Thornton pipeline for Poudre River water faces Larimer County decision

It’s been more than five years since the Larimer County commissioners said no to Thornton burying miles of pipe in the county to transport water from the Cache la Poudre River. Now the northern Denver suburb is back in the same hearing room.

And it has the same basic request: Let us move the water we own to our fast-growing and thirsty community.

Larimer County’s board of commissioners will decide the fate of the 70-mile, half-billion-dollar infrastructure project as soon as Monday. As now proposed, the pipeline would follow an alignment that’s different from the one rejected in 2019.

Instead of cutting through properties for 27 miles — a prospect that rankled landowners half a decade ago — the pipe would traverse just 10.4 miles inside Larimer County.

Ultimately, the commissioners will have to balance Thornton’s demands for water to support much-needed housing in the city of 145,000 against calls by county residents and environmentalists for an alternative that avoids putting the Poudre’s water in a pipe in the first place. They contend other outcomes would maintain the health of the river.

Colorado’s sixth most populous city wants to move 14,000 acre-feet of Poudre water to the city annually, via a 42-inch-diameter pipe.

It’s possible a final vote by the commissioners could be delayed until Wednesday, depending on how much more public comment there is Monday.

“Our rivers face a mild health crisis and the Poudre is no exception,” Preston Brown, a river restoration expert who lives in Larimer County, told the commissioners at an initial hearing on the permit late last month.

He was among a group of residents who touted the “Poudre River Option,” whereby Thornton leaves the water in the river through Fort Collins and then takes it out near Windsor. That would restore healthy flows to a waterway that has seen demand on its resource increase, they argue.

The Poudre River through Fort Collins received a C grade for its health in a study the city issued several years ago.

“I want to raise up the rights of nature,” Gailmarie Kimmel, who works for Fort Collins-based environmental advocacy group IDEA WILD, said at the April 22 hearing. “This is an opportunity to act as guardians and kin.”

City: Project “does not reduce the river flows”

But Carolynne White, an attorney representing Thornton, noted during the hearing that the city has owned its shares in the Poudre River for decades.

It’s been diverting that portion of water into reservoirs northwest of Fort Collins, for use on farms in the area. Those water shares are the ones Thornton would send directly to the city through the pipe, rerouting water that does not flow through Fort Collins currently.

“This project does not reduce the river flows in the Poudre River,” White said.

For emphasis, she said it twice.

Several homebuilders addressed the commission at the hearing. Chad Murphy, managing director at global real estate firm Hines, said the company owns 800 acres in Thornton where it wants to build a 4,000-home neighborhood known as Parterre.

No water means no homes, he said — bad news for a state estimated to be 100,000 homes and apartments short of what’s needed for its population.

“Denying the Thornton water project would impact the Colorado economy,” Murphy said. “If Colorado is closed for business, fewer employers will come to our state and it will send our economy into a downward spiral.”

The commissioners also heard from Adam Zard, a developer of multifamily housing at Maiker Housing Partners, Adams County’s housing authority. He said an 80-unit affordable housing project near an N-Line rail station in Thornton is on hold while the water dispute drags on.

“Unfortunately, our progress has stopped while we wait for Thornton and Larimer County,” he said.

Earlier denial was upheld by courts

Thornton long has argued that it doesn’t want its drinking water running through Fort Collins — absorbing urban runoff and passing three wastewater treatment plants — on the way to residents’ taps. The pipe, which would head east from the Poudre and past Interstate 25 before veering south to Thornton, would ensure water quality stays pristine.

The city took Larimer County to court over its February 2019 denial, losing in district court and again during the appeals phase.

But the Colorado Court of Appeals in its 2022 ruling concluded that Larimer County can’t force Thornton to keep the water it owns in the Poudre River.

“We are hopeful, given the clear guidance from the Court of Appeals decision, which is binding to the parties of that court case, that the county commissioners agree they are focused on deciding if Thornton’s alignment of a pipeline meets their (land-use) criteria,” city spokesman Todd Barnes told The Denver Post.