Interstate 375 Michigan

Interstate 375 comprises a short spur extending the Walter P. Chrysler Freeway south from I-75 to the Detroit Riverfront in Downtown Detroit. The six lane freeway travels below grade between service streets to Jefferson Avenue, where it turns west and transitions into a surface boulevard at Beabien Street. Unsigned Business Spur I-375 overlays Jefferson Avenue 0.167 miles west to Randolph Street by the GM Renaissance Center.

Showing signs of age, studies were underway on how to address future transportation needs for Detroit when it came to Interstate 375. Six options for I-375 were outlined in 2014, ranging from rebuilding the freeway as a below grade expressway or converting it to a surface boulevard. Costs estimates ranged from $45 million to $80 million for design and construction on the various options. A lack of consensus among city leaders, planning agencies and major property owners by January 2016 led to an indefinite delay on any recommendation of the aforementioned options. Instead the Michigan Department of Transportation (MDOT) continued repairing overpasses and maintaining I-375 as it was.¹

Plans to convert I-375 into a surface boulevard resumed and MDOT narrowed the options to two alternatives for a four-lane surface boulevard between Gratiot Avenue and Atwater Street by December 2017.⁴ The Recommended Preferred Alternative at the December 13, 2018 advisory committee meeting outlines a six to seven lane at-grade boulevard with signalized intersections, bike lanes, a series of crosswalks and a 35 mile per hour design. The interchange at I-75 and I-375 will be removed and new ramps built above a realignment of I-75. Construction for the I-375 Improvement Project is planned to start in Spring 2027.

Condition to approval by the Federal Highway Administration (FHWA), the American Association of State Highway and Transportation Officials (AASHTO) approved the elimination of Interstate 375 at the Spring 2021 Meeting.

The elimination of the I-375 route designation in Michigan will be effective upon the removal of the facility, which is currently estimated to be in 2027.

The proposed Urban Interstate System for the state of Michigan submitted to the American Association of State Highway Officials (AASHO) on August 15, 1958 included I-275 for a proposed loop into Downtown Detroit. Due to a changes made in the route of Interstate 75, the recommended loop number 275 was deleted, and recommended for reassignment to the west bypass of the Detroit Area in place of 294. This was conveyed by the Michigan State Highway Department to AASHO on September 12, 1958.

Interstate 375 was constructed at a cost of $50 million and opened to traffic in 1964.¹ I-75 defaulted from the Chrysler Freeway south onto Interstate 375 between November 25, 1964 and 1968. Opening at that time was the Fisher Freeway west from Gratiot Avenue (former U.S. 25) and I-375 to 12th Street.²

When U.S. 10 was truncated from Detroit northwest to Bay City in 1986, it was redesignated as M-10 along the John C. Lodge Freeway north from Interstate 75 and Business Spur I-375 south from I-75 (Fisher Freeway) to Jefferson Avenue at Downtown Detroit. Sign changes were slow to follow however, and the business spur portion of old U.S. 10 ended up signed as part of the Trunkline Highway instead.³