Eagle River: Gore Creek to Avon WWTP

Current and Historical Drivers of Degradation

Although this segment is not listed as an impaired waterway by Colorado’s Water Quality Control Division, macroinvertebrate health indices in Avon hover only slightly above the state of Colorado’s impairment threshold and are consistently lower than Eagle River sites both upstream and downstream. Indices of sensitive taxa presence are the lowest of anywhere on the mainstem Eagle River, indicating impacted water quality conditions. Pollutants likely source locally from urban runoff in the vicinity of Avon, and disruption or degradation of the river’s riparian buffer corridor is also likely to play a role.

The frequency of peak flows equivalent to the natural 1-in-4 year flood declined nearly 60% due to upstream water use and management. Peak flows during dry years declined 21% and total annual volumes declined 22% when compared to natural historic conditions.

Report Card