In 2022, for the first time in its history, herbicides were discharged into the waters of Lake Tahoe, one of the world’s most protected and pristine lakes. The public was told this was a “test” to manage aquatic invasive weeds in the Tahoe Keys, but a California court has since ruled otherwise. This was not a “test,” it was an illegal discharge of chemicals into Lake Tahoe’s waters.

The Sierra Club and California Sportfishing Protection Alliance (CSPA) sued the Lahontan Regional Water Quality Control Board for granting an illegal exemption to its own rules prohibiting pesticide discharges. In a definitive ruling issued last year, the Court ruled that Lahontan had violated the Basin Plan and “abused its discretion” in granting the permit. It ordered Lahontan to revoke (nullify) the herbicide permit and all its decisions, including all environmental documents associated with the Project.

Yet in recent months, articles and public presentations have reframed this illegal action as a success story, ignoring the court’s ruling entirely. This revisionist narrative is not only misleading, it is dangerous.

The Tahoe Regional Planning Agency (TRPA), the League to Save Lake Tahoe, and the Tahoe Keys Property Owners Association (TKPOA) are sweeping the lawsuit under the rug. TRPA and the League not only supported the herbicide plan from the beginning, but were instrumental in pushing it forward. According to a credible source present during internal agency discussions, the TRPA’s Executive Director instructed Lahontan’s Executive Officer to “get this done,” strongly urging approval of the herbicide permit, which directly conflicted with existing environmental protections.

At no point have any of these organizations admitted wrongdoing. Instead, they continue to publicly celebrate the illegal discharge while downplaying or ignoring its very real failures: excessive herbicide retention and massive cyanobacteria blooms of harmful algae.

Let’s not forget: Lake Tahoe is a designated Tier 3 Outstanding National Resource Water, the highest level of protection under the Clean Water Act. This designation prohibits long-term degradation of water quality, which the discharge of chemicals like Triclopyr and Endothall certainly represents.

While the law clearly requires agencies to prove that non-chemical methods are infeasible before resorting to herbicides, that step was skipped. Non-chemical options for controlling aquatic invasive species have been and continue to be downplayed – most often by TKPOA’s paid consultants, who have vested interests in promoting chemical solutions.

Equally disturbing is the manner in which public engagement has been managed. At a TRPA “listening session” held on July 18, 2025, most of the time was devoted to presentations from TRPA, TKPOA, the League, and their partners—all of which praised the results of the illegal discharge investigation. Public questions had to be submitted in advance and were never read aloud or answered directly. The format offered no real interaction, no visibility of other attendees, and no opportunity for dissent. This isn’t public transparency. It’s public theater.

The Sierra Club submitted six critical questions ahead of that session, none of which received a clear response. These questions are fundamental to any honest conversation about the future of Lake Tahoe’s waters:

1. Will TKPOA apply for another herbicide permit, despite the lawsuit ruling and failure to prove that non-chemical methods are ineffective?
2. Given the warm, stagnant, nutrient-rich nature of the Keys lagoons, what long-term plan exists to address these root causes?
3. Has TKPOA committed to upgrading the lagoons’ circulation and filtration system? If not, why not?
4. Why haven’t fertilizers been banned within the Keys and other nearshore areas of Lake Tahoe?
5. Shouldn’t invasive species management protect all beneficial uses of Lake Tahoe, not just boating and recreation?
6. Do the results show that non-chemical methods are infeasible—and if so, where is that evidence?

These are not rhetorical questions. They are calls for accountability—backed by legal precedent, public interest, and ecological urgency.

It’s time for TRPA, Lahontan, TKPOA, and the League to come clean. They must acknowledge the court’s ruling, abandon plans for further herbicide use, and commit to transparent, science-based, non-chemical management strategies. Lake Tahoe is too rare, too fragile, and too important to be a testing ground for failed pesticide policies.

We don’t need greenwashing. We need the truth—and we need it now.

Tobi Tyler, MS Environmental Engineer, UC Berkeley; Vice Chair and Conservation Chair of Sierra Club’s Tahoe Area Group, and Lake Tahoe resident and conservation advocate