Public Hearing on tunnel rehabilitation planned May 22

Metropolitan Council Environmental Services (MCES) held a public meeting Apr. 24, is currently in a comment period, and will sponsor a May 22 public hearing on plans to rehabilitate sewer infrastructure in the area of Minnehaha Regional Park.

According to the Met Council, the work needs to be done to protect the integrity of the infrastructure. Earlier plans were modified to ensure the protection of the Coldwater Spring. Staff is meeting with neighborhood groups and conducting other community engagement.

The public hearing, where verbal comments will be recorded, will be held Tues., May 22, 6:30-8pm at the Hiawatha School Recreation Center, 4305 East 42nd St.

The proposed project is located on the north side of E. Minnehaha Pkwy., and the tunnel is located under Minnehaha Creek, Hiawatha Ave. and the METRO Blue Line light rail corridor. The existing tunnel is located 1½ miles northwest of Coldwater Spring, a significant cultural and historic resource.

The existing regional sanitary sewer tunnel, built in 1935, is in need of rehabilitation. MCES plans to clean the tunnel, install a liner that will create a new sewer pipe within the existing tunnel, and upgrade the existing regulator and electrical vaults. The proposed work will preserve the structural integrity of the tunnel and will minimize the risk of failure.

MCES previously planned to replace the tunnel and to start construction in 2017. Due to concerns expressed last year, MCES performed additional technical studies to better understand the groundwater flow connected to Coldwater Spring, and to determine if the existing tunnel could be rehabilitated rather than replaced. MCES has determined that the existing tunnel can, and should, be rehabilitated (rather than replaced) to avoid the potential for impacts to groundwater flow to Coldwater Spring.

The rehabilitation work that is now planned will start in 2019.

MCES is working with the Minnesota Pollution Control Agency (MPCA), as delegated by the US Environmental Protection Agency (USEPA), to determine which state and federal cultural resources requirements apply to this sewer rehabilitation project. MCES will continue to coordinate with tribes, neighborhoods and other interested parties as the project continues.