DOVER, Del. (AP) -- Some bridges in need of repair in Delaware and Maryland could collapse if a single, vital component fails, but transportation officials say motorists in Delaware and Maryland don't need to worry about the safety of the structures in the two states.
A nationwide review by The Associated Press identified almost 7,800 bridges considered both "structurally deficient" and "fracture critical."
Structurally deficient means a bridge is in need of repair or replacement because at least one major element — the deck, superstructure or substructure — is in poor condition. Fracture critical means a bridge doesn't have redundant structural protections and is at risk of collapse if a single, vital component fails.
The lists fluctuate frequently, and there is considerable lag time between when state transportation officials report data to the federal government and when updates are made to the federal National Bridge Inventory. Because the federal inventory relies on information from state departments of transportation, state officials have the latest records.
The AP review found seven bridges in Delaware and 28 in Maryland that fall in both red-flag categories, but officials in the two states say at least three of those bridges are no longer considered structurally deficient.
Officials in Delaware and Maryland also note that repairs are underway or planned for other bridges, and that weight restrictions are placed on some bridges in need of repair to ensure public safety.
"If a bridge posed a risk to public safety, then the bridge would either be load-posted accordingly or be recommended for closure," DelDOT spokesman Geoff Sundstrom said.
Spokesman John Sales of the Maryland Transportation Authority said the agency, which maintains all toll bridges in Maryland and all bridges along Interstate 95 between Baltimore and the Delaware state line, would never allow an unsafe bridge to remain open to traffic. The transportation authority is responsible for 319 bridges, as well as 206 smaller spans measuring less than 20 feet.
Of the 28 Maryland bridges identified in the AP review, most are the responsibility of local governments, with two others maintained by the transportation authority and one by the Maryland State Highway Administration.
But officials said the two transportation authority bridges — the Patapsco Flats and K Truss bridges on Interstate 895 on the southern outskirts of Baltimore — were both inspected this past spring, and weren't considered structurally deficient based on the most recent submission to federal highway administrators. The transportation authority said its only bridge currently considered structurally deficient is the Canton Viaduct bridge on I-895 on the northern end of the Baltimore Harbor Tunnel, and that plans are underway to replace the bridge, which is not fracture critical.
Meanwhile, the Maryland State Highway Administration, which oversees almost 2,600 bridges and overpasses, said only one of its bridges, the U.S. 1 bridge spanning a CSX railroad southwest of Baltimore, is both structurally deficient and fracture critical. SHA officials noted that the only reason the bridge is considered structurally deficient is because its concrete deck, the surface on which vehicles travel, needs repair.
SHA spokesman David Buck said the U.S. 1 bridge — which has been listed as structurally deficient since 1996 because of its deck condition — was inspected July 13, and that design and engineering work on repairing the deck are underway.
Of the 25 locally managed bridges in Maryland identified by the AP as both structurally deficient and fracture critical, Buck said the SHA has reviewed work plans for seven of them, meaning the local jurisdictions want to use federal funds and have submitted plans to SHA for review. But SHA officials said there's no way for them to know when the work might be done because the local jurisdictions control construction schedules.
Buck said that of the handful of SHA bridges listed as both structurally deficient and fracture critical in the past five years, all were considered structurally deficient only because of the condition of the deck, or riding surface.
He also noted that the number of SHA bridges that are structurally deficient, regardless of whether they are fracture critical, has been cut almost in half over the past decade, from 156 in 2001 to 87 this year.
The number of structurally deficient bridges in Maryland not maintained by the SHA has fallen from 292 in 1999 to 240 in 2012, and the number of weight-posted county bridges has been reduced from 835 in 1998 to 506 in 2012, Buck added.
Among the 240 structurally deficient local bridges, 32 are in the city of Baltimore and 29 in Baltimore County. Prince George's County has the third-highest total, 19.
Meanwhile, in Delaware, officials say work is underway or planned on six structurally deficient and fracture critical bridges.
Special inspections were scheduled to begin this month on two of the bridges, the South Walnut Street bridge over the Christina River in Wilmington, and the James Street Bridge over the Christina River in Newport.
Work on the Walnut Street bridge and the Fourth Street bridge over the Christina River in Wilmington should be completed by the end of the year, according to DelDOT. Upon completion of the construction, load restrictions of 18 tons for those bridges will be removed and they will no longer be structurally deficient, officials said. The James Street Bridge is scheduled to be replaced, with construction expected to start in fiscal 2015.
DelDOT officials also said work is currently being done on three other structurally deficient, fracture critical bridges in Newport: the Route 141 bridge over the Christina River and Amtrak rail lines, the Route 4 bridge over Ayers Street to southbound Route 141, and the Route 141 northbound ramp over Ayers Street to Route 4.
A seventh bridge identified in the AP review, a private/park road over Red Clay Creek in Yorklyn, was removed from the structurally deficient list after repairs to its timber deck last year, according to DelDOT.