Annual Hydrodam Sediment Release Starts Tonight

Be aware of reasons for Uncompahgre River color change

To allow the Ouray Hydroelectric Plant to continue operating, the hydrodam reservoir will release water full of sediment for approximately one week, starting Friday, April 14 at 7 p.m. This release into the Uncompahgre River upstream from the Ouray Ice Park happens each spring as annual maintenance. Since high spring snowmelt and runoff is already flushing sediment through the river, the additional sediment may not be very noticeable.

The sediment is not something created by the dam. It is constantly traveling through the Uncompahgre River naturally. If the dam did not exist, the sediment would be released over a longer period of time as the river ebbs and flows. The dam release allows the built-up sediment from the past year to move out of it rapidly over a shorter time period, but does not affect the overall quantity of sediment moved. Conservatively, the sediment release accounts for less than one percent of the annual sediment load of the Uncompahgre River.

Based on water quality data collected before, during and after the 2017 and 2019 sediment releases, the sediment releases change water quality for a very brief period. When compared to River Watch data collected from the Uncompahgre River in Ouray and in Ridgway at County Road 24 over the past decade, metal concentrations measured during the release were not greater than the concentrations observed during runoff for most metals.

Read about the Ouray Hydrodam Sediment Release Study