The Minneapolis Central City Tunnel System Project involved enlarging part of the Chicago Avenue Parallel Storm Tunnel and construction of a new stormwater tunnel parallel to the existing one. The project required a U.S. Army Corps of Engineers permit, triggering compliance with Section 106 of the National Historic Preservation Act, as well as state laws including the Minnesota Historic Sites Act, Field Archaeology Act, and Private Cemeteries Act.
Scope
Prior research by 106 Group identified several features within the construction area related to the Palisade Mill site, a contributing property to the National Register of Historic Places (NRHP)-listed St. Anthony Falls Historic District (SAFHD). 106 Group prepared a monitoring plan and Unanticipated Discovery Plan (UDP) outlining procedures for archaeological monitoring and a framework for evaluating and treating any discoveries during construction. A total of eight archaeological features were documented, all recorded as components of the Palisade Mill site due to their historical association and proximity to the mill, which contributes to the NRHP-listed SAFHD.
Outcome
The monitoring plan and UDP received swift approval, allowing construction to proceed without delay. When unexpected discoveries arose, we quickly secured agency approvals to implement treatment measures, minimizing disruption and keeping the project on schedule. The project was recipient of a Grand Award from the American Council of Engineering Companies of Minnesota.
