Reconstruction plans for a major Indianapolis intersection are moving ahead

Plans to rebuild a downtown Indianapolis intersection that serves about 214,000 vehicles every day are moving forward.

The North Split that connects I-70 and I-65 is the second-most heavily traveled interchange — and the most dangerous — in Indiana, according to a newly released document from the Indiana Department of Transportation.

Crash rates in the interchange are more than twice as high as other Indiana urban interstates, the July document says, and not only because of the high traffic volume. The interchange's design, including the "abrupt curve" from the south leg to the east leg, is also factor.

INDOT has been planning the project for more than two years.

In 2018, the department received pushback from a group of neighborhoods, businesses, civic organizations and private citizens who thought the plan would harm the city's future.

The Rethink 65/70 coalition asked INDOT to radically rethink how the interstates moved through downtown, even suggesting a depressed interstate covered in greenery. The coalition and other opponents worried the initial design would add to problems created when interstate systems divided downtown and surrounded historic neighborhoods.

Work on the $240 million project could begin this winter and last two years, according to the assessment document.

While a final plan has not yet been approved, INDOT spokesperson Mallory Duncan said major changes to the current preferred option are not expected. Duncan said the department will need to work with the Federal Highway Administration before moving to final design and construction.

The North Split contains 3.1 miles of roadway and spans from the I-70 Valley Avenue bridge to the east, the I-65/I-70 and Washington Street interchange to the south, and the I-65 Alabama Street bridge to the west. INDOT says it wants to rebuild the interchange because the infrastructure is deteriorating and the design contributes to traffic and safety concerns.

Most of the infrastructure is more than 50 years old, and 32 bridges need to be fixed or replaced.

"In addition to its poor physical condition, the interchange configuration is inefficient and poorly suited for the volumes of traffic it is serving," the INDOT document says.

Crashes with no injuries were 2.3 times more common than other urban interstates in Indiana. Crashes with injuries were 2.8 times more common. INDOT says these higher rates are not just because of the high traffic volumes.

Crashes are often caused by merges, weaves and lane changes that drivers must make over short distances to enter the interstate or reach an exit ramp.

In addition to replacing existing bridges and repaving the roadways, the reconstruction project would rebuild ramps and reconfigure the interchange to improve the flow of traffic.

Construction could begin this winter and take two years. INDOT's goal is to complete the project by the end of 2022.

Interstate 465 would be used as a detour for through traffic on I-65 and I-70.

All downtown exits and entrances outside of the project would stay open during construction, INDOT said. 

Detours would be set to ensure drivers could continue eastbound and westbound from I-65 to I-70, though weekend or night closures may occur.

The project has faced some opposition. The Rethink 65/70 coalition called on INDOT to reconsider its initial plans and asked for no lane expansion, no above-grade walls, and better connectivity between the downtown highways, among other items.

INDOT says it took the feedback into consideration.

"INDOT has made efforts throughout the North Split project development process to avoid and minimize impacts of the project on adjacent neighborhoods," the document said.

To address noise concerns, INDOT said it would use pavement that does not include joints, which are the cause of rhythmic sounds on the current roadway. The department said it would also use a new grooving technology to reduce tire noise.

The department says the current plan results in a more compact interchange, moving some interchange ramps farther away from residential areas.

"Generally speaking, the Rethink Coalition is pleased with the results it fought for, and appreciates INDOT substantially modifying its original plans, in the North Split project," Paul Knapp, a member of the Rethink leadership group, told IndyStar in an email.

"Specifically, the major changes the Rethink Coalition and others fought for and which made their way into the final plans include: no new through lanes, dramatically reducing the number and height of retaining walls, dramatically reducing the interchange footprint, keeping Vermont Street open to vehicle traffic under the interstate, improving underpass designs, and planting an urban forest within the open spaces of the interchange," Knapp wrote.

Knapp said the group is disappointed it couldn't persuade INDOT to make more fundamental changes to the design of the interchange. He said the coalition believes it learned of INDOT's plans too late in the process.

The coalition is still advocating for improvements for the Martindale-Brightwood neighborhoods and is working with the Indy Chamber to do design studies for future projects downtown.