Gross Reservoir Expansion Project update

Gross Dam enlargement concept graphic via Denver Water

From The Summit Daily News (Kevin Fixler):

The U.S. Army of Corps of Engineers officially threw its support behind the proposed expansion of Denver Water-owned Gross Reservoir, aka the Moffat Collection System Project, to triple capacity of the storage facility this past Friday. The review process has been nearly a decade and a half in the making as the Front Range tries to keep pace with population and expected water consumption growth by pulling more of the resource off the Colorado River in headwater communities along the Western Slope.

Just to reach the milestone and obtain buy-in from the region, Denver Water spent six years in negotiations with Summit, Grand and Eagle counties and 14 other stakeholders, as well as several other subsidiary entities. The result was the Colorado River Cooperative Agreement, which gave way to the impacted counties accepting the terms to allow the metro area’s municipal water agency to remove water to which it already owned the rights.

“While some may say 14 years is too long, I believe complicated issues deserve thorough study,” Jim Lochhead, Denver Water CEO and manager, said in a news release. “In accordance with other agreements we’ve implemented along the way, Denver Water will provide millions of dollars to improve watershed health in the critical Colorado and South Platte River Basins. The project enjoys broad, bipartisan support from lawmakers, major environmental groups, chambers of commerce and water interests on both sides of the Continental Divide.”

An environmental group that does not share in the reverie, however, is Save The Colorado, a nonprofit water advocacy organization against the project to divert 15,000 more acre-feet of water from the Colorado River…

Save The Colorado’s attorneys are presently reviewing the Army Corps’ record of decision in anticipation of a suit to be filed in federal district court in Denver as part of a larger coalition that may include Boulder homeowners who live around the reservoir’s perimeter. A requested injunction may be part of the legal strategy should Denver Water begin construction on the 131-foot heightening of the existing 340-foot dam wall if a few other smaller-scale permits are secured, but the aim is preventing it from ever coming to fruition.

“Our goal is stop the project, not slow it down,” said [Gary] Wockner…

Summit’s Board of County Commissioners believes the complex deal is a fair one, considering what the area’s water future may have looked like without it in place. Aside from other considerations to keep Denver Water’s appetite in check in the years to come, $11 million in cash — $2 million of which has already been paid — will ultimately be split evenly among the county government and its four major towns of Breckenridge, Dillon, Frisco and Silverthorne for future water and other environmental enhancement projects.

Various county entities, including Summit’s four ski resorts, also stand to receive access to a combined 1,700 acre-feet (approaching 570 millions of gallons) of water annually not previously available out of Denver Water-owned Dillon Reservoir. Grand County is to receive $6 million in payments upon the bypassing of possible legal barriers and final execution of all permits, on top of additional water and adaptive management assistance, while Eagle received some legal assurances of its own.

“This agreement provides for our economy, our environment, our way of life and are things we could have never gotten had we fought Denver Water in court,” said County Commissioner Thomas Davidson. “Denver Water already had these water rights, and that was something we from the Western Slope had to keep reminding ourselves of. Each side had to give up or give in on things they felt very passionately about not wanting to give up.”

With some exceptions, the compromise also better defines Denver Water’s service area to help prevent the expansion of those boundaries and the thirst for even more regional waters. The agency has committed to maintaining conservation activities and increasing reuse of water from the Blue River to reduce the need for more Western Slope water as part of these efforts. A guarantee to hold Dillon Reservoir at an accepted level for ideal aesthetic and recreational purposes from June 18 to Labor Day is a guarantee written into the agreement as well.

With the Army Corps’ endorsement as follow up to a prior certification granted by the Colorado Water Quality Control Division, Denver Water next needs a few remaining approvals from the Federal Energy Regulatory Commission, U.S. Forest Service and most likely a permit from Boulder’s Board of County Commissioners.

Denver Water is seeking approvals from the U.S. Army Corps of Engineers, the U.S. Fish and Wildlife Service, and the state of Colorado to expand Gross Reservoir, which is southwest of Boulder. The 77,000 acre-foot expansion would help forestall shortages in Denver Water’s water system and offer flood and drought protection, according to Denver Water.

From The Denver Post (Danika Worthington):

Denver Water CEO Jim Lochhead said the project, which was approved late Friday, was important to add balance and resiliency to the agency’s system. The dam expansion still needs approval from the Federal Energy Regulatory Commission to increase its hydropower capacity.

“It’s been a long haul,” Denver Water Board President Paula Herzmark said of Friday’s decision. “We are just ecstatic, just elated that this permit is now in place and we can begin. To have the insurance that we’re going to have this additional source of supply as our community grows.”

[…]

Colorado Trout Unlimited was happy with the news. The group has been working with Denver Water to make the project environmentally friendly, Trout Unlimited counsel Mely Whiting said.

The project includes an environmental pool to divert water to streams that need it. It also led to the Learning By Doing Cooperative Effort that brings together groups to monitor stream conditions and quickly take action when needed. Denver Water is also giving about $25 million to Grand County and other counties for environmental advancements…

Lochhead countered that the extra water will be needed as current conservation efforts won’t be enough to cover the growing population and effects of climate change. He added that Denver Water has been working with environmental groups and local and federal governments since the start to not just mitigate damage, but rather improve rivers.

Lochhead acknowledged that the five years of construction will be hefty, especially the three years of intensive concrete placing. He said Denver Water worked with the local residents to mitigate impacts and said an onsite quarry will be built to reduce truck trips.

“With a warming climate and with growth and other issues in our system, we need to make sure that our system is resilient in the long term,” he said.

From The Jackson Hole News & Guide (Allen Best):

Denver Water finally has a key permit that it needed to begin raising Gross Dam, located in the foothills northwest of Denver. The purpose is to triple the amount of water that can be stored there, including greater volumes of water diverted from the Winter Park area.

But the city still needs several more federal permits and may get caught in a legal fight. Unlike some water battles of the past, however, this one will come from elsewhere along the Front Range…

Denver Water has been working on this plan since the great drought of 2002 caused city water officials to realize the vulnerabilities of their system. The agency provides water not only to Denver, but many suburbs — altogether about a quarter of all Colorado residents.

“While some may say 14 years is too long, I believe complicated issues deserve thorough study,” said Jim Lochhead, Denver Water chief executive.

Denver has diverted water from the Fraser River and its tributaries since 1936 through the pioneer bore of a railroad tunnel under the Continental Divide. The water is impounded at Gross Dam. The dam already stands 340 feet tall, and Denver wants to raise the dam another 131 feet, to accommodate increased diversions.

Grand County, whose water will be diverted, has not opposed the project…

These diversions were mostly engineered in the 1930s. “Denver had a vision; we had none,” summarized Lurline Curran, who is the now-retired county manager of Grand County, at a water conference about a decade ago.

This time, Grand County sat down with Denver and brokered a deal. Denver gets more water, but it also agrees to work with Trout Unlimited and other local groups to try to take the water in ways that are least impactful to fish and other components of the ecosystem.

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