Save The Poudre is suing to stop NISP project that would provide water to 15 communities

Environmental group Save The Poudre has filed a lawsuit to try and stop the Northern Integrated Supply Project from going forward to construct two reservoirs and supply water to 15 communities.

The project is planned by the Northern Colorado Water Conservancy District, but the lawsuit was filed against Lt. Gen. Scott A. Spellmon, in his role as chief of the U.S. Army Corps of Engineers, which awarded a federal a permit to NISP in 2022.

In the lawsuit, filed Thursday, Save The Poudre says the diversion of water from the Poudre River would cause severe damage to the river, including its aquatic life, the Poudre River Whitewater Park in Fort Collins and the riparian corridor.

"In some months and years, NISP would divert 65% of what water is left in the river, which is already heavily diverted by farms and cities," a Save The Poudre news release announcing the lawsuit states.

The lawsuit also alleges that in approving the permit, the Army Corps violated both the National Environmental Policy Act and the Clean Water Act because it didn't adequately consider alternatives and didn't choose the least environmentally damaging alternative, respectively.

"Throughout the nearly 20 years of the federal permitting process, NISP claimed that it required 40,000 acre feet of water, and thus screened out many smaller and less environmentally damaging alternatives that could’ve met the needs of the participants, including conservation alternatives proposed by Save The Poudre," the news release said.

In response to the lawsuit, Northern Water issued a statement: “Northern Water has not had the opportunity to explore the issues brought forth in the action against the federal government, but we are confident in the thorough work performed by the Army Corps of Engineers that the permit issued to NISP will be affirmed based on the detailed work done over the years and extensive mitigation being included.”

NISP would divert water from the Poudre and South Platte rivers to store in two new reservoirs: Glade Reservoir north of Fort Collins and the smaller Galeton Reservoir east of Ault. Communities that would be served by the project include the Fort Collins-Loveland Water District and others in Weld and Boulder counties.

The project is estimated to cost more than $2 billion.

On its website, Northern Water says NISP would increase water flows in the Poudre River during drought periods.

"Water will be strategically released from Glade Reservoir throughout the year every year, which will help improve flows in the Poudre River even during droughts," the website says in a page labeled "Fact vs. Fiction."

Northern Water also says NISP will improve water quality in the Poudre, "in particular with respect to reducing temperatures to improve river health."

"In places where independent experts and scientists identified negative impacts, Northern Water has made commitments to address the impacts," the website states.

Save the Poudre also sued Larimer County over its approval of a permit for NISP, and it sued the city of Fort Collins over its earlier review of the project using what is known as a SPAR process.

Since then, Fort Collins adopted a "1041" review process for projects like NISP that touch the city's natural areas. So, NISP will now have to go through that process.

This article originally appeared on Fort Collins Coloradoan: Save The Poudre sues Army Corps over NISP water project