Western Water Magazine
Two States, One Lake: Keeping Lake Tahoe Blue
Lake Tahoe has a way of inspiring superlative descriptions, some of which have come from well-known people.
Mark Twain called it “surely the fairest picture the whole earth affords,” while John Muir called it the “queen of lakes” and “a kind of water heaven.”
Speaking at the annual Lake Tahoe Summit Aug. 19, former Vice President Al Gore said he was bowled over by the lake’s trademark blueness when he arrived with President Bill Clinton 16 years ago for the first Summit.
“The first time I saw it, my first thought was, ‘Are you kidding me? This is unbelievable,’” said Gore, the keynote speaker at the Summit.
Under a smattering of rain at Sand Harbor, Nev., Gore and other dignitaries reiterated the unique nature of Lake Tahoe and the special place it holds for Californians, Nevadans and visitors from around the world.
“It’s not just a lake, it’s a place,” said Joanne Marchetta, executive director of the Tahoe Regional Planning Agency (TRPA). Created in 1969, TRPA is the bi-state agency in charge of protecting Lake Tahoe. That mission has caused controversy at times as reglatory measures clash with the concerns of residents and developers.
Gore cited the inaugural 1997 Lake Tahoe Summit as a major milestone in the effort to retain and improve the lake’s clarity.
“I think the most important accomplishment was the shift from what many had begun to feel as a sense of despair to a sense of hope, and that’s really crucial,” he said.
The “Jewel of the Sierra,” Lake Tahoe is threatened by several factors, including invasive species, nonpoint source runoff and increased temperatures from climate change. TRPA was the product of the Tahoe Compact – the binding document ratified by Congress in 1968 that regulates development and oversee environmental controls in the Tahoe Basin. Nevada’s unease with what it perceived to be the Compact’s onerous regulatory nature almost resulted in the state’s withdrawal in 2011 but it has since pledged to remain engaged.
“When it comes to Nevada, you have our future commitment to do whatever it takes to continue to preserve the greatest place on earth, Lake Tahoe,” said Nevada Gov. Brian Sandoval.
Coinciding with the Summit was the release of the annual State of the Lake Report by the University of California, Davis’ Tahoe Environmental Research Center. The report found an improvement in clarity for the second straight year, with average readings better by more than 6 feet. Scientists measure clarity with a Secchi disk, a device resembling a dinner plate that is lowered into the water and submerged until no longer visible.
The disk is still visible at 75.3 feet underwater. In 1997-1998, annual clarity reached an all-time average low of 65.1 feet, the report says.
Although the improvement in clarity is a welcome sign, the report cautions that “it is important to recognize that year-to-year fluctuations are the norm, and the target must be seen as being a value that can be sustained over several years.”
One of the primary culprits for the loss of clarity is ultra-fine sediment, the small, microscopic particles that, once in the water, act to reflect sunlight. Less than one-tenth of the diameter of a human hair, ultra-fine sediment is produced by the vehicular traffic that grinds the grains of sand used in the winter to facilitate driving in snow and ice.
More than 70 percent of the ultra-fine sediment comes through urban runoff. That runoff is treated by channeling stormwater through retention basins.
Clarity is influenced by many factors, including wet and dry years that play a role in how many impurities reach the lake.
“This year we were quite fortunate,” Geoffrey Schladow, director of the Research Center, told KXPR radio Aug. 7. “It was a very dry year. While that may not be good for water resources, for clarity, that’s a good thing; with fewer pollutants and nutrients being washed into the lake.”
Conditions at Lake Tahoe are ever-changing, based on many factors, some of which people have no control over. Long-term, those changes ultimately affect the makeup of the lake itself.
Of increasing concern are conditions at what scientists refer to as the lake’s “near shore,” where clarity and invasive species issues are front and center. Scientists at Tahoe define the near shore as extending to the maximum depth of the summer thermocline – a transition zone between the mixed layer at the surface and deep, colder water below.
“As it appears we are making progress in the mid-lake, the conditions in the near shore are increasing in terms of relevance,” said Alan Heyvaert, acting senior director of the Desert Research Institute’s Center for Watersheds and Environmental Sustainability. “It’s a lot of the same issues, it’s clarity in the near shore as well as the amount of algae, but it also includes aquatic invasive species and a lot more variability in conditions than seen at mid-lake.”
Protecting Tahoe for native species and getting rid of those that don’t belong is part of the Lake Tahoe Restoration Act, (see page 10) a bill introduced by U.S. Sen. Dianne Feinstein that continues the federal government’s fiscal commitment by authorizing $415 million over 10 years.
“The time to act is now and the federal government must take a leading role,” Feinstein said Aug. 1 on the Senate floor. “Seventy-eight percent of the land surrounding Lake Tahoe is public land, primarily the El Dorado, Toiyabe and Tahoe National Forests.”
Feinstein, whose experience with Tahoe stretches back to her visits as a young girl, recalled the dire conditions at the lake when the Summit first convened.
“In 1997, it was the worst,” she said at the Summit. “Lake clarity had dropped 22 feet.”
She said she knew something had to be done but that no template existed for taking on the problem of restoring Tahoe’s clarity. “When we began our bills, I really didn’t know what was going to work and what wasn’t,” she said. “And so we tried to combine a number of different things [with] lake clarity more or less the guide.”
Balancing environmental needs with those of the economy has always been a challenge in the Tahoe region, as efforts have been geared toward minimizing the footprint of development. “The problem is not growth, we are more than 90 percent built out,” said Jeff Cowen, public information officer for TRPA. “We need to focus on property owners doing more.”
Late last year, TRPA adopted a Regional Plan Update that seeks an all-inclusive approach that raises the bar in terms of controlling nonpoint source pollutants.
“The prescription isn’t the one-size-fits-all anymore,” said Marchetta in an interview with Western Water. “That was the real change, I think, and a beneficial change because it allowed us to scale our view of how do you implement stormwater and erosion control on … 25,000 parcels in the basin.”
In February, the Tahoe Area Sierra Club sued TRPA to block the Plan, saying in its court complaint that the document “revises and loosens the standards by which new projects are reviewed and approved, while increasing the potential for new development throughout the region.”
The Plan “allows local governments to establish environmental standards that do not meet minimum regional requirements, including standards that limit how much land can be paved, or ‘covered,’ to protect natural soil function and prevent runoff into the Lake,” the complaint says.
In a Sept. 1 opinion piece published in The Sacramento Bee, Laurel Ames, conservation co-chair of the Tahoe Area Sierra Club wrote that the Plan “allows more polluted runoff, traffic, smog, pavement and taller buildings – removing the firewall of environmental protection that the standards were intended to provide.”
Ames was responding to the newspaper’s endorsement of the Plan, which it said can reconfigure “old, schlocky, damaging development patterns through infill development.” The Bee said that “the Sierra Club and others, however, do have a real point about the need to strengthen monitoring and enforcement, a weakness of the compact from the beginning.”
TRPA’s Marchetta said the Sierra Club is “an outlier that is misinformed and misguided” regarding the Plan. “They have just simply not offered up anything in the way of a solution,” she said. “All they want to do is stop it.”
The Plan promotes the removal of development from sensitive lands by providing incentives for private restoration, according to Marchetta. “By relocating some buildings from marshes and meadows into town centers, the Plan is projected to eliminate 10,000 vehicle miles traveled annually and an additional 1,200 parcels are expected to be protected or restored,” she said.
This issue of Western Water discusses some of the issues associated with the effort to preserve and restore the clarity of Lake Tahoe.
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So singularly clear was the water, that where it was only twenty or thirty feet deep the bottom was so perfectly distinct that the boat seemed floating in the air! Yes, where it was even eighty feet deep. Every little pebble was distinct, every speckled trout, every hand’s-breadth of sand.
– Mark Twain Roughing It 1861
That Mark Twain quote forever set the clarity of the lake in the public mind. And now the fate of the jewel – Lake Tahoe – is back in the national attention as stakeholders gathered recently from far distant places to discuss the future of Lake Tahoe at the annual Summit. This meeting brought back memories of the first Tahoe Summit – one attended by both President Clinton and Vice President Gore 16 years ago. I remember covering that Summit for the Foundation. That gathering brought national attention to the declining clarity of the lake. As judged by a white plate lowered into the water to test clearness – a Secchi Disk – the clarity had dropped 22 feet by the time of the 1997 Summit. At the first Summit, both President Clinton and Vice President Gore went out on the lake in a small boat with U.C. Davis Professor Charles Goldman to lower the Secchi Disk. That boat trip could not happen today after the events of 9/11 – a president and vice president alone together in a little boat in the middle of a large lake! That would be too much of a security risk.
In this magazine, Writer Gary Pitzer details many of the factors since 1997 that have improved lake clarity about 10 feet. It turns out that Lake Tahoe is resilient. It survived the great silver rush in Nevada during Twain’s time and the resulting sediment pouring into the lake when the surrounding great forests were logged. More than a century of development around the lake followed and again negatively affected clarity. Now regulations and projects are improving the clarity. But disagreement on how to proceed continues and is detailed in this issue of Western Water.