by Lisa Wallace, Executive Director
At first glance, the Truckee River and its tributaries look pristine but in fact they are classified as impaired (polluted) from excessive sediment levels (Total Maximum Daily Load for Sediment – Middle Truckee River Watershed, U.S. EPA and California Regional Water Quality Control Board, Lahontan Region, 2008).
The Truckee River Watershed Council has a robust monitoring program for the Truckee River. The monitoring data focuses on the relationship between the biological conditions, or the living components in the ecosystem, and sediment deposition.
Monitoring results show significant problems in biological conditions starting with sediment coverage of only 20%! There are two sets of problems: 1) a decrease in both the quantity and quality of aquatic insects, and 2) a shift toward aquatic insects tolerant of poor water quality. At 80% or greater sediment coverage, there are significant decreases in the biological condition within the Truckee River and its tributaries.
What does this mean for our watershed?
The monitoring results show the River is experiencing increased sedimentation and this is causing the loss of aquatic insects. These bugs are the base of the food web – they are food for larger species such as fish. When the insects are degraded, the food source for the fish is degraded. Sources of sedimentation are from poor land uses in all parts of the watershed. Run-off from roads, trails, yards, forests, ranches, business, and homes — they all increase sedimentation in the Truckee River.
Each one of us can make a difference: Our Adopt-A-Stream water quality monitoring program needs volunteers. Homeowners can reduce the negative impacts of erosion and sedimentation by joining River-Friendly Landscaping.
These programs along with our restoration projects work to reduce sedimentation and restore our watershed so that we can have a biologically rich and resilient ecosystem.
Thank you to the donors of the Truckee River Watershed Council, the California Natural Resources Agency, and the Lahontan Community Foundation for supporting our water quality monitoring programs.
Photo: A volunteer collects a water sample at Pole Creek. Credit: Stefan McLeod