From Western Resource Advocates (Robert Harris):
Better management and use of existing dams is a key tool to minimize new expensive, energy-consuming, and environmentally damaging large scale new dams or diversions from the West’s rivers.
We are a conservation group with a priority goal of saving rivers in the West. So you would think we would be opposing anything to do with dams. But the reality is that we believe that better management and use of existing dams is a key tool to minimize new expensive, energy-consuming, and environmentally damaging large scale new dams or diversions from the West’s rivers. Which brings us to today’s story about supporting more creative management of Chatfield Reservoir and saving Plum Creek.
The U.S. Army Corps of Engineers recently approved storing more water in Chatfield Reservoir on the South Platte River southwest of Denver to help meet Colorado’s existing and growing water needs. Western Resource Advocates, Conservation Colorado, and the Rocky Mountain Chapter of the Sierra Club support this decision because it follows the Smart Principles of water supply management by making more efficient use of existing reservoirs and local water supplies. In our view, select new-supply projects—including holding more water in the existing Chatfield Reservoir—high rates of water conservation, accelerated water recycling and reuse, and voluntary sharing of water with agriculture for other uses all can combine to meet and exceed 2050 water demands for the South Platte Basin. “Chatfield Reallocation” exemplifies the opportunities available to state water planners to meet reasonable anticipated water needs without building more costly, politically charged, large-scale concrete and steel water project proposals that cause major harm to rivers.
However, putting more water in Chatfield Reservoir will still harm wildlife habitat provided by nearby wetlands and cottonwood stands. These habitat areas are accustomed to a lower, and less variable, water table in the reservoir. As part of the agreement to re-allocate water storage space in Chatfield reservoir, the environmental impacts must be offset, or “mitigated,” through replacement and permanent protection of other wetlands and other important wildlife habitat. To this end, the project’s beneficiaries have deposited approximately $130 million into a special bank account dedicated to environmental and recreational mitigation. Western Resource Advocates is joined by representatives of relevant state and federal agencies and other stakeholders as a member on the Technical Advisory Committee for the Chatfield Reservoir Reallocation Project, which guides implementation of the environmental protection and restoration mitigation projects.
At its first meeting in late April, the Committee urged the mitigation company to use some of the mitigation funds to address rapidly deteriorating wildlife habitat along Plum Creek, which is above the reservoir in the park. Urban development in the Plum Creek watershed has significantly increased rain runoff flows that are scouring a deep channel into the creek bottom, and in turn, lowering the water table and draining high-quality wetlands next to the creek. This erosion, called a “head cut,” is unrelated to the Chatfield water storage project.
This year, the head cut in Plum Creek is advancing dozens of feet upstream with each rain storm. Western Resource Advocates and the Committee unanimously urged the mitigation company to stabilize the creek and stop the head cut. This will help restore Plum Creek’s health and provide good creek-side habitat for birds and other wildlife.
Mitigation projects like this one on Plum Creek demonstrate the potential of creative water supply solutions, including Chatfield Reallocation, to meet communities’ water needs and to fix significant local and regional environmental challenges. It also illustrates how dynamic mitigation projects can be since few anticipated that this habitat would, on its own, deteriorate so badly in such a short period of time. Without mobilizing the mitigation funding made possible by this project, Plum Creek’s wetlands might be lost for generations. Stay tuned to the Chatfield Reallocation Project as the stakeholders develop and implement this and other exciting protections for wetlands and rivers.
Rob Harris is a Western Resource Advocates attorney representing WRA, Conservation Colorado, and the Rocky Mountain Chapter of the Sierra Club on the Technical Advisory Committee for the Chatfield Reservoir Reallocation Project.