Lake Tahoe’s water clarity is no longer declining, according to researchers who’ve been tracking the lake’s water quality for at least two decades. In 2021, the lake’s water clarity measured 61 feet.
Officials at the Nevada Department of Environmental Protection are part of a multi-agency, bi-state team that’s been monitoring and working to restore Lake Tahoe’s water quality. The team released a report this week that identified fine sediment as among the top pollutants threatening the lake’s water quality.
In 2021 fine sediment pollution in the lake was reduced by nearly 600,000 pounds — about the same mass as 206 cars — an increase over the 2020 reduction of 523,000 pounds.
Efforts to reduce this fine sediment pollution include reducing urban stormwater pollution and preventing other pollutants from reaching Tahoe’s waters. Experts say their work has also reduced both nitrogen and phosphorous in the lake, which both contribute to algae growth.
Mike Plaziak is executive officer of the Lahontan Water Board and a member of the Lake Tahoe Total Maximum Daily Load (TMDL) program. He said maintaining the lake’s clarity is about more than just the water in the lake.
“Our program’s efforts have become even more critical as Lake Tahoe faces other water clarity challenges from wildfire, smoke, and climate change,” Plaziak said. “Going forward, restoring lake clarity will require us to continue our close coordination and implementation of best practices at every level, from how we maintain roads to how we gather data and adapt our strategies to manage climate impacts.”
The ultimate goal of the TMDL program is to, the “Clarity Challenge” goal, is to improve Lake Tahoe’s water clarity to 78 feet by the end of 2031 and eventually return water clarity to up to 100 feet.
Researchers and environmentalists at other agencies are tackling Lake Tahoe’s clarity as well.
In 2021 researchers from the Tahoe Science Advisory Council and Tahoe Environmental Research Center looked at how wildfires such as the Caldor Fire impacted small particle pollution in Lake Tahoe. Scientists at Desert Research Institute are also looking at how micro plastics pollution impacts the lake’s water quality and clarity.
To read the full report from the TMDL program and learn more about Lake Tahoe’s clarity visit https://clarity.laketahoeinfo.org/.
Source: Nevada Division of Environmental Protection
