Click to watch on overview of the challenge in the Tahoe Keys.
Tackling Invasive Species to Save Lake Tahoe
As a believer in our mission to Keep Tahoe Blue, you know that aquatic invasive species are the greatest ecological threat to the health of the Lake, as well as our enjoyment of its sparkling blue waters. The Tahoe Keys are ground zero for the infestation of aquatic invasive weeds at Tahoe. To put this threat in check, a proposal to test a suite of control methods is moving through a strict environmental review process.
Watch this video to get the latest update on where we are in the process and the next steps.

The League to Save Lake Tahoe strongly supports this proposed “Control Methods Test” because science clearly shows that aquatic weeds pose a dire threat, the status quo will not solve the problem, and the fate of Lake Tahoe is at stake. Read more about the problem below, and learn how you can weigh in on the proposed test.

Get up to speed on the Tahoe Keys weeds situation by attending an open house hosted by the Tahoe Keys Property Owners Association on October 29.
OPEN HOUSE - Tackling Weeds in the Tahoe Keys
WHEN: Drop in, 3 - 6pm | Friday, Oct 29
WHERE: Tahoe Keys Pavilion, 356 Ala Wai Boulevard, South Lake Tahoe
The Tahoe Keys Weeds Control Methods Test
The Control Methods Test is a proposal to test a suite of proven technologies from around the world, along with emerging methods and new combinations of these treatments including ultraviolet light, laminar flow aeration, and a one-time, targeted use of herbicides. 

The League does not take the use of herbicides in the Lake lightly. We support the Control Methods Test in part because it is exactly that, an exhaustively planned, highly controlled, rigorously monitored, one-time test that can show us how to save Lake Tahoe. To Keep Tahoe Blue, we must move forward with this comprehensive and careful test of any and all safe methods that could be part of the long-term solution. 
Murky, weed-choked shorelines, neon green water, and toxic algae blooms are not part of the Tahoe we know and love. But even today, that horror story is reality in some parts of the Lake, due in part to aquatic invasive weeds. Unless we act now, no stretch of Tahoe’s 72-mile shoreline will be safe from that same, ugly fate. The Control Methods Test is the crucial, next step.
An infestation of aquatic weeds encourages a hazardous algal bloom in the Tahoe Keys
A toxic algae bloom and aquatic weeds in the Tahoe Keys.
The League Supports the Control Methods Test
The League’s efforts to Keep Tahoe Blue are always guided by the best available science. Here are some of our key reasons for supporting the test.
  • Immediate action is required to stop the infestation in the Tahoe Keys lagoons from growing, spreading to other areas of the Lake, degrading water quality, and harming recreational opportunities.

  • The project's environmental studies conclude that taking no action, or continuing what's being done now, will result in the most harmful outcome for the Lake.

  • The tools we have now are not sufficient to tackle the complexity and scale of the Tahoe Keys lagoons infestation – a unique and innovative solution is needed.

  • Past experience shows that there is no silver bullet. We need to test all tools – proven and innovative – to find the optimal combination for safe, sustainable, long-term treatment. 

  • A step-wise test of each possible treatment will take far too long. By that time, the problem will have spread considerably.

  • We support the rigorous, science-based approach to testing and monitoring all potential control methods as a cohesive three-year program which would result in no long-term degradation of Lake Tahoe's water quality.

  • Lahontan Water Quality Control Board staff concludes in the Tentative Waste Discharge Requirements and Draft NPDES Permit that "water quality changes in the ONRW (Outstanding National Resource Water) will be short-term and temporary, will not permanently degrade water quality, and will protect the existing uses in the ONRW. Therefore, the water quality of the ONRW is maintained and protected" (pg. 118 of 118).

  • The Control Methods Test is a thoroughly vetted, time-limited test; it is not a full-scale, long-term program.

  • The Control Methods Test would apply herbicides in lower concentrations than what is allowed by EPA. Also, there would only be one application of herbicides – not ongoing applications. The proposal is very clear on this.

  • The Tahoe Science Advisory Council – an independent group of Tahoe scientists from California, Nevada and federal agencies – peer-reviewed the proposal and concluded that monitoring procedures for the test are "scientifically rigorous," and that the "monitoring methods are sound."
Submit a Comment - Have Your Voice Heard
As part of the environmental review process for the Control Methods Test, the Lahontan Water Quality Control Board is seeking public input on draft documents for the test. You can submit your comments until 5 pm on Monday, November 1 by emailing with the subject line “Tahoe Keys Weeds Control Test.”

Weeds harvested from the Tahoe Keys. Photo: TKPOA
About the Invasive Weeds Problem in the Tahoe Keys
The Keys are ground zero for the infestation of aquatic weeds at Tahoe, and the problem is spreading. More than 100 acres of the Lake itself are now infested. Despite millions of dollars already spent by the Tahoe Keys Property Owners Association (TKPOA), the tools on hand are not sufficient to treat a problem as big and complex as in the Keys. So we need to try something different to Keep Tahoe Blue.

For the last nine years, the League to Save Lake Tahoe has been deeply involved in efforts with the TKPOA, Tahoe Resource Conservation District, Lahontan Water Quality Control Board and Tahoe Regional Planning Agency to control Tahoe’s aquatic weed problem where it’s most severe: the Tahoe Keys, a planned community on the south shore developed in the 1960s. 

With a consistent, credible voice, the League has collaborated, innovated and funded cutting-edge treatments for the invasive weeds problem in the Keys. These efforts have been effective stop-gap measures, but greater action is needed to stop the problem from spreading and keep it under control. 

Learn more about our efforts to tackle the problem inside the Keys and in the Lake itself. And read our CEO’s opinion columns published in the Tahoe Daily Tribune and Reno Gazette Journal.
Share this eNewsletter.
League to Save Lake Tahoe | 530.541.5388 |