Phase 2 includes constructing a parallel pipeline from the area of Valmont Rd and Butte Mill Rd to the WRRF located near 75th St and Jay Rd. A new inverted siphon will be constructed north of the WRRF to better serve the Gunbarrel community.
The upgraded systems will convey the majority of the city’s wastewater to the WRRF through a location away from Boulder Creek. Portions of the existing system will remain in place to support flows from North Boulder, as well as provide a redundant asset for this key area of the wastewater collection system.
Length: 2.5 miles
Diameter: 42 and 54 inches, dependent on location
Installation methods: Primarily open cut construction, with 2,000 feet of tunneling in bedrock in Valmont Road between Butte Mill and 61st St. Tunneling was selected for this area to minimize impacts to Valmont Rd. traffic and private wells for the Valmont community.
- Seasonal closures of trails within Sawhill and Walden Ponds for construction. Construction timing in sensitive areas were coordinated with USACE, US Fish and Wildlife Service, Colorado Parks and Wildlife, City of Boulder OSMP and Boulder County Parks and Open Space to minimize impacts to users of these spaces, as well as around a seasonal closure for a nesting osprey nest in Sawhill Ponds.
- Increased construction traffic on Valmont Rd, Butte Mill Rd, and 61st St. While the project is designed to minimize road closures in this area, there will be increased traffic for construction activities.
- Lane closures on Jay Rd, west of 75th St for inverted siphon construction.
- Impacts to individual property owners, coordinated with each property owner through easement acquisition process.
Please check the city's Cone Zones for current traffic impacts, the city's trail closures webpage for impacts to Sawhill Ponds trails, and Boulder County's trail closures webpage for impacts to Walden Ponds trails.