For immediate release:
August 16, 2022
Dimitri Stanich, National Water Resources Control Board
Samantha Thompson, NV Environmental Protection Division
LAKE TAHOE, NV/CA – According to a bi-state report released today by the Nevada Division of Environmental Protection (NDEP) and the Lahontan Regional Water Quality Control Board, part of the Environmental Protection Agency from California.
Notably, the 10-year performance report of the bi-state Lake Tahoe Total Maximum Daily Loading (TMDL) program shows that fine sediment pollution, which significantly impairs lake clarity, has been reduced by nearly 600,000 pounds in 2021, the mass equivalent of about 206 cars. This is an increase from last year’s reduction of 523,000 pounds. Nitrogen and phosphorus, both of which contribute to algae growth, have also been reduced by thousands of pounds per year through the program, thanks to the efforts of federal, state and local agencies, as well as private landowners in the basin. . The lake’s last level of clarity was measured at a depth of 61 feet.
“Our program’s efforts have become even more critical as Lake Tahoe faces additional water clarity issues related to wildfires, smoke and climate change,” said Mike Plaziak, director. General of the Lahontan Water Board. “Going forward, restoring lake clarity will require us to continue our close coordination and implementation of best practices at all levels, from how we maintain roads to how we collect data and adapt our strategies to manage climate impacts.
The results of the bi-state report revealed that the partnership between local governments as well as transportation agencies in California and Nevada successfully met 10-year goals set to reduce urban stormwater pollution and improve clarity. Lake.
“I am proud of the progress made over the past decade to restore and improve Lake Tahoe’s iconic water clarity,” said NDEP Administrator Greg Lovato. “Going forward, we will continue to work with the Lahontan Water Board, the Tahoe Regional Planning Agency, and Lake Tahoe science and implementation partners to advance science-based strategies and solutions that create a more vibrant, sustainable, and climate-resilient Lake Tahoe.
The Lake Tahoe TMDL Program is a bi-state effort between Nevada and California that was launched in 2011 to restore and improve Lake Tahoe’s water clarity to historic levels by requiring local governments and highway departments to both sides of the lake to implement measures that help prevent pollutants harmful to clarity from reaching the lake. These implementation actions are intended to help Lake Tahoe meet the Clarity Challenge goal of water clarity to at least 78 feet by the end of 2031. Over time, the goal is for people to be able to see again at depths of 100 feet.
The 2022 Performance Report highlights key accomplishments through 2021, the 10th anniversary of the TMDL program, and showcases important projects and actions taken by Lake Tahoe partners to significantly reduce clarity-harming pollutants.
Key findings from the 2022 Performance Report include:
- In 2021, the annual clarity measured 61 feet. However, since clarity can vary widely from year to year depending on climate, lake processes, and other conditions, the long-term trend is considered a more valuable indicator. Over the past 20 years, the clarity of the lake has remained relatively stable and is no longer decreasing.
- Researchers have found that fine particulates and algal chlorophyll are the main variables affecting the clarity of Lake Tahoe. Recent years have presented evolving and new threats to Lake Tahoe, as climate change, rising temperatures, flooding, drought, and wildfires impact the lake in ways not currently seen. not fully understood.
- Wildfires continue to be the main threat to restoring water clarity. The report examines in particular the restoration works completed for the Angora fire, similar to those that should be carried out for the Caldor fire, in order to minimize the impacts on water quality, as well as the studies launched to determine the water quality impacts of smoke, ash and forest fires. and the effectiveness of forest health and fuel reduction projects in minimizing these impacts.
- Analyzes show that efforts to reduce pollutants entering the lake through runoff from forest land, erosion of stream beds and banks, and atmospheric deposition are on track to meet the 10-year goals.
To learn more about the TMDL program and accomplishments to improve Lake Tahoe water clarity, check out the Lake Clarity Tracker.