Iowa Highway Ends (etc.)

Security State Bank probably thought it had a swell deal with a high-visibility spot on four-lane US 151 at the new main entrance to Springville. A building opened in the northwest corner of the intersection with County Road X20 in 2005.

But with the completion of the four-lane to Dubuque, traffic on 151 increased substantially. For more than a decade, the intersection has been on the state’s list of most dangerous. A KCRG story from 2017 about one of the crashes said there had been 34 in seven years.

Nearly a decade ago, the DOT wanted to set up a J-turn — you may remember this term from when it was a possibility at the IA 330/US 65 intersection, and again when it was a possibility at the US 30/218 intersection. Indiana just started using it; it’s a close cousin of the “Michigan Left” except that a J-turn allows left turns from the dominant road. But it means that traffic from the intersecting road has to turn right, cut through two lanes of traffic moving at high speeds, and then merge from the left into other traffic moving at high speed. The technique has not appeared in Iowa yet, and every time it’s proposed it’s met with strong opposition.

Now, eight years after the state presented 16 alternatives for the 151/X20 intersection at Springville, the state … has completed the environmental assessment on an interchange. Three of the dismissed alternatives use a “parclo” setup which involves a loop ramp for northbound X20 to southbound (westbound) 151. But the DOT’s preferred option is a diamond interchange with that ramp going right through the existing Security State Bank building. The Casey’s next door would remain intact (or so I interpret).

There will be a meeting about the interchange, with a formal presentation, on March 12 at St. Isidore Catholic Church, which is right by the intersection.

The Springville intersection is likely the most important one between Marion and Dubuque that didn’t get grade-separation, because that part of 151 was four-laned earlier. But the situation there isn’t tenable anymore, and an interchange needs to happen.

The Council Bluffs and Sioux City interstate projects continue to plod along, and a big sign of progress is coming soon in Council Bluffs.

The Daily Nonpareil reports the Iowa DOT plans to open the westbound dual divided freeway for I-29/80 in early spring (assuming, as one must, that spring will come). This means there will be a clear shot from the Mall of the Bluffs exit across the Missouri River for I-80 with only the I-29 exit ramps in between. The state’s page, with a video I can’t embed, says the counterpart (eastbound 80/southbound 29) will open later in the year. See also this PDF. The Iowa DOT also has a “sponsored feature” online at the Omaha World-Herald that says the overall $1.6 billion, 15-year project is “on schedule and on or under budget.”

There is a safety valve of sorts: Each end of the dual divided freeway will have a ramp from Express I-80 to either direction of I-29. Nebraska is adding a lane to I-80 between 13th Street and US 75 on its side of the river.

The DOT’s Council Bluffs Interstate site has an “online meeting” that offers details about the upcoming year’s construction in the area.

It’s been more than half a century since County Road H34 from Hastings to Corning was US 34, but it’s still “old Highway 34” to the locals, and this spring it’s going to lose part of its old-ness.

The Red Oak Express reports that five miles of pavement on H34 will be widened from 18 to 22 feet, maybe starting as early as April.

The roadbed is probably unchanged from its original paving in 1928-30, given the quote from Montgomery County engineer Brad Skinner in the story. “If we took it down to a concrete road surface, we’d have to re-grade all the road sides, and bring it up to current grading standards,” he told the Express. That tells me the concrete-lipped “Iowa curbs” remain under the asphalt, and this project will overlay whatever remains visible today. It might also wipe out whatever shoulder is available, though.