CORALVILLE — With the Iowa River Landing development in Coralville growing and drawing thousands of visitors to the area, local officials say the time has come for a necessary but costly upgrade to the nearby interstate access.
Coralville officials have been speaking with the Iowa Department of Transportation, and made their case again to the Iowa Transportation Commission this week, to replace Interstate 80’s First Avenue interchange, exit 242, to handle a higher volume of traffic.
“Based on MPOJC traffic studies, it is nearing the end of its life as far as being able to convey traffic safely, so it’s getting close to being needed to be upgraded,” Coralville City Engineer Dan Holderness said to the commission this week.
MPOJC, or Metropolitan Planning Organization of Johnson County, is a transportation planning organization for the area.
The estimate to replace the interchange is $19.3 million. Coralville officials hope to get it on the Iowa DOT’s five-year plan, which is updated annually, and get started with construction.
The rural diamond style interchange was built in the 1970s and has served one of Iowa’s fastest growing communities well over the years, Holderness said. But, that intersection now sees around 80,000 cars a day between traffic on First and I-80, he said.
The Iowa River Landing, which the city converted from an industrial park to a retail area along the Iowa River, and which features a University of Iowa outpatient clinic and convention center, is coming together with new buildings still going up.
An intermodal transportation hub that should be complete next summer will serve as a park and ride facility for 275 cars, and University of Iowa Hospitals and Clinics is planning to add more clinic and office space.
Holderness called it an active and growing area that will continue to see increases in local and regional traffic.
“We drove through there, and we felt like every time we blink, there’s a new building going in there,” Commissioner Amy Reasner, of Cedar Rapids, said regarding a previous day’s tour of the area.
Coralville has design concepts for a preferred replacement interchange known as a diverging diamond, or DDI. The interchanges have been used in Europe for decades, but are fairly new to the United States.
“The Diverging Diamond is based on the idea that if you can eliminate the need for left-turn arrows, then signals will have maximum efficiency, fewer conflict points, and be able to serve more traffic with better safety and less congestion,” according to a website called DivergingDiamondInterchange.org.
This would be just one interchange project for the area.
The interchange for Interstate 80 and 380 and Highway 218 is slated to be overhauled beginning in 2018.
The most recent five-year plan calls for a brand new interchange at Forevergreen Road, which is near the Coralville-North Liberty border. That $14.2 million project slated for 2019 will serve the area, which will see two new schools built in coming years.
“We are very pleased and appreciative seeing the Forevergreen Road interchange added to the five-year plan,” North Liberty City Administrator Ryan Heiar said. “We believe this is a necessity for both traffic flow and economic development.”