A bridge inspector for the Kansas Department of Transportation has resigned following the fall of a 60-foot section of concrete barrier wall from an interstate viaduct in Topeka.
KDOT reports that the north barrier wall over I-70 west fell June 11 due to deterioration of steel that connects the wall to the viaduct, an expanded bridge joint and high temperatures. It fell into an empty parking lot, with no injuries reported.
During an internal investigation of the incident, KDOT found that an inspection done May 23 of the Polk-Quincy Viaduct did not follow proper procedures.
“The inspector saw warning signs that the bridge joint was expanding, but failed to notify KDOT’s bridge inspection leader, which is required per the protocol,” KDOT says. “The bridge inspector responsible for the error has resigned.”
The concrete barrier broke adjacent to the expansion joint, the agency says.
KDOT has also hired a national bridge expert to help with its investigation into the fallen wall section. The expert will review internal processes to make recommendations to the agency.
An external audit of all bridge inspections, including those made by the inspector who reviewed the viaduct, will be conducted, according to KDOT.
“There are 332 bridges across Kansas whose barriers and railings are similarly designed to the Polk-Quincy Viaduct,” the agency says. “KDOT has called for additional inspections of all those bridges. The bridges that span over traffic, approximately 105 of them, will be inspected first.”
Though the viaduct remains open, streets beneath the fallen section have been closed to drivers and pedestrians until the concrete barrier can be removed and replaced. Work on the barrier is expected to begin June 30.
KDOT’s state bridge engineer, senior inspection engineer and a consultant have inspected the fall site multiple times and “have determined the cause to be an issue with the concrete barrier alone. The structure of the viaduct remains sound and open to traffic.”
Daily inspections have occurred since June 13 at the site, KDOT says.
“It’s important to note that concern is with the concrete barrier and not the structure of the I-70 Polk-Quincy Viaduct, which remains open to traffic,” the agency says.
The viaduct was built in the late 1950s and has deteriorated in condition, as well as seen increased traffic. The I-70 Polk-Quincy Project, planned by KDOT and the city of Topeka, will replace the viaduct to improve traffic flow and safety. Property appraisals and right-of-way acquisitions are underway, according to the project’s website. Pavement and deck patching on seven bridges along I-70 in downtown Topeka is also planned for 2022 and 2023.
The 2-mile project is estimated to cost $234 million, with work on the viaduct replacement scheduled for 2025. It will widen I-70 from four to six lanes from MacVicar Avenue to Topeka Boulevard and replace the viaduct and roadway to 4th Street.