Project Profile: St. Mary’s Glacier Water and Sanitation District Water System Improvements
Idaho Springs, Colorado
The CGRS Water/Wastewater Services team recently completed the first phase of a $3.4 million water system improvement project for St. Mary’s Glacier Water and Sanitation District, north of Idaho Springs.
The total scope of the project over two building seasons includes:
- Installation of 3,100 lineal feet of 4” water line
- Installation of 400 feet of 8” gravity sewer piping and two manholes
- Installation of two pressure-reducing valve (PRV) vaults
- Construction of a new, two-story booster pump station
- Repairs and improvements to an existing water storage tank
- Construction of a new well house
- Extensive electrical upgrades in existing well houses and new electrical and automation systems in the booster pump station
Because the site elevation of over 10,000 feet and Clear Creek County requires all work in the road right-of-way cease after Oct. 31, CGRS will remobilize in late spring/early summer 2021 to finish the project.
In fall 2020, CGRS installed 1,400 feet of the 4-inch water transmission line from the District’s water supply wells to the existing concrete storage tank on Alice Drive. The team faced many challenges, including:
- Permit delays
- Weather delays
- Unexpected bedrock conflicts
- Roadway subbase material consisting of tree roots and topsoil
- Scarce and non-existent utility locates creating unexpected conflicts and field-alignment changes and
- Ongoing design changes
“The CGRS team approached issues through a complementary and collaborative relationship with the District, operators and design engineer,” said Greg Steed, CGRS Project Manager. “The regular and ongoing dialogue on this project – or for any complex project – has been the essential element for successfully addressing the challenges.”
To address the various obstacles, the CGRS Water/Wastewater team:
- Modified the project schedule and phasing plan to tackle portions of the scope that were best defined;
- Created revised and ongoing pipeline re-routing suggestions for engineer review;
- Used a two-month rental of a potholing vacuum truck to locate utilities;
- Hired a private locate service, combined with District efforts, to locate service lines and curb stops;
- Slowed excavation work where utilities were suspected but unknown; and
- Worked on a daily basis with the water system manager, who helped to predict utility conflict areas, and when utility breaks did occur, coordinated with customers as CGRS expedited repairs.
“The CGRS management staff continues to work closely with the engineer on design revisions, constructability and cost change management,” Steed said.
He noted that COVID restrictions have become the new normal for construction practices, including meeting virtually. Those on the job site attend those meetings at the Alice School House, where they can maintain social distancing. All field and office staff practice social distancing and wear masks when within 6 feet or in enclosed spaces.
The main components of the remaining work include completion of the 4” transmission mains, and construction of a new booster pump station, a new water well treatment house and two pressure-reducing valve vaults.
“We are expecting challenges in the Phase 2 spring start with high groundwater due to snowmelt runoff, as well as continued utility and bedrock conflicts,” Steed said. “The short building season presents challenges to phase, sequence and schedule the remaining work for completion in November.”
Once CGRS completes the project, District customers should see a more reliable and sustainable water system with reserve water storage for fire flows.