Sewers, drains and steam tunnels…oh my!

Unseen by passersby, a machine called a road-header is at work 20-hours a day near the future TCF Bank Stadium. It is 80 feet beneath street level, grinding its way through a layer of sandstone, extending the University of MinnesotaâÄôs steam tunnels toward an area of new development near the stadium. The steam tunnels are by far the deepest, but there are several other infrastructure projects going on under the eastern edge of campus. Projects include the tunnels, the creation of a storm water pond and a change to the sewer system, which is currently disrupting traffic on University Avenue.

Steam Tunnels

A reliable source of steam for heating and some research applications is very important for a lot of the newer buildings, said Mike Nagel, Facilities ManagementâÄôs assistant director for utilities. The Southeast Steam PlantâÄôs multiple boilers and staff provides steam to the entire Minneapolis campus. Initially, the University wonâÄôt need to add boiler capacity to deal with the buildings that will connect to the new steam tunnel, he said, but in its two-year master utility plan, his department will recommend that the University add boilers to deal with additional planned buildings. The only above-ground sign of the steam tunnelâÄôs progress is the excavation for the elevator building, across University Avenue from TCF Bank Stadium, which University project manager Kevin Ross said will provide access to the tunnels.

Storm Water Holding Pond

The elevator building will share the western end of its lot with a storm water holding pond, which will slow runoff from TCF Bank Stadium and the rest of the East Gateway District, Brian Swanson, the UniversityâÄôs manager for the project, said. Surging water during storms is hard on storm drains and bad for the river, he said. This pond will reduce the impact on both. Water will be collected at several âÄúbioswales,âÄù which Swanson described as landscaped low areas functioning as both filters and storm drains. Water from these âÄúbioswalesâÄù will be collected into two pipes running under University Avenue and into the pond. Swanson said the two pipes will fill the pond quickly after rainfall, before draining slowly through a single drain pipe and into the river.

Sewer

Traffic on University Avenue near Williams Arena was increased from one lane to two Sunday, as work on a Metropolitan Council sewer project progressed, allowing cars to drive on both sides of the hole in the center lane. The project will both increase the sewerâÄôs capacity and allow the council to abandon an obsolete sewer line, said Sarah Hache, the Metropolitan CouncilâÄôs construction inspecto r. The old pipe is inside a 96-inch storm drain, and because of the risk of contamination, the Metropolitan Council is getting rid of them, the UniversityâÄôs project manager Ross said. The hole in University Avenue and the other holes in front of Williams and Mariucci arenas access a point where sewer lines feed into the old pipe. Crews will be tunneling from those points out to a larger diameter sewer pipe the council has already buried under Oak Street. Then theyâÄôll disconnect from the old pipe and connect to the new, larger pipe, Hache said. Ross said that portion of University Avenue will have two lanes open until May 1, when it will go back down to one lane, before reopening fully in June. Despite efforts to redirect fan parking, the traffic after basketball and hockey games was bad enough that the University decided to employ police officers to direct traffic, said Scott Ellison, the athletics departmentâÄôs associate director for facilities .