Around and around we go with Thursday 3 with the Iowa DOT

Thursday-Three_6Around and around we go for one of this week’s Thursday 3 questions. Each week we take questions from Facebook and Twitter and answer three of them on our blog. When you submit questions on Facebook or Twitter, use #Thurs3DOT to we make sure we get them. Our goal is to make the transportation system easier to understand, so if you have a question, please let us know.  


Q. Why are there so few roundabouts on Iowa’s state highways?

Roundabout_semi2 Iowa3-Iowa187 fayette county
This roundabout connects Iowa3 and Iowa187 in Fayette County.

A. In recent years, roundabouts have been used in the United States to reduce crashes, traffic delays, fuel consumption, air pollution, and construction and maintenance costs. Roundabouts often move more traffic and enhance intersection beauty. They have also been used to control speed in residential neighborhoods and are accepted as one of the safest types of intersection designs. 

That said, every intersection is unique. On the state highway system, roundabouts are just one of a host of options considered when an intersection is being reworked. Some of the factors we look at are the crash history of the intersection and the amount of available right of way.

The benefits of roundabout include:

  • Fewer crashes and less severe crashes
  • Lower vehicle speeds
  • Fewer vehicle delays
  • Less vehicle pollution
  • Lower maintenance costs as compared to a traffic signal
  • Increased landscaping opportunities
  • Pedestrians cross one direction of traffic at a time

While many cities and counties have constructed roundabouts on their road systems, there are currently only seven roundabouts on the state highway system. The first was built in 2006 at the junction of U.S. 34 and U.S. 63 near Ottumwa in Wapello County. The most recent was construction at U.S. 30 and Iowa 1 near Mount Vernon in Linn County.

For more details on Iowa’s roundabout program, go to

Q. Why is the construction zone on I-80 in Jasper/Polk County so long (distance) and lasting for such a long time?

A. This is a nearly $11 million shoulder reconstruction project from Polk County Road S-14 (exit 143) east to Iowa 117 (exit 155). Guardrail and culverts in the project area will also be repaired.  The contractor is currently working on stage two of the project. Once they finish the westbound shoulder reconstruction, they will work on the eastbound shoulders. The project is about 1/3 complete.

The paved shoulders in this area have failed and need to be replaced. Due to the drop off involved with this type of work, temporary barrier rail has been placed to protect both the workers and travelers.

The project is scheduled to be completed Nov. 25, 2015.

Additional info about the project is here:

Q. I have been wondering if it Park-and-ridepossible to allow licensed and insured private operators to run passenger non-stop shuttle services between park and ride locations in Ames and Des Moines.

A. We do not know of any statute that would prohibit for-profit charter companies from providing this service. Cities or counties near the park and ride locations may have local ordinances related to taxi or charter services. Public funds would not be able to be used for a private provider unless they contract with a designated public transit agency to receive funds for service that is open to the public and accessible for persons with disabilities.  The exception to this is Inter City Bus Program funds, which private, for-profit carriers are eligible for if they connect to a nationwide transportation network, have a stop/stops in rural areas (in this case, if they had a stop in Huxley), and do not compete with an existing service.


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