Delaware officials should have closed a damaged interstate bridge sooner and missed opportunities by not having qualified personnel respond quickly to tips about the bridge's deterioration, the state's transportation secretary said Thursday.
An internal report released Thursday documents a series of missteps leading up to the June 2 emergency closure of the Interstate 495 bridge in Wilmington.
The report says Department of Transportation officials did not respond appropriately to two separate 911 calls, one in April and the other in May, suggesting something was wrong with the bridge. They also took several days to act after receiving an engineer's warning in May that columns of the 495 bridge over the Christina River appeared to be tilting.
"There are three missed opportunities ... to have closed the bridge sooner," said transportation secretary Shailen Bhatt. "We obviously should have reacted quicker."
Bhatt said his department already has implemented new procedures to ensure a timely and appropriate response to problems both with bridges and other infrastructure, including overhead signs, dams or dikes, and lighting structures. In the case of bridge problems, a maintenance supervisor and a qualified inspector or engineer will respond, he said.
"It's not that we got these reports and ignored them," Bhatt said. "It's that we got these reports and we did not have the right people who were going out to put eyes on the bridge."
But the Department of Transportation's own investigation shows that high-ranking officials within the agency's bridge section took a lackadaisical approach to warnings about the bridge, which typically carries about 90,000 vehicles a day on an 11-mile bypass around Wilmington.
On May 29, a geotechnical engineer working in the area on an unrelated project alerted officials that the bridge columns appeared to be tilting. In response, DOT bridge design engineer Jason Hastings sent an email to fellow bridge engineer Jason Arndt saying "it would be worthwhile for us to have a team stop by the bridge tomorrow to check it out."
In response, Arndt noted that he and associate bridge inspection engineer Matt Mortensen would be in the area "sometime within the next week" and would take a look then.
The following day, DOT officials received their second 911 call about the bridge, from a motorist who reported that the center span appeared to have sunk in the previous couple of days.
The traffic management control dispatcher who took the call did not alert bridge officials, but instead contacted a motorist-assistance patrol driver and asked him to investigate. The driver reported that he didn't find anything wrong, the report said.
"That's a miss by us," Bhatt said. "I don't know why he didn't see it."
Arndt and Mortensen did not go to the bridge until the following Monday. A few hours after their arrival, a DOT equipment operator and a DOT street sweeper reportedly separately to supervisors that there was a problem with the barrier wall on the bridge. The bridge was closed later that day.
Bhatt would not say whether any DOT officials will face disciplinary action, but he noted that a human resources investigation was underway.
"If there are actions that warrant discipline, we will absolutely take the appropriate action. ... Every single employee's involvement in this is being evaluated," he said.
The Federal Highway Administration, which has approved emergency relief funds to repair the bridge, has said the bridge's design and construction met applicable standards. The agency also said it appears the bridge has been properly maintained and inspected.
Bhatt said Thursday that his agency has confirmed officials' initial suspicions that a large dirt mound dumped next to the bridge, apparently without the knowledge or consent of state officials, caused soft underground soils to move, damaging the concrete footers and underground pilings that support the bridge columns. They estimate the mound weighed about 50,000 tons.
"It is clear the dirt has caused the lateral displacement," said Bhatt, adding that his agency has hired legal experts to investigate to potential third-party liability claims for bridge repair costs.