text: business routes of u.s. route 31 in michigan there have been seven business routes of us highway 31 in the state of michigan . all of the business routes are former sections of us highway 31 ( us 31 ) . they connect the freeway mainline of us 31 to the various downtowns of cities bypassed by us 31 . two of the current business routes , for hart and ludington , are business spurs , connecting to us 31 on only one end , while the remainder for muskegon , whitehall – montague and pentwater , are business loops . the two former routes , for niles and holland were a business spur and loop , respectively . niles business us highway 31 ( bus . us 31 ) was a business spur running to the niles downtown area along a former routing of us 31 from us 31 exit 7 ( walton road ) northeasterly then southeasterly into downtown , ending at bus . us 12 at the corner of front and main streets . at the time it was decommissioned , bus . us 31 was only designated along the north – south segment between walton road and main street . it was commissioned in 1987 as a loop connecting to us 31 on both ends , running along us 12 to us 33 ( 11th street ) north into downtown and along bus . us 12 . bus . us 31 followed front street northward back to the mainline us 31 at walton road northwest of downtown . the business loop was extended along walton road in 1992 when the next segment of the us 31 freeway opened in berrien county . the highway was truncated to a spur route in 1998 when m - 51 was extended southward . the northernmost remaining portion along walton road was turned over to the berrien county road commission on october 23 , 2007 , and the remaining portion was replaced by an extended m - 139 in april 2010 . major intersections the entire highway was in berrien county . holland business us highway 31 ( bus . us 31 ) was a 4 . 1 - mile - long ( 6 . 6 km ) business loop running through holland . it started at an interchange on the southern edge of the city where business loop interstate 196 ( bl i - 196 ) , us 31 and a - 2 all converged near west michigan regional airport . bl i - 196 turned northward off the us 31 freeway and ran concurrently with bus . us 31 along washington avenue through a residential area on the southern side of holland in allegan county . at the intersection with 32nd street , bl i - 196 / bus . us 31 crossed into ottawa county and turned northeasterly on michigan avenue . michigan avenue ends at an intersection with state street and 19th street , and the business loop turned due north on river street into downtown . the business loop split along the one - way pairing of 7th and 9th streets in downtown . the northbound direction ran eastward on 9th street while the southbound direction was routed two blocks north on 7th street . on the eastern side of downtown at lincoln street , southbound traffic was routed on 8th street . , and one block further east , both directions followed 8th street . at chicago drive , bl i - 196 / bus . us 31 turned northeasterly to follow that street out downtown . bus . us 31 ended at an interchange with us 31 in holland township while bl i - 196 continued northeasterly on chicago drive . the initial bypass of holland , rerouting us 31 out of downtown opened in 1954 . the former routing through downtown was redesignated as bus . us 31 at this time . the first segment of i - 196 / us 31 freeway in the holland area opened in 1963 , adding an interchange to the southern terminus of bus . us 31 . in 1974 , the i - 196 bypass around holland was completed , and chicago drive east of us 31 becomes a business route for i - 196 . by 1976 , this business route was extended along bus . us 31 through downtown as well . in 2004 , all of bus us 31 was decommissioned and bl i - 196 was rerouted to follow us 31 around downtown . major intersections muskegon alternate route us highway 31a ( us 31a ) was an alternate route through muskegon . the designation was first commissioned in 1932 for a highway that bypassed downtown muskegon to the east . in 1940 , the alternate route and the mainline highway were flipped through the area , rerouting us 31a to run through downtown . at the same time , us 16 was rerouted to run into muskegon , partially following us 31a . this last version of us 31a ran northwesterly along airline highway and peck street into downtown , where us 16 turned westward along m - 46 . us 31a continued northeasterly along muskegon avenue back to us 31 at marquette avenue . a year later , the alternate route was redesignated as business loop instead , removing the us 31a designation from the state highway system . major intersections the entire highway is in muskegon county . muskegon business loop business us highway 31 ( bus . us 31 ) is a 9 . 87 - mile - long ( 15 . 88 km ) business loop running through the muskegon area . it starts in norton shores and an interchange with us 31 as the westward continuation of interstate 96 ( i - 96 ) and continues as a freeway for about a mile ( 1 . 5 km ) before downgrading to an expressway with michigan left turns near the muskegon county airport . the business loop runs along the southern edge of muskegon heights and then turns northward near the roosevelt park city line . this north – south segment forms the boundary between commercial properties to the west and residential neighborhoods to the east as far north as the intersection with broadway avenue . north of sherman avenue , the business loop crosses into the city of muskegon and runs through commercial properties on seaway drive . as it approaches muskegon lake , bus . us 31 turns northeasterly along shoreline drive , running around the northern edge of downtown . on the northeastern corner of downtown , the business loop turns sharply northeasterly along moses j. jones parkway . along this parkway segment , bus . us 31 meets the southern terminus of m - 120 and turns easterly along a freeway segment in muskegon township to terminate at us 31 . the first bypass of muskegon opened to traffic in 1932 to the east of downtown ; it was designated us 31a . this first alternate route and the mainline were flipped in 1940 , routing us 31a through downtown ( partially along a section of us 16 ) and us 31 along the bypass . in 1941 , us 31a was redesignated bus . us 31 . the business route was extended on each end in 1950 or 1951 when the mainline was shifted further out of the city to the east . at the end of the 1950s , the us 31 bypass east of muskegon was converted to a freeway , and the southern section of the business loop was rerouted to follow seaway drive . when us 16 was decommissioned in the state in 1962 , the section of us 16 / bus . us 16 is redesignated bs i - 196 , and the following year , it becomes bs i - 96 ; bus . us 31 remains in place through both changes . the northern end of the business loop near downtown was rerouted onto the one - way pairing of muskegon and webster avenues in 1965 . in 1984 , the bs i - 96 designated into muskegon was decommissioned . the northern section of bus . us 31 near downtown was rerouted again , this time to follow shoreline drive , in 2007 . major intersections the entire highway is in muskegon county . whitehall – montague business us highway 31 ( bus . us 31 ) is a business loop running through whitehall and montague . it starts at an interchange with us 31 in whitehall township east of the city of whitehall and runs westward on colby street past a cluster of businesses . farther west , bus . us 31 runs through residential areas before entering downtown whitehall and turning northward on thompson street to cross the white river near its mouth on white lake . on the northern side of the river , the business loop follows dowling street in montague and then turns north - northeasterly on water street through downtown . bus . us 31 exits downtown and passes through a residential area before leaving montague . north of town , the business loop runs past various businesses and next to farm fields to an intersection with b - 15 ( fruitvale road ) in montague township . the business loop turns eastward and runs concurrently with the county highway for a short distance to an interchange with us 31 that marks the northern terminus of the business loop . a freeway bypass of whitehall and montague opened in 1964 , and the former routing o us 31 through the downtowns of the two cities was redesignated bus . us 31 . at the northern end , the routing split to follow two connections with the new freeway , running east on fruitvale road and running north on whitehall road . b - 15 was designated in 1970 , overlapping the business loop at the northern end . the bifurcated northern connection to the freeway was removed in 1975 when the next segment of us 31 opened heading north into oceana county . major intersections the entire highway is in muskegon county . hart business us highway 31 ( bus . us 31 ) is a 2 . 1 - mile - long ( 3 . 4 km ) business spur running into the hart downtown area . it starts at exit 149 on us 31 in hart township and runs eastward along polk road into the southern part of the city . the business spur passes some commercial properties along polk road before turning northward on state street next to the oceana county fairgrounds . bus . us 31 passes more businesses before entering a residential area . the business spur terminates at the intersection with johnson street in hart . a segment of us 31 freeway opened from the polk road interchange northward to monroe road southeast of pentwater in 1978 . at that time , us 31 was rerouted out of hart . the former routing along polk road and state street was designated as bus . us 31 in 1987 . major intersections the entire highway is in oceana county . pentwater business us highway 31 ( bus . us 31 ) is a 7 . 2 - mile - long ( 11 . 6 km ) business loop running through the pentwater downtown area . it starts at an interchange on us 31 in weare township southeast of pentwater . it runs westward and northwesterly along monroe road and across the pentwater river through a rural wooded area . the business loop intersects b - 15 at that county highway 's northern terminus in pentwater township on the shores of pentwater lake . the business loop follows the northern shore of the lake and then turns west on 6th street through a residential area into the village of pentwater . in downtown , bus . us 31 turns northward along hancock street . the business loop exits downtown and passes through another residential area on the north side of the village before exiting town northeast of charles mears state park . bus . us 31 meanders through rural woodlands north of pentwater as it approaches the oceana – mason county line near bass lake . the business loop turns eastward , briefly following the county line before turning southeasterly to an interchange with us 31 on the pentwater – weare township line . us 31 was rerouted to run further east of pentwater in 1955 , and the former route through the village was redesignated as bus . us 31 at that time . in 1978 , a section of us 31 freeway opened between hart and pentwater . bus . us 31 was slightly truncated on its southern end to terminate at the new freeway interchange , and part of monroe road was redesignated as the mainline of us 31 between the end of the freeway and the former routing of us 31 . the next freeway segment opened in 1980 , and bus . us 31 was slightly lengthened to connect to the new freeway interchange with oceana road . ] , resulting in the current configuration . major intersections ludington business us highway 31 ( bus . us 31 ) is a 3 . 2 - mile - long ( 5 . 1 km ) business spur running into the ludington downtown area . the highway starts at exit 166 on the us 31 and follows pere marquette highway northwesterly and northward toward ludington . the business spur crosses the pere marquette river near pere marquette lake . north of the river , bus . us 31 passes through an industrial area on the edge of ludington in pere marquette township . the business spur terminates at an intersection with us 10 east of downtown . ludington was bypassed in 1989 with the extension of the us 31 freeway in mason county . the former route of us 31 along pere marquette highway north of the freeway was retained as an unsigned highway . in 2005 , it was designated as bus . us 31 . major intersections the entire highway is in pere marquette township , mason county .