The Nez Perce Soil and Water Conservation District (NPSWCD) received funding from the USDA Natural Resources Conservation Service National Water Quality Inventive Program (NWQI) to complete watershed assessments on 49,438 acres of land within five small streams within Nez Perce County, Idaho.
These streams include Tammany Creek (22,225 acres), Ten-Mile Creek (8,867 acres), Hidden Creek (4,131 acres), Lindsay Creek (14,215 acres), and a small unnamed tributary (299 acres) within the NPSWCD boundaries.
These streams do not meet water quality standards. In addition, two of these streams have Total Maximum Daily Load (TMDL) allocations developed for the identified pollutants (Tammany and Lindsay Creeks).
A TMDL assessment for Tammany Creek was completed by Idaho Department of Environmental Quality (Idaho DEQ) in 2001 and amended in 2010. The pollutants of concern are sediment, total phosphorus, nitrite plus nitrate, and E. coli.
A TMDL assessment for Lindsay Creek was developed by Idaho DEQ in 2007 and named bacteria, excess nutrients, and sediment as the pollutants of concern. The TMDLs have been approved by USEPA.
The assessment will likely find that agricultural best management practices can reduce degradation of water quality by these pollutants.
Idaho DEQ delineated 14,060 acres of source water protection area in the Lindsay Creek, Tammany Creek and Hidden Creek watersheds. Idaho DEQ also delineated 50,300 acres of Nitrate Priority Area in the Lindsay Creek and Tammany Creek watersheds where nitrates in groundwater are elevated and of concern. Implementation of agricultural BMPs will help protect sources of drinking water.
Objective 1: Identify water quality pollutants within study area.
Objective 2: Develop treatment alternatives to address identified pollutants.
Objective 3: Conduct public outreach activities to solicit voluntary participation in NWQI phase II implementation project.
As assessment products are developed they will be published on this web site.
Tammany Creek – Under development
Lindsay Creek – Under development
Hidden Creek – Under development