20-inch Main Installation at 40th St & Blake St

Project Location: Denver, Colorado
Date Completed: September 2015
Methodology: Microtunnel


The project purpose was to replace an aging uncased cast iron water main originally installed in 1926, and to protect the existing railroad and recently constructed RTD light rail tracks. This was an important project to the community as it further supported expanding the right-of-way to the airport as part of the newly constructed FasTracks project. UIT installed over 400 LF of 36-inch steel casing undercrossing Union Pacific Railroad tracks, utilizing a microtunneling earth pressure balanced methodology (EPBM) through coarse and fine alluvium soils below the water table and with boulders up to 12-inch diameter. The tunnel was 22 feet in depth and utilized a slide rail shaft construction.