By Kelly Zito
California regulators have given the go-ahead to a sweeping plan designed to slash by one-third the pollution and soil runoff from the communities and highways that ring Lake Tahoe over the next 15 years.
The regulations are part of a long-range effort to restore the lake’s legendary clarity to levels not seen since the late 1960s.
The California State Water Resources Control Board on Tuesday approved the first phase of a 65-year project to restore visibility to a depth of 100 feet — up from about 70 feet today. The plan, expected to be approved within months by Nevada and federal regulators, would limit erosion and discharges of phosphorous and nitrogen from four counties, one city and transportation departments in two states.
“Tahoe is unique, a treasure and known by people around the world,” said John Reuter, associate director of the Tahoe Environmental Research Center at UC Davis. “But right now, the pollution has been difficult to go after.
This gives us the roadmap we need to improve the lake’s clarity.”
Increasingly murky water in Lake Tahoe has been a concern since the region’s economy ballooned in the post-World War II years. The basin’s year-round population in the early 1950s totaled just about 10,000, jumping to 26,000 in the early 1970s and about 54,000 today. Along the way, new homes, parking lots and resorts have been built on the lake, eating up most of the meadows and marshes along the shoreline and causing water contamination, erosion and storm water runoff.
It wasn’t until clarity reached an all-time low of 64 feet in 1997, however, that then-President Bill Clinton convened a summit on the lake’s health. The summit led to a comprehensive set of goals to improve conditions on the lake known as the jewel of the Sierra Nevada.
The mandates approved this week would require chemical and sediment pollution to be cut by 32 percent. The policies, which were a decade in the making, would be the first aimed at “nonpoint source pollution,” which is essentially sediment dispersed into the lake from yards, parking lots and asphalt roads as opposed to a single industrial or wastewater facility.
If approved by Nevada and the U.S. Environmental Protection Agency, the regulations would affect Caltrans, South Lake Tahoe, and El Dorado and Placer counties in California. In Nevada, the Department of Transportation and the counties of Douglas and Washoe would be bound by the regulations.
Environmental groups welcomed California’s adoption of the so-called ”total daily maximum load” figures. But they doubt pollution or lake clarity will improve much amid what they see as the pro-development stance of the powerful Tahoe Regional Planning Authority, the two-state body created by Congress in 1969 to oversee growth in the basin.
Earthjustice staff attorney Trent Orr, for instance, worries the agency ultimately will sign off on a $250 million proposal to transform the low-key Homewood Mountain Resort on the lake’s west side into a destination spot with a four-story hotel, two lodges, swimming pools and upscale condominiums.
“In a better world, someone would have realized in the late 1800s that Lake Tahoe should have been preserved as a national park,” Orr said. “But that didn’t happen and the agency that’s supposed to be in charge of preserving the lake isn’t following its mission.”
Officials at the planning agency said they are actively trying to balance the needs of the area’s property owners with the health of a lake that Mark Twain once dubbed “the fairest picture the whole world affords.”
$1.5 billion needed
The exact equipment and source of financing for the estimated $1.5 billion needed to achieve the kind of clarity that Twain waxed poetic about are yet to be determined. But Reuter said the options range from additional treatment of storm water to planting vegetation on erosion-prone slopes to building holding ponds and allowing runoff to filter through soil before it courses into the lake. Each solution is designed to trap or remove the chemicals and fine sediments that cloud the lake and feed algae that absorb light and boost water temperatures.
The limits also promise to change radically the way Caltrans and the Nevada Department of Transportation maintain, clean and deice the roadways surrounding the lake. Recent research suggests that road deterioration, sand and salt constitute major sources of the fine particles that become suspended in lake waters.
“These highways act like virtual conveyor belts depositing particle pollution into the lake,” said Julie Regan, spokeswoman for the Tahoe Regional Planning Authority.
Next week, Regan said, Caltrans will break ground on a $40 million project that hints of the kind of work ahead to curb runoff in the Tahoe basin.
Engineers will repave a 3.3-mile stretch of Highway 50 in South Lake Tahoe, carve out filtration ponds nearby and install sidewalks to encourage walking.
“It’s a very small piece of the puzzle,” Regan said, “but it’s a step in the right direction.”
— Reach Kelly Zito at firstname.lastname@example.org