “You just can’t get very far alone around here.”
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