Iowa Highway Ends (etc.)

The Iowa DOT says that Olde Davenport Road’s connection to US 61/151 will be closed permanently this week, and a month later, the new interchange between 61/151 and the Southwest Arterial will open.

(The Southwest Arterial itself, however, will not open until next summer, as KCRG reported much earlier.)

Olde Davenport Road, by its name, likely was the original main route between Dubuque and Davenport. However, what sources I have indicate that it was falling out of favor by the early 20th century. Future US 61 did not use it.

The 1912 Huebinger county map collection makes Olde Davenport Road the primary route heading south out of Dubuque, through La Motte, then forking with the main branch going through Fulton and an alternate through Andrew to Maquoketa. But a scant two years later, the official state county road system map drops Olde Dubuque Road in favor of a route going straight north from Maquoketa through Zwingle to join the diagonal from Cascade in the little village of Key West. This intersection was still under state maintenance until 2003, as part of IA 955 and IA 963, and served as the north end of US 161 in 1926-38.

More recently, the Key West Drive name (Key West now being incorporated into Dubuque) had usurped the Olde Davenport Road name for the three-quarters of a mile between that old intersection and the present-until-Wednesday one with 61/151. The new folded-diamond interchange will be to the south; the present intersection is about where the southbound exit/northbound entrance ramps meet the mainline.

I admit I don’t have much past that, just that Olde Davenport Road is old, so old that it was already considered the old route a century ago.

The first segment of interstate highway to open in Iowa was not signed as an interstate highway.

Recent research from Jason Hancock has revealed that when the Combination Bridge interchange in Sioux City opened at the end of 1957, there were no I-29 shields, just US 20 and US 77. The new pavement went west to Hamilton Boulevard (which, at the time, was an extension of Isabella Street), where it stopped for about 10 months until the entire riverfront four-lane to IA 12 opened.

That means the concrete from the Hamilton Boulevard area that started to be removed last month (see the KMEG story embedded above) is more than 60 years old. I’m surprised it remained there all this time, but then, other locations in Iowa have much older concrete on lesser-traveled roads.

After considering the possibilities for upgrading the two-lane stretch of US 30 between Lisbon and De Witt, the DOT appears to be settling on…a two-lane stretch of US 30 between Lisbon and De Witt.

In a public meeting on the planning study last week (handout) (large PDF), the future for this corridor will be a Super-2. This is a regular two-lane road with frequent passing lanes. The rebuilt US 169 between Humboldt and Fort Dodge is a recent example. The only segment that might be relocated later is the diagonal past Mechanicsville, which I think should be a grade-for-four-pave-for-two if not an outright extension of the four-lane opening this year.

The Clinton County supervisors are furious at this outcome.

Or, contra my post from May 2018, Wapello bypass plans UN-finalized. It appears I jumped the gun.

Completion of the last four-lane stretch of US 61 in Iowa outside Keokuk has been notable for the unwillingness of the two towns along the route, Mediapolis and Wapello, to take the state’s offer of only one interchange access point.

In the latest wrinkle, as reported by the Burlington Hawk Eye, the DOT proposed a “slip ramp” at the south end of the Wapello bypass. Instead of a dead end at the point the four-lane leaves the existing road, there would be a northbound-off southbound-on pairing. At the same time, two gravel roads would be severed along the bypass route and one road that was going to be closed will instead get a bridge, differences from the December 2017 EIS and May 2018 plan.

The city tried to one-up the half-a-loaf compromise by offering to pay for a full diamond interchange, but the state won’t allow it.

Look closely and you can see that the proposed four-lane is the third routing of US 61 south of Wapello. Besides the current road, the curves on J Avenue just to the east give away that that was used until 1932. It’s fitting, in a way, that the last part of original US 61 to be paved will be the last part to be four-laned about a century later.