Bridge construction was delayed over Grand River flooding in spring 2013 . In 2014 , the new interchange at I-96 was completed . The steel beams spanning the river were not set in place until August 2014 . MDOT announced in August 2015 that they would hold a " M23 .1 k Run " on October 3 , 2015 , before the highway opened to traffic . The agency limited participation to 231 runners . The highway opened to traffic on October 30 , 2015 , and the total cost for M-231 was estimated at $ 180 million
Grand River flooding in spring 2013
2013 Grand Rapids flood
M-231 (Michigan highway)