ASPEN – The Aspen City Council is poised to take another step this evening toward someday constructing a 155-foot-tall dam in a pristine alpine meadow with a direct view of the Maroon Bells, as unlikely as that may sound.

The council is expected to approve a resolution tonight directing staff to file a diligence application in Division 5 water court in Glenwood Springs by Oct. 31 in order to maintain conditional water rights tied to potential dams on both upper Maroon and Castle creeks.

“The purpose of conditional decrees like these conditional storage rights is to allow the city to proceed to perfect the water rights with the decreed priority dates,” states the draft resolution, which is on the meeting’s consent agenda.

In order to “perfect the water rights” as currently proposed, the city would need to build a dam on upper Maroon Creek that would back up 4,567 acre-feet of water over 85 acres.

The stored water would flood the “wedding meadow,” with its dramatic views of the Bells, and also inundate portions of the Snowmass-Maroon Bells Wilderness.

To “perfect” its conditional rights on Castle Creek, the city would need to build a 170-foot-tall dam two miles below Ashcroft that would back up 9,062 acre-feet of water over 120 acres of mainly private land.

(Please see maps of the potential Maroon Creek and Castle Creek reservoirs.)

While many scoff of the chance at either dam ever being built, the city’s resolution indicates it still intends to build them.

“The city’s planning and phased development of its integrated water supply system continues to demonstrate its diligence in development of these conditional storage rights,” the resolution states.

It also says, “the city is obligated and intends to provide a legal and reliable water supply and to that end can and will develop all necessary water rights, including but not limited to, Maroon Creek Reservoir and Castle Creek Reservoir.”

However, a series of recent staff memos to the council have also stressed that maintaining the conditional water rights “is not a proposal to actually build the reservoirs at this time.”

A beaver dam on Maroon Creek just upstream of the potential 155-foot-tall dam that would form Maroon Creek Reservoir. Credit: Brent Gardner-Smith/Aspen Journalism

Water court ahead

On Sept. 27, at the second of two work sessions on the upcoming deadline to file in water court, City Council members unanimously indicated they support holding on to the conditional rights as protection against a much drier future.

As such, the draft resolution poised for approval tonight directs staff to file a diligence application by Oct. 31.

The lengthy resolution also appears to have been written with water court in mind, as it also addresses a number of issues often relevant in conditional water cases.

Both the U.S. Forest Service and American Rivers have recently declared they intend to oppose in water court the continuation of Aspen’s conditional rights.

Perhaps with that in mind, the resolution states the city should “initiate a collaborative process” to evaluate “necessary actions” to meet an “updated anticipated water supply and demand gap.”

Wilderness Workshop of Carbondale is actively working to convince the city to abandon the conditional water rights, citing the environmental degradation that comes from dams, among other reasons.

On Saturday, the conservation director for Wilderness Workshop, Will Roush, conducted a site visit to both dam sites for about 10 interested citizens.

While standing in the meadow in view of the Maroon Bells, where Roush had strung orange tape marking the alignment of the potential 155-foot-tall dam, Gretchen Straub of Aspen exclaimed, “It just baffles me that this would even be considered. Forget the fact that we don’t need it, and there isn’t data to support that we will ever need it,” she said. “Just the fact of it even being discussed and contemplated, to do it to both of these streams, in both of these pristine wildernesses, is beyond belief.”

Ruth Harrison of Aspen, standing next to Straub, added, “We should have the city council meeting here on site.”

A view from where a potential dam would stand on Maroon Creek if the city of Aspen perfected its conditional water rights tied to a potential Maroon Creek Reservoir. Credit: Brent Gardner-Smith/Aspen Journalism

On the books since ‘71

The city first filed for storage rights on the two creeks in 1965 and was granted conditional decrees in 1971. Since then, the city has periodically told the state, most recently in 2009, it still intends to build the dams

The city has not, however, undertaken any studies of the two dams since 1970, when a Bureau of Reclamation drill test found poor soil conditions at the Castle Creek dam site.

Nor has the city done a recent analysis of how much water it might need to store someday, or where it might optimally do so.

In addition to its conditional storage rights, the city owns pre-1900 senior water rights to divert up to 160 cubic feet per second (cfs) of water from Castle Creek and 65 cfs from Maroon Creek. It’s under these water rights that the city provides water today.

The city’s use of water from the two creeks currently ranges from 3 to 9 cfs to meet treated water demands and up to 30 cfs to meet peak summer irrigation needs, according to a recent water availability study commissioned by the city.

The study, notably, concluded that the city did not need new storage capacity to meet its long-term domestic water needs or to protect environmental flows in the creeks.

“The city can always provide sufficient potable and raw water supplies,” the study concluded after looking 50 years into the future.

A wetland in the upper Castle Creek valley that would be flooded by a potential Maroon Creek Reservoir, which would be formed by a 170-foot-tall dam. Credit: Brent Gardner-Smith/Aspen Journalism

Open to change?

The draft resolution includes language suggesting the city is open to changing the proposed size and locations of the dams.

The resolution finds that the city “should also continue to further investigate alternative locations and sizing requirements” of the two reservoirs.

And, “if appropriate,” the city should “seek water court approval for modification of one or both conditional decrees, with their existing appropriation dates.”

The city council meeting begins today at 5 p.m., in city hall.

Editor’s note: Aspen Journalism and the Aspen Daily News are collaborating on coverage of rivers and water. The Daily News published this story on Monday, Oct. 10, 2016.

Brent Gardner-Smith

Brent Gardner-Smith, the founder of Aspen Journalism, and who served as AJ’s executive director until August 2021 and as editor from 2011-2020, is the news director at Aspen Public Radio. He's also been...