How winter plays important role in keeping Lake Tahoe blue
LAKE TAHOE — Keep Tahoe Blue is more than just a slogan for researchers at UC Davis Tahoe Environmental Research Center (TERC) who are tasked with taking regular surveys of water clarity and the health of Lake Tahoe.
TERC staff research associate Brandon Berry is part of the team that launches those regular research surveys out on the lake, conducting what he describes as a "health check-up."
Berry said winter is a very important time of year for Tahoe.
"When you get a big rain or snow event, that's important because it ends up washing and flushing a lot of the sediment from the watershed into the lake, which can affect clarity through particles getting pushed into the lake," Berry said.
Their most recent survey was taken just days before the first strong winter storm of the season. Cold temperatures from winter weather play an important role in keeping ecosystems healthy throughout Tahoe with a process called mixing.
"It's an important phenomenon that goes on in the lake. Essentially, what you need is just a cold event, and then a wind will come through and mix the entire lake," Berry said. "It mixes the whole body of water and it redistributes oxygen and nutrients throughout the lake."
Lake Tahoe's clarity report from 2023 shows a mix of severe highs and lows. UC Davis researchers found last winter was one of the clearest observed in the lake since 1983. The summer months tell a very different story as it was recorded as the third murkiest in history.
"That's what we're doing out on our monthly monitoring is collecting data related to water quality, but also biological systems, chemical systems, physical systems of the lake," Berry said.
Most of the water samples from surveys are taken from the middle of the lake, but researchers know how important data is closer to the shore where most people recreate. As Lake Tahoe becomes more popular, microplastics entering the water is what advocates hope they can stop before they negatively impact the health of the water.
"It's great that people want to come up and see what a beautiful place it is, when they're doing that I would urge them to, you know be respectful, be good humans," Berry said.
Other things influencing the water's overall health and clarity are climate change and invasive species entering on people's boats.
