Watershed Reports

Below are links to important Watershed Reports in Valley County including water quality monitoring reports:

2026 West Mountain Area Onsite Wastewater System Report

Idaho Statutes Pertaining to Canals and Laterals (2026)

North Fork Payette River Watershed Coalition Watershed 2025 Assessment and Action Plan

2023-2024 Lake Cascade Monitoring Report (published January 2026)

2022 DEQ TMDL & 5-Year Review Overview | Idaho Department of Environmental Quality GIS Open Data

2022 Valley County Ground Water Quality Improvement and Drinking Water Source Protection Plan: Multi-agency report 

2019 Monitoring Report Cascade Reservoir and the North Fork Payette River

2018 DEQ TMDL & 5-Year Review Idaho Department of Environmental Quality

2011 Cascade Reservoir Tributary TMDL Addendum

2000 Implementation Plan: Implementation Plan for the Cascade Reservoir Phase ll Watershed Management Plan.

2005 Valley County South Lake Sewer Facilities Planning Study: Keller and Associates 2005 Valley County South Lake Sewer Facilities Planning Study

1989 West Mountain Privy Report: Central District Health South Lake Recreational Water and Sewer West Mountain Area Southern Portion Privy Report