INDOT confident Section 4 of I-69 will open by the end of 2015

That might be hard to believe for anyone who has driven through what will become the Ind. 37 and I-69 interchange in southern Monroe County. There, I-69 is still a dirt path, but go to the other end of the 27-mile section near Naval Support Activity Crane, and you'll find about 4 1/2 miles of smooth concrete. It ends in dirt for now, but that won't last long.

"Earth work and bridges take up the vast majority of time," Wingfield said. "In the next month or so, all embankment work will be done, and all the contractors will be into paving."

Earth work and unfavorable weather conditions are what the department of transportation blamed for pushing the project's opening date back a year. When Sections 1 through 3 were finished at the end of 2012, the department of transportation still expected Section 4 to be open to traffic by the end of 2014. Mother Nature had other plans, though.

To ensure the safety of drivers, inclines and declines on interstates can't be too steep. To meet those requirements, contractors had to cut hills and fill valleys.

When a valley is filled, only 8 inches of loose lifts, as they're called, can be deposited at a time. Rollers must then compact the dirt down to 6 inches with rollers. A department of transportation official must then test the stability of the soil before another 8 inches can be put down. Crews can generally put down two loose lifts a day, if the soil is dry.