Minneapolis Planning Central City Parallel Storm water Tunnel

The Minneapolis Department of Surface Waters and Sewers is planning to build the Central City Parallel Storm water Tunnel in downtown of the city.
The tunnel is a sandstone bedrock one, and it is going to be nearly 4,300 ft. long and range in size from 9.75-ft to larger than 12-ft equivalent diameter. The project is valued at 50-60 million USD.

The tunnel will pass into a channel neighboring the Mississippi River at the same location as the existing tunnel outlet.

The tunnel will help over pressurization in the undersized parallel existing tunnel system.
The construction will start in fall 2021, and the Bidding Documents will be available late spring 2021.