Truckee River Aquatic Plant Control Project


Tahoe Resource Conservation District (Tahoe RCD)




Innovation Applied to Tackle Invasive Plants in Truckee River

Truckee River, Tahoe City, CA – The Tahoe Resource Conservation District (Tahoe RCD) has piloted a project on the Truckee River to control the aquatic invasive plant, Eurasian watermilfoil (Myriophyllum spicatum), which has been growing in Lake Tahoe since the late 1980s, and likely entered the Truckee River following the overflow of the dam in 1997.

Tahoe RCD is a leader in developing highly-effective control strategies for open-water aquatic plant removal in collaboration with the Lake Tahoe Aquatic Invasive Species Program. In 2010, approximately 6 acres of aquatic invasive plants covered the nearshore near Vikingsholm in the iconic Emerald Bay. Control strategies used in Emerald Bay included laying down bottom barriers to kill the plants by eliminating light, and using diver-assisted suction removal to physically remove plants and roots. After four years of comprehensive treatment, Emerald Bay is free of aquatic invasive plants.

Tahoe RCD is now taking this strategic deployment of both methods to the Truckee River, from the lakeside of the Tahoe City Dam downstream to Alpine Meadows Road. Eurasian watermilfoil is growing in large dense patches along this stretch of the river. These patches of vegetation can alter water quality by raising pH, decreasing oxygen, and increasing water temperature, as well as causing a decrease in water clarity, all of which ultimately alters the ecosystem and causes negative impacts to recreation and public safety.

In 2014, 10,000 square feet of benthic bottom barriers were laid lake-ward of the Tahoe City Dam. In 2015, fewer than twenty plants have been detected at this site and subsequently removed. Also in 2014, 427 cubic feet of invasive plants were removed downstream from the dam using diver-assisted suction removal. In August of 2015, Tahoe RCD is working with A.C.E. Diving to install bottom barriers in the river system below the dam the same team successfully treated the Eurasian watermilfoil infestation at Emerald Bay. While bottom barriers have been successful in open water lake environments, using them within a river system will be a new application of this method.

“With the drought conditions, many people have asked how the lack of water at the Dam and down the Truckee River will impact efforts to remove invasive plants,” said Kim Boyd, District Manager at Tahoe RCD. “With the low waters this creates a unique opportunity to use bottom barriers which provides a cost-effective technique for plant removal.”

Tahoe RCD anticipates the need to continue efforts to control aquatic plants in the Truckee River for several years to come as the population is dense in some locations and environmental conditions such as water levels will continue to fluctuate.

“From our efforts in Emerald Bay, we know that invasive plant populations can be reduced and with continued treatments we will be able to better manage the populations in the future.” Boyd continues.

Funding for this project has been provided by the Community Foundation of Western Nevada/Truckee River Fund, California Department of Parks and Recreation, the Tahoe Fund, and the Rotary Club of Tahoe City.

About the Tahoe Resource Conservation District

The Tahoe Resource Conservation District’s mission is to promote the conservation and improvement of the Lake Tahoe Basin’s soil, water and related natural resources by providing leadership, information, programs, and technical assistance to all land managers, owners, organizations, and residents. The Tahoe RCD is a non-regulatory, grant-funded, public agency that works with a variety of partner agencies to implement projects, programs and outreach which currently focus on erosion control, runoff infiltration, terrestrial and aquatic invasive species control, and conservation landscaping.

Press Contact:
Nicole Cartwright
Tahoe Resource Conservation District (Tahoe RCD)
530.543.1501 x111