Sometimes better information throws your settled pattern for a loop.
Part of what I have stated on this website for IA 3’s history in Dubuque is wrong. The maps never would have distinguished the difference, but the online route description, made available in 2016, does. The state highway never ended at US 61/151 before the present-day expressway/freeway was built, according to the route description; its end was officially US 20 from at least 1948 until 1991.
But … that’s a direct contradiction of the primary road sufficiency logs, which I used as the basis for my IA 3 history. How do I solve this? Well, I can’t, unless someone in Dubuque happens to have 20th-century photos of the relevant intersections. I can, however, note the discrepancies.
It makes a mess of some maps I had though. The bright side is, with the route descriptions for US 20, 52, 61, and 151, plus some sleuthing in what’s available online for the Dubuque Telegraph Herald, I believe I have been able to reconstruct an accurate history of the highways in Dubuque with just a couple of ambiguities.
The Dubuque Highway Chronology is different from others I’ve done because the map covers a relatively small area, downtown. The rest of changes in the metro are mentioned but I felt any bigger size took away from where the important stuff was happening — especially since so many maps are needed.
The corrections come right up to the present day. I didn’t think that the conversion of certain streets in downtown Dubuque to two-ways in 2014 affected US 52/IA 3, given the exit configuration on US 61/151, but I was wrong on that too (and really should have fixed it earlier since I did get a PowerPoint from the DOT about it). It’s actually kind of funny because it’s resulted in a transfer of jurisdiction of one lane but not the other of a city street (11th). The east end of IA 3 is where it has been, on 9th Street, but the west beginning technically is 9th now too.
Now, with all the changes, I was afraid I wasn’t going to have good pictures of points I needed. I still kind of don’t BUT I was able to pull from 2007, 2013, 2015, and 2016 to augment not just IA 3 but US 20.