Sediment Fingerprinting in the Upper Klamath Basin

Science Center Objects

Sediment fingerprinting has been used successfully to identify land uses that are the major sources of sediment. This study will apply these techniques in a predominantly rural, volcanic landscape.

Rivers deliver nutrient-enriched sediment to Upper Klamath Lake. High nutrient concentrations, most notably phosphorous, trigger expansive and sometimes toxic algal blooms every year in the lake. The Oregon Department of Environmental Quality has set a Total Maximum Daily Load (TMDL) that requires a sharp reduction in phosphorous concentrations. Action agencies and residents and agencies are considering significant investments to restore the upper Klamath Basin.

Reducing erosion in upstream watersheds reduces suspended sediment and nutrient concentrations flowing into the lake, and also improves stream habitat quality in the tributary watersheds. These watersheds support native fish that are critical to the survival and prosperity of the communities and tribes in the Upper Klamath Basin.

Understanding the sources and dynamics of suspended sediment informs decisions about restoration activities. With more complete knowledge, parties can prioritize restoration efforts, both geographically and temporally, to maximize impact with minimum investment and disruption. This understanding, coupled with sediment monitoring, also provides a means to determine the efficacy of implemented restoration activities over time.