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Project Overview#
Halligan Reservoir is an existing reservoir on the North Fork of the Poudre River, 25 miles northwest of Fort Collins.
If approved, the Halligan Water Supply Project will enlarge Halligan Reservoir by approximately 8,200 acre-feet to meet the demand of future Fort Collins Utilities' water customers and provide increased reliability for existing customers to help protect against service interruptions related to prolonged drought and emergencies.
The project will help:
- Provide a storage reserve for emergency water supply
- Increase drought security
- Improve water system reliability and flexibility
- Meet future water demands of the Fort Collins Utilities' water service area
The U.S. Army Corps of Engineers (Corps) released a draft Environmental Impact Statement (EIS) in November 2019. The Corps will develop a final EIS before making a permitting decision on if Halligan Reservoir can be expanded.
Updates#
2021 Year In Review
From state and federal permitting to preliminary design work and dam concepts– see what was accomplished in 2021.
Potential New Dam Concept Identified
Preliminary design efforts revealed that two viable dam concepts exist for enlarging Halligan Reservoir.
City Council Quarterly Updates
Find the past and present City Council quarterly updates here.
2021 Year In Review
From state and federal permitting to preliminary design work and dam concepts– see what was accomplished in 2021.
Potential New Dam Concept Identified
Preliminary design efforts revealed that two viable dam concepts exist for enlarging Halligan Reservoir.
City Council Quarterly Updates
Find the past and present City Council quarterly updates here.
Explore Halligan Reservoir#

Halligan Reservoir spilling over the existing dam in spring.

Halligan Reservoir north shore.

Existing Halligan dam.

Existing Halligan dam and North Fork of the Poudre River looking south west.

North Fork of the Poudre River looking south downstream of Halligan Dam.

Halligan Reservoir in the spring.

Aerial view of Halligan Reservoir.

Halligan Reservoir in the spring.

Halligan Reservoir and existing dam.

North Fork of the Poudre River downstream of Halligan Dam, looking north.

Top of Halligan Dam looking south.

Water spilling over Halligan Dam in the spring.

The Halligan Reservoir shoreline.

Halligan Reservoir inlet.

Halligan Reservoir.