Wildlife
The Chimney Hollow valley is home to multiple species including elk, mule deer, black bear, mountain lion, coyote, fox and special status golden eagles. The Colorado River headwaters provide habitat for a similarly diverse variety of wildlife species. Maintaining and even improving the wildlife habitat around Chimney Hollow Reservoir is critical for various species to survive and thrive, both during and following construction.
“We are excited that through the Chimney Hollow Project, we have partnered with Larimer County to establish a new approximately 3,400 acre protected open space that will preserve native wildlife habitat for present and future generations. Also, we are in the process of collaborating with Colorado Parks and Wildlife on habitat enhancement projects around the reservoir site,” said Sean Henry, the Environmental Planning Department Manager at Northern Water.
As part of the project’s mitigation enhancements, the Subdistrict has committed to several measures to enhance aquatic habitat. We participate in the Upper Colorado River Endangered Fish Recovery Program to recover and protect several endangered native fish species and to enhance the Colorado River’s aquatic habitat. We’re also actively working on the Colorado River Connectivity Channel which will construct a connecting channel around Windy Gap Reservoir capable of passing water, fish and sediment, thereby reconnecting miles of the Upper Colorado and Fraser rivers. Additional projects include stream restoration on the Colorado River between Windy Gap and Williams Fork, and providing Windy Gap water to the Middle Park Conservation District and Grand County to improve river flows.
Vegetation and Plants
Another environmental priority at Chimney Hollow is maintaining vegetation wherever possible to protect and enhance wildlife habitat. Wetlands are regulated under the Clean Water Act and federally-listed plant species are protected under the Endangered Species Act. Additionally, Colorado monitors plant species through the state’s Natural Heritage Program.
“We try to minimize removal of native vegetation to conserve the aesthetic, ecological and cultural characteristics of the space,” Henry said. Maintaining plants and vegetation throughout the valley and along water transmission pipelines helps protect the environment. However, new reservoir construction does require some clearing to construct the project’s key components. Henry, along with Cassie Funke, a project engineer with Barnard Construction Company (the general contractor) who oversees environmental impacts, are working in close partnership to minimize clearing and protect trees, plants and other vegetation.
Water Quality
The Chimney Hollow Reservoir Project’s environmental stewardship also involves protecting and enhancing Colorado River water quality, including efforts to finalize a nutrient reduction plan for Lake Granby, Grand Lake and Shadow Mountain Reservoir and Grand County.
“The most challenging piece is to figure out how to not increase nutrients in the Three Lakes, while increasing pumping from Windy Gap Reservoir to Chimney Hollow Reservoir,” he said. The Subdistrict has made a commitment to not increase nutrients into the Three Lakes as part of the Chimney Hollow Reservoir Project’s federal permit.
The Subdistrict also monitors water temperature in the Colorado River and is working diligently to meet water temperatures goals during peak flow seasons.
Cultural Resources
Reservoir construction also required a historical review and survey of the valley’s cultural resources.
“We combed the entire floor of the valley to look for historic and pre-historic resources in the area,” Henry said. As a result of those findings, they were careful to design reservoir components around those significant resources, such as designing the saddle dam road to go around a stacked rock wall to leave it undisturbed.
A full-time on-site archeologist continues to monitor the project to ensure that work avoids any areas with identified pre-historic or cultural resources.
Partners in the Project
The Subdistrict is collaborating closely with many environmental stakeholders and regulatory agencies, including but not limited to Larimer County, Colorado Parks and Wildlife, the U.S. Fish and Wildlife Service, the U.S. Army Corps of Engineers, the U.S. Bureau of Reclamation, the State Historic Preservation Office and tribal nations, to protect, conserve and enhance the Chimney Hollow valley environs for current and future generations.
The Chimney Hollow Reservoir Project’s many environmental commitments will change and evolve during the project timeline to meet goals and objectives, and are a critical component for a successful project. “Water is the number one resource for human life,” Henry said. “But our stewardship responsibility in this project is huge. We can’t stop using water, but we have to be better stewards as we use it.”