Iowa raised its rural statutory default speed limit from 55 to 60 mph, taking effect on 1 July 2026 (Code 321.285(3)). Only paved roads move to 60. And 60 is a default; posted-lower limits still apply and signs are going up gradually.
I’ll update the Default speed limits wiki page after July 1. But there are also a few thousand rural Iowa segments tagged maxspeed=55 that look like the old default rather than surveyed postings. I’d like input on whether it’s worth updating the clearly-paved ones (n = 1,696) to 60 mph, scoped tightly:
- currently maxspeed=55 mph
- highway unclassified through trunk (no motorway; residential included since rurally it’s a de-facto minor road, not a 25 mph residence district)
- surface = asphalt/concrete/paved. Excludes unpaved and unknown
- US Census rural areas only (imperfect, I know)
- source:maxspeed is not “sign” and maxspeed_type is not “sign”
Rather than just flipping numbers, I’d dual-tag: maxspeed=60 mph + maxspeed:type=US-IA:rural, so it’s clearly default-derived and self-documents for the next change. (Iowa has no implicit tagging yet; US-IA:rural follows the legal-default-speeds library)
The risk: we can’t tell from the data which 55s are genuine postings that will remain effective, versus old defaults. Speed limit data sources for Iowa are almost never explicitly tagged; I only found 14 instances of otherwise-eligible ways, compared to the remaining 1,696 I mentioned)
Would it make sense to go forward with this 60 mph change for the overall benefit, or leave as-is and wait for local knowledge to hopefully trickle in?
Edit - forgot to add this initially: Disclosure: I currently work at Geotab and handle the backend speed limit data behind fleet speeding alerts, so I have a professional interest - but we can handle this internally and I don’t need the OSM change. My motivation is that if these edits are valuable, I’d like to contribute them back. If it goes ahead I’ll put up an Organised Editing Activity page.)