Water district, environment group reach Coffintop accord

LONGMONT — The St. Vrain and Left Hand Water Conservancy District announced Monday that it has reached an agreement with environmental group Save the World’s Rivers on a new path forward for the district’s Coffintop Reservoir water rights — one that does not include construction of a large on-river dam.

The district and Save the World’s Rivers reached an agreement through the water court process under which the district agreed to forgo using the Coffintop Reservoir water rights for any new on-river reservoir, including Coffintop Reservoir, and for the expansion of any existing on-river reservoir. Instead, the district will return to water court with plans to use the water rights at alternative locations and in ways that align with community needs, and environmental and water management goals.

The district was created in 1971 in part to build Coffintop Reservoir on South St. Vrain Creek west of Longmont and upstream of Lyons, through a planned partnership with the U.S. Bureau of Reclamation. While the reservoir itself was never built, two water storage rights associated with the project remain legally valid today.

As a governmental entity, the district holds the Coffintop water rights. In 2024, as required under Colorado water law, it filed a routine six-year diligence application in water court to maintain those rights. That filing prompted Save the World’s Rivers to submit a statement of opposition, opening discussions between the two organizations about the future use of Coffintop water rights.

“The water court process is complex, and at the onset we were uncertain what Save the World’s Rivers hoped to achieve through it,” Sean Cronin, the district’s executive director, said in a prepared statement.

“We are always watching proponents of dams,” added Gary Wockner, a Fort Collins-based activist who is executive director of Save the World’s Rivers and has been vocal for years about protecting the Cache la Poudre and Colorado rivers. “At the appropriate time, we seek to identify ways proponents can achieve their mission while not creating a new dam.

“We were generally aware of the good work being done by the district, but concerned about their plan to build Coffintop Reservoir and dam,” he said.

Cronin’s and Wockner’s entities held talks and found common ground.

“I met with Gary several times,” Cronin said, “and I gained respect for his organization’s objectives, and appreciated his willingness to come to the table and talk through complicated issues.”

Save the World’s Rivers learned that the district had been working for more than 10 years with the City of Longmont, Town of Lyons, Boulder County Parks and Open Space, local environmental organizations and food producers to develop a strategy to best utilize the Coffintop Reservoir water rights – without building the actual reservoir.

“It became clear through discussions that the district shared values around avoiding a new on-river dam while still meeting its mission,” Wockner said. “That made an agreement possible.”

District leaders emphasized that the water rights are held for public benefit and that the original Coffintop Reservoir concept no longer reflects the highest and best use of the resource.

“This is something we and our communities have contemplated for decades,” Christopher Smith, president of the district’s board of directors, said in a prepared statement. “The Coffintop project, as envisioned more than 50 years ago, no longer fits today’s needs or values.”

Lyons Mayor Hollie Rogan welcomed the agreement.

“St. Vrain Creek is the lifeblood of our town, and a large dam upstream was never embraced by our community,” she said. “We’re pleased the district will not pursue Coffintop Reservoir and look forward to continued collaboration.”

Chris Huffer, Longmont’s director of water and waste services, noted the long history between the city and the district.

“The challenges around water have only grown more complex over the last 50 years,” he said. “The district has a solid water plan, and the city is an eager partner in realizing the greatest potential of these water rights.”

The pact announced Monday is the second major agreement with a water provider for Wockner. In March 2025, nearly two decades of wrangling over the massive proposed Northern Irrigation Supply Project ended with a settlement between the Berthoud-based Northern Colorado Water Conservancy District, the organization that wants to build it, and Wockner’s nonprofit Save the Poudre. The pact cleared the way for construction of the $2.25 billion project and established a fund to protect the Cache la Poudre River.

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