A Des Moines Asphalt and Paving Company/Nuckolls Concrete Services, Inc. joint venture is at work on the Iowa Department of Transportation's largest-ever contract, a $43.8-million job which includes 15 separate projects that are part of the $429-million, multi-year reconstruction of Interstate 235 through Des Moines.

Major parts of the work between 73rd Street in West Des Moines and Cottage Grove in Des Moines are Hot Mix Asphalt and Portland Cement Concrete paving and the rehabilitation or replacement of eight bridges.

"With so much equipment and everyone trying to get their work done in the same area, the biggest challenge on the project is coordinating and staging," said Project Manager Liz Baloun, of Des Moines Asphalt and Paving. "The major subs, Reilly Construction Company and the three bridge contractors — United Contractors, Cramer & Associates and Jensen Construction Company — are key to the success of the project and they are all performing very well. Those contractors and the others have been doing a great job getting the work done when it has to be done."

Work began in March with the focus on getting the interstate back to its final lane configurations by November 23 to earn a $1-million bonus.

Eastbound traffic on the interstate from 17th Street to Cottage Grove was switched to two lanes in each direction head-to-head on the existing westbound roadway while the eastbound roadway was reconstructed.

Des Moines Asphalt and Paving crews completed their intermediate eastbound paving by late-July then switched traffic to two lanes in each direction head-to-head on the new eastbound roadway to begin reconstruction on the westbound roadway.

At the same time, the bridge contractors had completed their modifications to the 8th Street, 73rd Street, Walnut Creek and Cummins Parkway bridges, and completed the eastbound 35th and 28th Street bridges. "After we switched traffic, we started our 35th and 28th Street mainline bridges westbound along with pavement removal and reconstruction on westbound 235," Baloun said. "In order to earn our bonus, we have to have traffic to its normal configuration — out of head-to-head traffic — so we have to have all our bridges reconstructed and all our intermediate paving in by November 23."

Traffic will run on the intermediate course through the winter and the surface course will be laid next spring. "In order to prevent leaving grind marks in the surface course from paint removal due to switching traffic for staging, we have to have traffic in the final lane configuration before we start our surface course," said Baloun. "Waiting until spring to do the surface course will make it a much better roadway."

Looking ahead at the first week of August, Baloun was confident that the joint venture team and its subcontractors would complete their work for the bonus.

"We are a couple weeks behind due to plan revisions and extra work orders," she said. "However, with key subcontractors on an accelerated schedule, working six to seven days a week, I am confident that we will make our completion date to earn our bonus."