As of last Thursday, based on a press release from the city of Cedar Rapids, a devil’s circle roundabout has opened downtown at Mount Vernon Road SE/10th Street SE/8th Avenue SW. This intersection is where the “cutoff” for the Lincoln Highway turned from Mount Vernon Road to 10th Street and then, between 1940 and 1953, US 30 turned from Mount Vernon Road to 8th Avenue. The bridge built for that alignment of 30 is the one scheduled to be replaced by the end of the decade (maybe).
While I strenuously oppose the widespread use of roundabouts, there are occasional places they might make a tiny bit of sense, and non-perpendicular intersections constitute one of those places. However, the city of Cedar Rapids is going roundabout-crazy and announced nearly a dozen of them in 2023. This one, along with what was a four-way stop at Wilson Avenue and Bowling Street SW, was on that list.
Another on that list, which hasn’t started yet but should in the near future, is Johnson Avenue NW and 18th Street NW. The city’s project page links to both the slides and fact sheet are 404’d, but there is a YouTube video that goes through the slides. The video is two years old, and said things would happen in 2025, but it’s the middle of summer and nothing has happened yet. We should probably believe the project page that says construction won’t happen until 2026.
Anyway, the key here is not necessarily that the intersection of Johnson and 18th is going to become a roundabout, but that B Avenue west of 18th Street will be turned into a cul-de-sac. In 1930, 18th Street was the west city limit of Cedar Rapids, and building a B Avenue extension was an Iowa Highway Commission project as part of realigning US 30 through the city in 1931. US 30 was then taken off B in 1938.
The intersection of 18th and Johnson became a four-way stop in 2020, and at the same time just to the north, interestingly enough, 18th became the through street instead of B Avenue, which used to be US 30.