Littleton City Council on Aug. 7 officially expressed concern about the plan to reconfigure Chatfield Reservoir, signing on to a letter crafted by the South Platte Working Group that calls for more explicit information.
In an effort to help meet the growing demand for water in the metro area, the Army Corps of Engineers’ study recommends reallocating 20,600 acre-feet of water from flood control to usable storage. This would raise the water in the recreation area by 12 feet, covering more of the park with water and requiring reconfiguration of the marina and other amenities.
SPWG comprises officials from areas downstream from the dam – Littleton, Arapahoe County, Englewood, Sheridan, South Suburban Parks and Recreation District and Columbine Valley. While they’re supportive of the goal to create more water storage, they’re concerned about data indicating that the reconfiguration could further diminish the South Platte River’s already mucky water flow eight months out of the year.
“Our working group is focusing on maximizing the potential of the South Platte River to provide recreational opportunities for the citizens of Arapahoe County and other Metro Denver residents,” they write. “Additionally, the cities along the river are already struggling to meet water quality requirements under tight budgetary restraints. A further reduction in flows in the South Platte would seriously and negatively impact our ability to improve and share this important amenity as well as the cities’ ability to provide safe drinking water to their residents.”
Nobody is sure yet how the proposal would affect the Littleton/Englewood Wastewater Treatment Plant, which is already facing more stringent federal requirements in the next few years.
Of particular concern to SPWG is how the Corps collected flow data it highlighted. Not included in the body of the report are measurements taken between the dam and Denver, where several creeks join the river, although those numbers are tucked away in an appendix.
“(The data) seems to be underemphasized as an integral part of the study’s analysis,” reads the letter.
They also note the phrase “adaptive management” is used more than 200 times throughout the study but never fully explained.
“It is not clear how an adaptive management process might be used to address potential impacts related to downstream flows,” reads the SPWG letter. “Our expectation is that an adaptive management process would include the affected communities downstream in Arapahoe County with necessary financial support to conduct an effective, thorough and fair process.”
Chatfield Dam is an integral player in the south metro area with lots of eyes on it, especially in drought years such as this. Even as the SPWG has been convening, the High Line Canal Working Group is trying to figure out how to save the old cottonwoods on the assumption it can’t rely on the river to feed the canal anymore. Additionally, the Littleton Community Retreat recently decided to focus on revitalization of the river corridor as an economic engine.
The local Audubon Society says it plans to sue if the proposal goes forward, citing concerns about habitat for birds and amphibians, in particular. Audubon members worry the plan would turn Chatfield State Park into a prairie and the river into a mud puddle.
Districts upstream, like Centennial Water and Sanitation, which serves Highlands Ranch, are footing part of the bill for the $5 million study. They have junior rights to Chatfield water, mostly used by Denver Water. They’re worried the underground aquifers they mostly depend on will dry up, and Parker Water and Sanitation is trying to figure out how to fill its new Rueter-Hess Reservoir. They’d all like a piece of the extra water Chatfield will be able to store once reconfigured.
Proponents say the Chatfield reconfiguration would be a boon to water providers, farmers and environmental organizations as it helps to met the need for water in a growing state. Northeastern Colorado farmers, for instance, could get more water for irrigation, proponents say, while communities could have more availability of water for drinking and other uses.
They also say that if the Army Corps of Engineers proceeds with the work, environmental impacts will be fully mitigated.