Lake Tahoe Clarity Improved By 10 Feet In 2018 After Setting Record Low The Year Before

Lake Tahoe's clarity improved by more than 10 feet last year, according to the latest measurements by the UC Davis Tahoe Environmental Research Center.

Lake clarity increased to 70.9 feet in 2018, after dropping to an all-time low of 60.4 feet in 2017. Experts say the low clarity in 2017 was due to record snow and rain pushing sediment built up during the drought into the lake.

Jesse Patterson, Chief Strategy Officer for the League to Save Lake Tahoe, said he's encouraged by the improvement, but they must continue to restore meadows and marshes that act as natural pollution filters.

"Because it looks like weather and climate are going to keep fluctuating in these extremes and we might see more pulses of pollution like we saw in that 2017 year, and the lake has to be ready for that," Patterson said.

Average annual Lake Tahoe Secchi depth measurements.UC Davis Tahoe Environmental Research Center

Patterson says visitors to Lake Tahoe can help out by going to one of Keep Tahoe Blue's restoration or litter clean up events or just by getting out of their car.

"And the League to Save Lake Tahoe is helping to advocate for back paths and easier bike access and better buses and transit so you can do that," he said.

The Tahoe Science Advisory Council, of which UC Davis is a partner, is finalizing a Science to Action Plan to assess climate change impacts on lake clarity and ecological processes.

“Research shows Lake Tahoe and other inland water bodies are warming faster than the oceans and atmosphere,” Joanne S. Marchetta, executive director of the Tahoe Regional Planning Agency, said in a statement. “Seasonal weather extremes will most likely drive greater swings in clarity from year to year in the future, so it’s imperative we continue to invest in the lake’s restoration to combat new and emerging threats.”

The UC Davis Tahoe Environmental Research Center has been tracking the Lake's clarity since 1968.