Summit County Citizens Voice

Future water levels in Dillon Reservoir could be affected by a large-scale Denver Water plan to increase diversions from the Blue River Basin. PHOTO BY BOB BERWYN.

Although a draft study says impacts to  Summit County  are not significant, the Moffat Tunnel project could shorten the boating season and impact fish on Lower Blue and affect the Frisco and Dillon marinas

By Bob Berwyn

SUMMIT COUNTY — Local residents will have a little more time to comment on a Denver Water plan to export more high country water to the Front Range via the Roberts Tunnel. The public comment period for the project has been extended through March 17.

At issue is the Moffat Collection System Project, which focuses on diversions from the Fraser River in Grand County, but also would affect the Blue River in Summit County.

At a meeting last month, local officials expressed concerns about how changes in the operation of Dillon Reservoir could affect marinas in Frisco and Dillon, and about decreased flows in the Blue River below Dillon Dam.

For Denver Water, the Moffat project has three main goals:
- Reducing the risk of a near-term water supply shortfall;
- reducing the risk of running out of water in the north end of the system during a single dry year;
- addressing a serious imbalance in Denver Water’s collection system, in which about 80 percent of the supply exists on the south side of the system.

Read Denver Water’s call for public comment on the project here.

A draft environmental study shows that, at completion of the project, Denver Water could divert an additional 4,800 acre feet of Blue River water through the Roberts tunnel, equal to about 2 percent of the Blue River’s annual flow. A scoping summary report is online here.

The increased diversions from Dillon Reservoir would result in less water for the Gold Medal trout fishery in the tailwaters below Dillon Dam, a shorter boating season on the Lower Blue and a lower volume of flushing flows that are critical to maintaining stream health, said Steve Swanson, director of the Blue River Watershed Group.

“It will shorten the rafting season. There will be less water for longer periods of time,” Swanson said, explaining that the watershed group will host a March 9 public forum in Frisco generate more awareness about the project’s impacts in Summit County.”There’s so much more they could be doing before coming for more water over here,” he said, explaining that Denver Water should be doing more recycling and conservation.

Along with presentations from local water experts and government officials, the watershed group will hold a letter-writing workshop to help residents compose effective messages on the project. John Hagan, a volunteer coordinator with the watershed group, said he doesn’t think there’s enough public awareness about how the Moffat project will affect Summit County.

“This is one of the biggest things in Summit County since the dam was built,” Hagan said.

Denver Water planning director Dave Little said that about $5 to $6 million have been spent on the environmental analysis. Through the draft phase, the study has not identified significant impacts in Summit County. The main U.S. Army Corps of Engineers page with links to documents and public comment information is at this link.

Impacts are subjective

To some degree, the question of how significant the impacts are is subjective. On the scale of the overall Blue River watershed, the reduced flows in the Blue at its confluence with the Colorado River may only be a blip. But to a small local rafting company running tours on the Lower Blue, shortening the season by a few days each summer could add up to big financial hit.

Similarly, lower water levels in Dillon Reservoir could shorten the season for the Frisco Marina, located in shallow waters. That could make it tougher for the marina to operate viably.

While the draft environmental studies didn’t identify significant impacts in Summit County, the final version of the document could address additional issues that are raised through the public comment proccess, Little said.

According to Swanson, Denver Water is not honoring its obligations under the Blue River Decree, a 1955 legal agreement that specifies how water from Dillon Reservoir is to be used. Specifically, Swanson said Denver Water promised to only use water from Dillon Reservoir in its service area, the city of Denver. “Nobody knows if the water from Dillon Reservoir is staying in that service area,” Swanson said.

According to Swanson, the decree also requires Denver Water to use its Dillon Reservoir supply “to extinction,” meaning that the water needs to be recycled and re-used until its gone. Swanson said Denver Water only has one re-use facility that doesn’t come close to meeting the conditions of the decree.

“What Steve is saying is false,” Little responded. At best, the provisions of the Blue River decree are “nebulous” and open to legal interpretation, according to Little. With regard to the service area, the decree talks about Denver Water serving the greater metro area as it becomes socially and economically integrated, Little said, paraphrasing the language of the document.

References to a specific geographic service area relate to a boundary the Denver Water Board imposed on itself in the wake of the Two Forks Dam denial, post-dating the Blue River decree, Little said.

As to re-use of water, he said the decree calls for implementation of reasonable measures to ensure that Dillon Reservoir water is being used efficiently, he explained.

“That’s the rhetoric that’s being spun,” Little said, referring to Swanson’s allegations about the Blue River Decree.

Currently, Denver Water and Western Slope stakeholders are in a mediation process aimed at resolving some of the differences over interpretations of the decree’s language. The parties have agreed not to sue each other during the mediation. Little said the moratorium on legal battles was implemented to avoid showdowns over exactly those issues raised by Swanson.

Mitigation

Denver Water officials have said they will try to offset the impacts of increased diversions from the Western Slope with $2 million to pay for stream modifications in Grand County and another $2 million for water quality improvements, also in Grand County.

“We have been working with interest groups and local agencies … to provide significant environmental enhancements for the communities affected by the project,” said Little. There are no line-item mitigation measures specified to address potential Summit County impacts, but that doesn’t mean those impacts will be ignored, he said.

“Our customers have done an excellent job of conserving water, and we have been completing our recycled water system,” said Little. “These strategies are helping extend our supplies into the future. It is imperative, however, that we develop additional supply to correct the imbalance in our system and secure water for our future. We believe the best solution is to produce new water supply by expanding an existing reservoir instead of building a new reservoir.”

The Moffat Collection System Project would raise the height of Gross Dam in Boulder County by about 125 feet. Gross Reservoir is fed by tributaries of the Colorado River and South Boulder Creek, and feeds the north side of Denver Water’s system.

If approved, the Moffat Project would produce 18,000 acre-feet of new supply — enough water for about 45,000 households annually. The U.S. Army Corps of Engineers is also looking at several other alternatives, including combinations of more reservoir storage and aquifer recharge. An outline of the other alternatives is online here.

Filed under: Environment, rivers, Summit County Colorado Tagged: | Blue River, Blue River gold medal fishery, Denver Water, Dillon Marina, Dillon Reservoir, Environment, Frisco marina, Moffat Tunnel Collection Project, Summit County Colorado, Summit County News, trans-mountain diversions, water diversions