Photo provided by Scott Keen Supports are shown under the Gateway Arch Bridge on Columbus’ west side as the Indiana Department of Transportation continues work to add additional hangar support to the bridge this winter.
The Indiana Department of Transportation is installing permanent supplemental hanger systems on the I-65 Gateway Arch Bridge over State Road 46 as a precautionary measure after some corrosion was found during recent inspections.
Motorists who travel through the major intersection on Columbus’ west side have noticed supports under the bridge and new traffic patterns to the entry and exit ramps on State Road 46 since the work began.
Permanent supplemental hanger systems will be put in place early this year, said Natalie Garrett, strategic communications director at INDOT. After that work is completed, temporary structures will be removed and the interchange operations will be restored back to its original configuration either late this winter or in early spring, she said.
“This work is being done as a precautionary measure due to corrosion found during recent cable inspections,” Garrett said. “The hangers will provide additional support for the I-65 bridge over State Road 46.”
An overweight truck restriction of 80,000 pounds remains in place for the bridge, and truck drivers are warned on I-65 by signs that they must exit before crossing the bridge as the work continues.
Oversize and overweight vehicles in the southbound lanes are instructed to exit I-65 and follow Jonathan Moore Pike east to State Road 11. Trucks can follow State Road 11 south before turning west on County Road 450S, which takes them back to the interstate.
For trucks getting off the interstate from the northbound lanes, Garrett recommends taking State Road 46 (Second and State streets) through Columbus. Trucks can stay on the highway before turning left at the U.S. 31 intersection, which will take trucks back to the I-65 on ramp in Taylorsville.
INDOT worked on the 1995 project when construction began on what was named the Columbus Front Door Project, with the centerpiece of the project being the unique Gateway Arch bridge over State Road 46, which is known as Jonathan Moore Pike in Columbus. The project included a $23 million investment in the new interstate interchange at the state highway.
The 292-foot long Gateway Arch Bridge was publicly touted as a federal demonstration and signature-type structure designed to reflect the uniqueness of the community to visitors. The bridge took 16 months to complete, replacing an existing four-span conventional steel girder bridge.
The current work to add a supplemental hanger system began about six weeks ago, when overnight lane closures went into effect at the same interchange shortly after Thanksgiving. In early December, there were daytime lane and ramp restrictions, as well as posted overweight truck restriction.
Garrett said with the temporary supports and weight limits in place, there is no danger for vehicles crossing the bridge on I-65 or traveling through the intersection underneath the structure as the work continues.
The bridge receives routine yearly inspections by state officials, with traffic lanes being closed while the evaluations are completed.
One of the reasons that there is not concern about the bridge is that it is not in a coastal environment, where bridges suffer corrosion-induced damage from sea salt and humidity. Bridges in south central Indiana can be weakened by ice-melting salt, fatigue stress corrosion and damage from accidents, but usually to a lesser degree, said C. Michael Walton, a civil engineering professor who serves on the executive committee for the Transportation Research Board at the National Academy of Sciences.
However, the main reason for the work is that I-65 has seen exponential growth in traffic volume over the past few years, with nearly 40% of that traffic being freight haulers, according to the American Association of State Highway and Transportation officials.
While the truck weight limit was at one time 50,000 pounds, it’s at 80,000 pounds on most U.S. highways – with some states allowing even heavier vehicles, the association says.
“Between 20 and 30% (of trucks) are overloaded on our highway system in general, and 10 percent of those are more than double the legal load,” Walton said. “They’ve (the bridges) reached their design life much earlier because of the increased traffic and loads.”
The Gateway Arch Bridge was among the major road improvements from downtown to the west side, which has included the 1999 opening of the Robert N. Stewart Bridge and the completion of the railroad overpass project.
Columbus and its partners had a ribbon cutting ceremony Sept. 30, 2020 to officially open a new $35 million overpass project at State Road 46 and State Road 11.
The Front Door Project in its entirety had a price tag of $48 million, according to project records.
