Volunteer mapping of invasive plants along Upper Truckee River completed

SOUTH LAKE TAHOE, Calif. - A three-year effort to survey the Upper Truckee River for aquatic invasive plants has wrapped up. Community members, supported by staff from the League to Save Lake Tahoe, Tahoe Resource Conservation District, and California State Parks joined together to map the plants in order to prevent their spread during major upcoming restoration projects along the river, Lake Tahoe’s largest tributary.

“Our citizen science volunteers are some of the most passionate Tahoe lovers I have met who are always looking for meaningful ways to Keep Tahoe Blue,” exclaimed Emily Frey, the League’s citizen science program coordinator. “This type of effort allows them to dive deeper into the issues and serve as ad-hoc aquatic biologists…a truly unique and meaningful experience.”

The Upper Truckee River collects runoff from a third of the Lake Tahoe Basin and supports one of the largest wetlands in the Sierra Nevada. Historical logging, grazing, and urban development have degraded the river, and destroyed much of the wetland marsh habitat where the river meets Lake Tahoe. This multi-year survey, conducted through the League’s Eyes on the Lake Program, mapped the location of two aquatic invasive plants: curlyleaf pondweed and Eurasian watermilfoil. These aquatic invasives pose one of the greatest threats to Lake Tahoe’s delicate ecology.

“It’s great to see community members engaged and empowered through citizen science efforts like this,” said Jen Greenberg, associate environmental planner with the California Tahoe Conservancy. “This extensive survey will help inform multi-million dollar restoration projects, including the Upper Truckee Marsh restoration.”

The Conservancy, Tahoe RCD, and California State Parks all have ongoing and future significant restoration projects located along the Upper Truckee River. These projects will help restore the resiliency of the river and its habitat to climate change, while improving water quality flowing downstream to Lake Tahoe.

Eyes on the Lake is the League's volunteer citizen science program to help prevent the spread of aquatic invasive plants in Lake Tahoe and surrounding waters. Trained volunteers identify and report on aquatic invasive plants they find in and around Tahoe, helping to address infestations early while they are easier to control.

Survey participants began their work in 2016, surveying the river from its mouth at Lake Tahoe upstream to its crossing by U.S. Highway 50, mapping multiple significant infestations of both curlyleaf pondweed and Eurasian watermilfoil. In 2018, participants surveyed the next stretch of river, starting from where the 2016 effort ended and concluding at the U.S. Highway 50 / State Route 89 crossing near Elks Club Rd. In 2019, surveyors completed the final upstream reach to the river’s southernmost crossing of U.S. Highway 50 in Meyers. Survey teams found no invasives in either the 2018 or 2019 surveys. Final survey maps and a report were completed by League staff and provided to land managers along the river.

“This type of collaboration between community members and Tahoe agencies can be a very powerful resource,” stated Jesse Patterson, chief strategy officer for the League. “We hope to continue to grow the army of citizen scientists here in Tahoe so we can not only raise awareness about environmental challenges facing our Lake but also provide valuable information for projects on the ground.”

The League invites community members to its Citizen Science Celebration on October 17. The event celebrates Tahoe volunteers and the valuable citizen science work that they do, and attendees can learn more about how to get involved in all the League's citizen science programs. Learn more.

The League’s Eyes on the Lake program has benefited from funds generated by sales of Lake Tahoe license plates. Show your love for Lake Tahoe by purchasing your own Lake Tahoe plate today: tahoeplates.org.