US 31: the Michigan Road under a number

1926–2014 · THE CITY STREET ERA

On 1 October 1926 the Great Renumbering made the old road a United States highway: The road south from South Bend had been State Road 1 — carrying, for a season, three designations at once: a 1925 auto-trails map shows the Rochester–South Bend stretch signed as State Road 1, the Dixie Highway (trail 25) and the Michigan Road (trail 26) together. The renumbering of 1 October 1926 made it US 31, and US 31 kept the Michigan Road's course: north through the city on Michigan Street, the road it had always been. Downtown, the highway's mature form was a one-way pair — Michigan Street carried it one way and Main Street the other, Main Street carrying US 31 south — with Michigan Street made one-way northbound in the late 1960s. The pair ran for a generation; a 2007 account of downtown still describes "Main Street and what is now Dr. Martin Luther King Jr. Boulevard" running one way, and the conversion of the pair back to two-way streets is the Smart Streets work told in this build's Government section, cross-referenced here and not re-litigated. In 1982 through traffic left the streets: US 31 moved onto the St. Joseph Valley Parkway, and the old course through downtown — Main and Michigan streets, and Cleveland Road at the city's north — was signed Business US 31. North of the city the old road kept climbing toward Michigan on its Dixie Highway line through Roseland and past the Toll Road; when the numbered system settled, that northern stretch took the state designation it still wears, State Road 933.

Sources:

1. The 1925 Rand McNally auto-trails mapping as reproduced in the road record — the triple designation of the Rochester–South Bend stretch: State Road 1, the Dixie Highway (trail 25), the Michigan Road (trail 26).
2. The Indiana highway designation record — State Road 1 became US 31 at the Great Renumbering of 1 October 1926; US 31 in northern Indiana follows the Dixie Highway line.
3. The road record for the downtown pair — original US 31 on Michigan Street as one half of a one-way pair with Main Street, which carried US 31 south; Michigan Street made one-way northbound in the late 1960s; Business US 31 created in 1982 along Main and Michigan streets and Cleveland Road when US 31 moved to the parkway.
4. Notre Dame Magazine (2007) — Main Street and the present Dr. Martin Luther King Jr. Boulevard still one-way in 2007; the two-way conversion is this build's Government section.