Lake Tahoe sub mission seeks pollution, climate answers

SOUTH LAKE TAHOE, Calif. -- A team of submariners that spent the month of May exploring Lake Tahoe and examined, among other things, evidence of an earthquake fault that may have ruptured thousands of years ago, is hoping the operation is just the beginning of their underwater explorations.

Scott Cassell, the sub's captain and founder of the non-profit Undersea Voyager Project, says his team has plans for a five-year mission to gather information and develop ideas to help restore endangered bodies of water around the world.

The goal, Cassell says, is to collect data and attract sufficient attention to prompt people and governments to halt pollution and overfishing and take other actions to protect threatened bodies of water.

A two-person submarine spent the past month cruising Lake Tahoe, examining earthquake faults, ancient submerged trees and beds of invading clams that threaten the lake.

"I think it's a very useful tool," said John Kleppe, a University of Nevada-Reno scientist who for years has researched submerged trees, some more than 3,000 years old, in Fallen Leaf Lake just west of Lake Tahoe. The trees, which grew when the lake level was lowered by lengthy drought, provide a "very good record of climate change," Kleppe said.

Lake Tahoe, 1,645 feet deep and second to Oregon's Crater Lake as the nation's deepest, has problems, including sediment pollution and algae growth diminishing the lake's famed clarity and invasive species that could forever alter its ecology, says Cassell, 47, a commercial diver, explorer and filmmaker from Pasadena, Calif. He says he has been fascinated with aquatic depths since seeing the movie 20,000 Leagues Under the Sea when he was 6.

Several other explorations are planned in the coming months in preparation for the five-year mission Cassell and colleagues hope to commence in 2011.

Cassell said he dreamed up the Undersea Voyager concept along with veteran submariner Andreas Rechnitzer in 2003 as the pair worried about failing fisheries, the sea's impact on climate and the fact that many of the Earth's oceans are unexplored. He says he decided to make the effort his "life's mission" after Rechnitzer died in 2005.

Richard Schweickert, a geology professor from University of Nevada-Reno used the sub to study an earthquake fault he says ruptured within the past few thousand years.

The resulting earthquake, Schweickert says, was likely between magnitude 6.5 and 7 — strong enough to generate a tsunami on Lake Tahoe's surface up to 30 feet high. Geologic evidence shows such tsunamis have happened there in the distant past and could again, he says.

Other team members — there were five at Lake Tahoe and plans for a total of 15, Cassell says — gushed over the experience.

"It's just magical," added Peri Best, 48, of Napa, Calif. Best is training to pilot the sub and she plunged several times below the surface during the Lake Tahoe mission.

The sub's time at Lake Tahoe was donated by manufacturer and owner SeaMagine Hydrospace of Claremont, Calif., Cassell says. Much of the additional $25,000 in expenses came out of Cassell's pocket, he says.

Cassell, who gained some fame in November 2006 as the head of a team that was the first to successfully film a giant squid in its natural habitat in the Gulf of California, also known as the Sea of Cortez, says he next plans to explore a massive island of plastic trash floating at a place where ocean currents converge in the northern Pacific Ocean.

He will be accompanied by Charles Moore, who discovered the "Great Pacific Garbage Patch" in 1997 while returning from a sailing race. Moore estimated the size of the plastic mass at twice the size of Texas, something Cassell says he hopes to verify while filming a documentary.

After that, Cassell plans an underwater circumnavigation of Santa Catalina Island and the Channel Islands off the California coast, examining fish populations and pollutants. Accompanying him, he says, will be researchers from the Scripps Institution of Oceanography, the University of Southern California and the University of California-Davis.

The planned longer-term effort, which Cassell envisions being funded by both private donations and contributions from interested governments, would involve dives in 33 countries. He says he is in negotiations for funding from Mexico.

The Undersea Voyager Project, based in South Lake Tahoe, is trying to raise $3 million to purchase a three-person sub, capable of diving 1,500 feet, for the global expedition. "Our focus is the water. What is at 1,000 feet?" Cassell said. " It's the most hostile place on the planet that supports life — the top of the abyss."

DeLong reports for the Reno Gazette-Journal