Project Sponsor
Coeur d’Alene Tribe
Purpose
This project evaluates phosphorus loading from streams and rivers that discharge into the southern end of Coeur d’Alene Lake. The information obtained will set priorities for future nutrient reduction efforts.
The Coeur d’Alene Tribe is leading this study, based on a recommendation from the 2022 National Academies of Sciences report. The study will be conducted over two years and include 35 monitoring locations in the St. Joe and St. Maries River basins and Benewah, Lake, and Plummer Creeks. Together, these water bodies contribute an estimated 80 tons of phosphorus into the lake each year, accounting for almost 40% of the total phosphorus load.
Funding
This project received $1.2 million from Governor Little’s Leading Idaho initiative.
Current Status
Monitoring began in spring 2024 and wrapped up in spring 2026, with final measurements occurring summer 2026. Data collected included discharge measurements, water chemistry samples, and continuous water-level monitoring. Data organization and analysis are ongoing and a report is underway, with a final report anticipated in fall 2026.
Outcome
After completing the study, the Coeur d’Alene Tribe will develop a nutrient management action plan for these watersheds. A final report on nutrient loading is expected in late 2026.