Summer/Fall 2016 — The City of Aspen holds conditional water rights to build two dams on Castle and Maroon Creeks. While it seems incomprehensible that anyone would want to dam these two spectacular creeks, City Council members have indicated they will soon file in water court to prove they “can and will” build these reservoirs despite their own study which concluded that the City can always provide sufficient potable and raw water supplies. WW is dedicated to ensuring these rights are taken off the books so that Aspen never has the option to dam these two iconic creeks.

We covered the issue extensively in our publication, Wild Works.  Adapted from the Summer 2016 edition:


A diligence filing this fall would keep them alive; WW says, “No way!”

Since 1965 the City of Aspen has maintained conditional water rights to build two reservoirs on Castle and Maroon Creeks. To keep these rights, Aspen must submit a diligence filing this October. While this is a routine filing that occurs every six years, and not a proposal to actually build the reservoirs, it is an indication that the city intends to build them one day. The city has maintained these rights anticipating that they will use the reservoirs to provide municipal water to an expanding city.


This graphic representation was developed using maps and data from the City of Aspen and Colorado water rights documents. The exact locations of the areas that would be flooded may not be accurate due to slight changes made by the city of Aspen to the proposed reservoirs. Specifically, the Castle Creek Reservoir may be slightly smaller or downstream of the area depicted. The Proposed Castle Creek dam would be 170 feet tall and approximately 1,200 feet long. The Castle Creek reservoir would inundate 112 acres and hold 9,062 acre-feet of water.

As hard as it is to imagine, if Aspen goes ahead with its diligence filing this fall both these reservoirs could be built. Wilderness Workshop believes that the potential dams would be highly destructive to the character of these two valleys, inconsistent with the values of our community, and completely unacceptable. We have urged the city to abandon the conditional water rights during public meetings this summer.
Since 1965, the city has submitted diligence filings and successfully maintained these conditional water rights with little to no public process. “It is a water right which is something of great value to the City of Aspen and its water supply system,” said David Hornbacher, Director of Utilities. “We’re always looking long term and trying to determine how best to meet the needs of the community,” he said.

While building reservoirs at the headwaters of two of the region’s most iconic Valleys may seem far-fetched, the city has made clear that it sees the reservoirs as a real possibility for the future. In a statement released to Aspen Journalism in 2012, a committee of city officials wrote that “Aspen will build the Castle Creek and Maroon Creek reservoirs if necessary and in the best interest of the citizens of the community.”
Hopefully, it would never have to come to that, said Hornbacher. He touted the city’s successful conservation programs to point out that only as a last resort would more storage be considered. “We’ve improved the distribution system by eliminating leaks and other wasteful practices. We have a very active conservation program. We have tiered water rates. We encourage mindfulness when you use your water.”

Citizens had the opportunity to weigh in on the diligence filing during a series of public meetings held by the city. WW Conservation Director Will Roush noted that this effort by the city is new for this round of diligence. “It’s great to see the city taking an open and transparent approach to an issue I’m sure is of significant interest to the public.” The reservoirs run counter to our mission and organizational goals. “These reservoirs are simply not in keeping with the community’s values,” said Roush. “The proposed dams would inundate wilderness, flood treasured trails and place an ecological disaster and visual eyesore at the heart of two of our most popular valleys.”

The city makes a valid point that population growth and climate change create an uncertain future; one in which future water needs are unknown. However, a recently commissioned study of the city’s water supply shows that current diversion on Castle and Maroon Creeks, coupled with existing and future groundwater wells and conservation programs, can adequately supply municipal water for the next 50 years.


This graphic representation was developed using maps and data from the City of Aspen and Colorado water rights documents. The exact locations of the areas that would be flooded may not be accurate due to slight changes made by the city of Aspen to the proposed reservoirs. Specifically, the Maroon Creek Reservoir may or may not flood the Maroon Creek Road. The Proposed Maroon Creek dam would be 155 feet tall and approximately 1,300 feet long. The Maroon Creek Reservoir would inundate 80 acres and hold 4,567 acre-feet of water.

“The future is always uncertain,” said Roush, “but we make decisions all the time based on present values.” For example, our community set aside hundreds of thousands of acres as wilderness in the 1970s and 80s knowing we would never have the option to mine for silver or build roads through the mountains. And we are currently asking Congress to forever foreclose drilling for gas in the Thompson Divide despite an uncertain energy future. “City and county open space, for example, might be needed one day for more housing. But we are collectively willing to dedicate open space for permanent protection, regardless of anticipated future need. The same is true of these potential reservoirs,” he said.

While abandoning water rights may have been unheard of when these rights were first filed in 1965 and the country was on a dam-building spree, our thinking on water storage has evolved. In the past decade, dams across the country were removed to restore rivers. Just recently, conditional water rights to build two massive dams on the Crystal River were abandoned after years of work by local citizens and Pitkin County. We hope Aspen will realize that Castle and Maroon Creeks, as gateways to some of our most popular trails and wilderness areas, deserve to remain as they are: free-flowing and untouched by industrial development.