Threat to Tahoe’s clarity seen

Twenty years ago, scores of state and regional agencies, landowners and conservationists hammered out a comprehensive agreement that dictated virtually every aspect of future development at Lake Tahoe, save one: how many piers, slips and buoys would be allowed along the lake’s 72 miles of shoreline.

Today, the planning process is drawing to a rancorous conclusion with a proposal by the Tahoe Regional Planning Agency to allow the construction of up to 230 piers, 1,862 buoys and 235 boat slips to be built around the lake over the next 22 years. If development reaches the limits allowed by the plan, the high alpine lake eventually could hold nearly 1,000 piers, 6,300 buoys and 3,000 boat slips.

All development at the lake is subject to guidelines intended to safeguard the lake’s most cherished and vulnerable asset: the deep blue color that has been fading steadily. The states of Nevada and California as well as a nonprofit conservancy spend millions of dollars annually to preserve the clarity and quality of the lake water.

Critics of the plan say adding so many structures would stir up muck and make the lake more opaque, especially close to shore. Tahoe’s water clarity has declined to about 74 feet from the historic high of 100. Lake Tahoe is the nation’s second-deepest lake at 1,625 feet.

The state Environmental Protection Agency says the proposal does not provide sufficient scientific analysis of proposed air and water quality monitoring.

In addition, the California State Lands Commission contends that the plan would restrict public access to Tahoe’s beaches.

Details of the proposals are contained within the Shorezone Plan, which is expected to be adopted next month by the regional planning agency’s governing board. The agency calls the plan a compromise, an attempt to protect the lake while appeasing Tahoe’s various constituencies.

“I’ve always prided myself in being able to find middle ground for contentious issues, but this is one that nobody seems to be satisfied with,” said John Singlaub, executive director of the Tahoe Regional Planning Agency. He said the focus was to find a way to reconcile the lake’s expanding recreation demands with existing curbs on pollution. “We’ve struggled to find what a balance is, and we’ve got a lot of protections for the lake built in.”

“It keeps coming back to the same things,” said Jan Brisco, executive director of the Tahoe Lakefront Owners’ Assn. “The tone has been very civil, but we are also weary -- those of us who have been doing it so long. Everyone wants this off their desk.”

Brisco said that although maintaining public access to Tahoe’s beaches is a laudable goal, any new plans have to consider the rights of property owners whose homes adjoin the beaches. She said beachgoers sometimes fail to respect homeowners’ property.

The Shorezone plan would lift a 20-year moratorium on buoys and pier construction on about two-thirds of the lake -- areas that the planning agency identified as sensitive to fish populations. Singlaub says the ban is no longer necessary because decades of scientific study have concluded that there is no longer any reason to suggest that piers are detrimental to fish.

The agency estimates that over the next 22 years, boat traffic on the lake will increase by 30%, or 60,000 motorized boat trips.

The proposal also would institute what the planning agency says would be the nation’s first environmental boating plan, called the Blue Boating Program. Boats would be issued a sticker certifying, among other things, that the vessel’s engine is properly maintained and that the hull is free of invasive weeds.

Though most concerns about clarity focus on the deep water in the middle of the lake, some scientists say the new plan could cloud shallow areas by encouraging algae growth. Experts say the plan does not adequately address how piers and slips might change the water closer to the shore, where the majority of people spend their time.

“I think its impact on the clarity of the deep water is likely to be minimal,” said S. Geoffrey Schladow, director of the UC Davis Tahoe Environmental Research Center. “Of increasing concern is the near-shore clarity. I looked at the report, and to me it’s not clear that it’s been taken into account.”

Schladow called for the regional planning agency to provide the plan’s scientific underpinning to the Lake Tahoe Science Consortium for independent, peer review.

Singlaub said his agency planned to reconvene meetings with state and local groups to provide additional information.

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julie.cart@latimes.com