Lake Tahoe 2023 winter clarity was best in 40 years, UC Davis report finds
LAKE TAHOE — Lake Tahoe's crystal clear waters continue to improve during the winter months, according to a report from UC Davis.
"Basically, the clarity restoration plan for Tahoe is working," Jeff Cowen, spokesperson for the Tahoe Regional Planning Agency, said.
Cowen said the Clarity Report from UC Davis for 2023 found that winter lake conditions were the clearest observed since 1983.
"It's the kind of trend we've been seeing more and more, [which is] that winter clarity, when there isn't a lot of warmth and growth and activity in the lake as far as the biologic side, is getting better," Cowen said.
However, he said the summer months tell a much different story, marking the fifth murkiest on record.
"The annual average is staying about flat which is still kind of positive considering from the 1970's to the 1990's we were losing about a foot of clarity per year," Cowen said.
Alex Forrest, the interim director at the Tahoe Environmental Research Center, said that when you compare 2022 and 2023, not much has changed.
He said they look at phytoplankton, which are small microorganisms that live in the water.
"Their populations are shifting because they're having warmer temperatures, so they can grow for longer and they can also grow denser because of that, so overall that's attributing to the clarity of the lake," Forrest said.
He said another factor is that during the 2022-2023 winter, Northern California had a large snowpack that caused quite a bit of runoff.
"That is carrying in a lot of particles which contribute to the decrease in clarity," Forrest said.
Cowen and Forrest said the clarity is just one piece of the puzzle when measuring the health of the lake which is why it's so important to help keep it clear.
"Any time people come up to Tahoe, you really need to be thinking about clean, drain and dry watercraft so that we're not spreading aquatic invasive species and always take better care of the lake. Leave the lake better than how you found it," Cowen said.
Forrest said the State of the Lake report should be released sometime next week.