The city of Aspen has put forward a proposal that would move its conditional water-storage rights, and with it two potential dams and reservoirs, out of the Castle Creek and Maroon Creek valleys and spread a proposed 8,500 acre-feet of water storage among as much as six locations between Aspen and Woody Creek.

That deal was well-received Thursday by opposing parties in two water-court cases tied to the potential Castle and Maroon reservoirs during a brief water court status conference. The city circulated a settlement proposal Dec. 8 to the 10 parties opposing the city’s efforts to maintain a conditional right to store 4,567 acre-feet of water in a potential Maroon Creek Reservoir and 9,062 acre-feet in a potential Castle Creek Reservoir.

In its proposal, according to sources close to the negotiations, the city said it will seek to transfer its conditional storage rights from the two reservoirs to other potential reservoirs on a range of other sites that could hold as much as a combined 8,500 acre-feet of water from Maroon and Castle creeks.

The reservoirs, either surface or underground “in-situ,” would be built on a range of potential locations including the city’s golf course, the Moore, Burlingame, and Cozy Point open space parcels, the gravel pit in Woody Creek operated by Elam Construction, and a parcel of vacant land next to the gravel pit the city now has under contract.

Under the deal, the city would make a firm commitment to move its potential reservoirs out of the Maroon Creek and Castle Creek valleys, and the opposing parties would refrain from fighting the city’s future efforts in water court to transfer its conditional storage rights, and its 1971 decree dates, to the new locations.

“Based on what I’ve heard today it sounds like … there is some consensus that the cases are moving toward settlement,” Division 5 water court referee Susan Ryan said Thursday after each of the attorneys in the two cases stated their view of the ongoing settlement negotiations.

Ryan set another status conference in the two cases for Feb. 15.

The city filed two periodic applications with the court Oct. 31, 2016, to show it’s been diligent in developing its conditional storage rights for the Maroon and Castle creek reservoirs, which it first filed in 1965. The recent applications drew opposition from the U.S. Forest Service, Pitkin County, American Rivers, Colorado Trout Unlimited, Western Resource Advocates, Wilderness Workshop, and four private landowners, two in each valley.

James DuBois, an attorney with the U.S. Justice Department in Denver, told the referee during Thursday’s status conference that “as far as the United States’ objections, I think it’s likely we’ll be able to reach settlement.”

Craig Corona, a water attorney representing the Larsen family, which owns property in Maroon Creek, also was bullish on the city’s proposal to move the water rights out of the valleys.

“Larsen Family LP feels like we’re making substantial progress in negotiating toward a settlement,” Corona told the water court referee. “And we’re happy to stay on the referee’s docket at least for another 45 days to try to finalize the settlement agreement.”

Any party in a water court case has the option at any time to re-refer a case away from a settlement track under the purview of a water court referee and put the case on a trial track in front of a water court judge.

Paul Noto, a water attorney representing American Rivers, Colorado Trout Unlimited, and another Maroon Creek landowner, told the court, “My broad view of the status is that we are making some headway toward settlement and I’d prefer, for one, to avoid trial-track deadlines and focus on settlement issues.”

Rob Harris, a staff attorney at Western Resource Advocates, who also is representing Wilderness Workshop, said, “I agree that we’ve made significant progress toward settlement and I think we’d benefit from at least another couple months or so to pursue settlement.”

Attorneys for Pitkin County and the two property owners in Castle Creek said they did not object to the case staying in front of the referee.

Aspen’s water attorney, Cynthia Covell, told the court that the city has only just recently received a number of written comments to its proposal from the opposing parties, and that the city would like about a month to review them and further discuss its proposal with the parties.

A view of a parcel of land next to the Woody Creek gravel pit, in background, that the city of Aspen has put under contract to buy for water storage purposes. The city has proposed moving its conditional water storage rights out of the Castle Creek and Maroon Creek valleys and storing the water in reservoirs in Woody Creek and four other locations. Credit: Brent Gardner-Smith/Aspen Journalism

Storage options

Aspen officials have been reviewing alternative water storage sites for about a year with the help of Deere and Ault, an engineering firm in Longmont.

A study done in September by Deere and Ault identified a range of in-situ and surface reservoirs that could be built, in differing combinations, on the Woody Creek gravel pit site and the neighboring parcel of land the city intends to buy.

The options include a 320 acre-foot in-situ, or underground, reservoir and five options for surface reservoirs in various configurations that would hold between 700 acre-feet and 8,000 acre-feet of water. The Woody Creek reservoirs range in cost from $48 million to $81 million and would require about 6.5 miles of pipeline to reach the city’s water treatment plant.

Deere and Ault has also found, in a screening study of various sites, that the city could store water in a number of potential in-situ reservoirs on other sites upvalley from Woody Creek.

In-situ reservoirs require deep trenches dug 50 to 100 feet down to bedrock, depending on the site. The trenches form the walls of the storage vessel, or bucket, while the bedrock, and sometimes a geosynthetic liner, forms the bottom of the bucket.

The rocks and dirt on the site are not excavated, but left in place between water-tight slurry walls poured into the surrounding trenches. Water is then poured into the bucket and pumped out for later use.

Deere and Ault found that an in-situ reservoir could be built on the city-owned Moore open space, across Maroon Creek Road from the Aspen Chapel, to hold 550 acre-feet of water, at a cost of $26.9 million. The water could then be pumped nearly a mile via a pipeline to the city’s water treatment plant, which is on a hill behind Aspen Valley Hospital.

The city’s golf course could hold two in-situ reservoirs, one holding 650 acre-feet and another holding 760 acre-feet, for a total of 1400 acre-feet, at a combined cost of $71.3 million.

The Burlingame, or Zoline, open space, which is 1.9 miles from the water treatment plant and owned by the city, could accommodate a 650-acre-foot in-situ reservoir, at an estimated project cost of $34 million.

The Cozy Point open space, also owned by the city, could hold two 100-acre-foot reservoirs for a combined 200 acre-feet of storage. The site is 5.6 miles from the water treatment plant and the estimated project cost for the reservoirs and pipeline system is $15.5 million.

Editor’s note: Aspen Journalism is collaborating with The Aspen Times, the Glenwood Springs Post Independent, the Vail Daily, and the Summit Daily on coverage of rivers and water. The Times published this story on Thursday, Jan. 5, 2017.

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...