Lake George dam project monitoring efforts continue following the dam’s removal

The obsolete Lake George diversion dam on the South Platte River has been removed, and restoration and monitoring efforts are underway. Before its removal, the low-head diversion structure affected the river by impeding the natural movement of sediment, modifying the structure of the floodplain and channel, negatively affecting fish habitat, and jeopardizing fish reproduction and survival. Removal of the dam restores a popular sport fishing segment on the river to a more natural condition and improves local aquatic habitat and water quality of approximately 45 river miles of the South Platte River from Eleven Mile Reservoir to Cheesman Reservoir.

Photo Credit

Erika Reiter

Researchers at the Rocky Mountain Research Station, Charlie Shobe (right, orange hardhat), Research Geomorphologist, and George Valentine (center, white hardhat), Ecologist, are joined by Virgil Alfred (left, blue life jacket), student in the lab of Katherine Lininger at University of Colorado Boulder, and Laura Bugyi (center, brown baseball cap), wildlife technician with the Pike-San Isabel National Forests & Cimarron and Comanche National Grasslands, as they measure characteristics of the streambed to understand how the channel has changed since the dam's removal.  

A cadre of scientists visited the project site at the end of April 2024 to continue monitoring efforts that began before the dam’s removal. The team comprised of members from the USDA Forest Service Rocky Mountain Research Station, the South Park Ranger District on the Pike-San Isabel National Forests & Cimarron and Comanche National Grasslands, and the University of Colorado Boulder. Researchers used GPS to survey the shape of the river channel and collected sediment samples to determine the quality of habitat on the riverbed.  This research will help scientists understand how river shape and aquatic ecosystem composition change after dam removal in steep mountain rivers. Monitoring will continue through at least 2025.

The dam at Lake George was constructed in 1952 by Colorado Springs Utilities. The utility operated and maintained the diversion dam for municipal water supply to reservoirs on the Pikes Peak Ranger District until the early 1990s at which time the point of diversion for the utility’s water rights was moved to another location; however, the dam was left in place until its removal in 2023.

The removal, restoration, and monitoring are part of a collaboration among the Rocky Mountain Research Station, the Pike-San Isabel National Forests & Cimarron and Comanche National Grasslands, the Coalition for the Upper South Platte, Colorado Parks and Wildlife, Colorado Department of Natural Resources Water Resources, the South Platte Enhancement Board, Park County and its Land and Water Trust Fund, Trout Unlimited, Denver Water, Aurora Water, and Colorado Springs Utilities.