
Through the Forum’s Cooperative Monitoring Program, the U.S. Geological Survey (USGS) conducts water quality sampling, with analyses completed by the USGS National Water Quality Laboratory, Fort Collins Water Quality Laboratory, and Loveland Water Quality Laboratory. The Northern Colorado Water Conservancy District (Northern Water) also conducts monitoring in the C-BT system canals on the East and West Slopes using various water quality laboratories and provides these data to the Forum.
The Forum’s Cooperative Monitoring Program is designed to meet three main objectives:
- Assess the degree of compliance with water quality or stream standards and classifications and/or screening thresholds for streams and lakes/reservoirs (where applicable) related to the beneficial and designated uses of water in the watershed
- Assess the impact of feeder canal and ditch system sources on the Big Thompson River and its tributaries and lakes and reservoirs in the watershed
- Assess the magnitude and statistical significance of temporal and spatial trends in ambient surface water quality constituents for concentrations and mass loadings at select flowing monitoring sites in the Big Thompson Watershed

In 2017, water samples are being collected and analyzed from 15 sites within the Big Thompson Watershed, including the Big Thompson River, North Fork of the Big Thompson River, Buckhorn Creek, East Portal at the Adams Tunnel, and Olympus Tunnel at Estes Park. CB-T canal sites are sampled by Northern Water.
More than 30 parameters are collected at each site, including nutrients, chlorophyll a, metals, bacteria, total organic carbon, total suspended solids, major ions, and physical parameters. Water quality samples are collected monthly from February to November at flowing water sites.
Additional Reports:
- USGS Water Data and current conditions for the Big Thompson River.
- USGS Water Quality Summary, Big Thompson River Basin