Karin Summers, of Nederland, holds a sign Thursday during a Boulder County Commissioners meeting regarding the Gross Reservoir expansion at the Boulder County Courthouse on Pearl Street in Boulder. The commissioners voted unanimously that the planned expansion must be reviewed at the county level. (Jeremy Papasso / Staff Photographer)

After more than four hours of impassioned pleas from members of the public Thursday night, Boulder County commissioners voted unanimously that Denver Water's planned expansion of Gross Reservoir must go through the county's review process.

That vote, affirming an earlier finding by Boulder County Land Use Director Dale Case, now poses a significant challenge for the utility, which serves 1.4 million water users in the Denver metro area — none of them in Boulder County — and claims the project is needed to meet the needs of metro population that's just going to keep growing."

I think it's just critical that local people have their say on this project that affects them the most," said Boulder County Commissioner Matt Jones, just before the vote was taken.

The vote by commissioners — who were serenaded by one wind chime-wielding citizen warbling a customized version of the Doobie Brothers' "Black Water" — adds one more hurdle that stands between Denver Water and pulling off what would be the largest construction project in Boulder County history.

Other bumps in the road include a federal lawsuit filed at U.S. District Court in Denver in December by environmental activists seeking to block it. The project also still requires a hydroelectric licensing amendment from the Federal Energy Regulatory Commission — although the FERC staff on Feb. 8 recommended that its commissioners to grant that amendment.

Denver Water's plan had been to start construction this year on a project to raise the Gross Reservoir Dam in southwestern Boulder County by 131 feet to a height of 471 feet and to expand the reservoir's capacity by 77,000 acre-feet.

The cost of the endeavor, said to be the biggest construction project ever contemplated in Boulder County, is now estimated at $464 million (in 2025 dollars) and could take at least six years to complete.

Boulder County Land Use Director Dale Case issued a finding on Oct. 22 that Denver Water's plans, formally known as the Moffat Collection System Project,were subject to the county's so-called "1041" review process — that number references the state House bill passed in 1974 allowing local governments to regulate matters of statewide interest through a local permitting process.

Denver Water however, has argued to the contrary.

"We contend that state law exempts the expansion from the 1041 process because it was permitted under local land use codes at the time that the state enacted the law authorizing the 1041 review process," said Denver Water spokesman Travis Thompson.

Roughly four dozen people had signed up online to speak in the days leading up to Thursday night's hearing, and many more did so in person in the hour before the session started. A number of them were members of The Environmental Group, local environmental advocates who fear the project will be harmful both to natural resources and to mountain neighborhoods that would be impacted by the project.

Public sentiment at the meeting was overwhelmingly in opposition to exempting Denver Water's plans from a county-level review.

Beverly Kurtz, a board member of the group who lives on the north side of Gross Reservoir, was one of many who spoke to commissioners while sporting a T-shirt emblazoned with the word "RESIST," above a raised fist."

We are dealing with a finite resource," Kurtz said. "Just because you build a dam, it does not mean the water will come."

While many addressed feared impacts of the project in the reservoir's immediate proximity — the clear-cutting of hundreds of thousands of trees, harm to wildlife and the degradation of roads and the environment from many truck trips to and from the reservoir — Kurtz was among those who emphasized the fragility of the Upper Colorado River Basin, where she said flows could be reduced by 30 percent by 2050 by climate change.

In future years, what may be left at Gross Reservoir will be "nothing more than an ugly hole in the ground, as a testimony to greed and the lack of foresight," Kurtz warned.

She was followed by Boulder resident Gary Wockner, director of Save the Colorado, the lead plaintiff in the federal suit challenging the project. He spoke to an expansion's potential impacts not only on the Colorado River, but the Fraser and Blue rivers as well.

"Boulder County and the people of Boulder County should not be a sacrifice zone for Denver Water's river-draining schemes," Wockner said.

"It's simply ridiculous that they believe they don't have to go through your local permitting process to build the largest dam in the history of Colorado...and that would cause all these intense negative impacts."

Climate scientist David Bahr, a contributor to the International Panel on Climate Change who lives near Nederland, agreed, saying, "It's time to enact your 1041 review powers to stop a project that flies in the face of everything we understand about climate change."

Several representatives of Denver Water argued that the project was needed to right an imbalance that puts some 90 percent of its storage capacity at the south end of its system (Gross Reservoir is on the north). And they said they have strived to be — and will continue their efforts to be — good neighbors, detailing ways in which they have already modified the project in response to citizen feedback.

"We are committed to doing this project, and our customers need us to complete the Gross Reservoir expansion project," said Denver Water General Counsel Jessica Brody."

And we are equally committed to doing so in a way that respects the environment and the needs and concerns of our Boulder County neighbors and residents."

There was speculation by some in the crowd that a decision Thursday night adverse to Denver Water could trigger legal action; comments by Grand County Commissioner Merrit Linke, who addressed his Boulder County counterparts, had alluded to their vote opening up "a ton of litigation" involving Denver Water and others.

But Thompson, the Denver Water spokesman, did not speak to such a consequence, directly.

Denver Water will "continue to evaluate what the most appropriate processes are, under our permits and orders, to ensure we proceed in the most responsible way possible for our customers, the environment and the impacted communities," he said.

Denver Water's program manager Jeff Martin said, "For us, success isn't just getting the project done. Success for us is working with the community and keeping our commitments to our neighbors."

Very few of those "neighbors" at Thursday's meeting sounded like enthusiastic partners.

Charlie Brennan: 303-473-1327, brennanc@dailycamera.com or twitter.com/chasbrennan