Of the 7,800 bridges across the state of Washington, 366 of them have been deemed "structurally deficient" by the U.S. Department of Transportation's Bridge Inventory Database.
Structurally deficient is defined as a bridge that has one or more structural defects that require attention. The USDOT also issues ratings for the condition of each bridge. The scores - entitled sufficiency ratings - range from 1 to 100, with 1 being the worst. The ratings are based on the condition of the bridge's deck, superstructure (structural elements that support the deck) and substructure. The substructure is the bridge's foundation that supports the superstructure and includes abutments and piers.
You can see the list of the worst rated bridges here. Please note, this database is maintained by the US Department of Transportation and some bridges on the list may have already been replaced.
In Washington, the lowest rating currently is a two. There are four bridges with that suffiency rating. Here are the locations:
- Puyallup, on SR 167
- Skykomish, on County Rd. 41640
- Seattle, South Park Bridge (currently being replaced)
- Union Gap (near Yakima), on S. 12th Ave. Bridge
The next lowest rating on bridges in the state is a four. Seven bridges carry a suffiency rating of four. Here are the locations:
- Grays Harbor, on Mattson Rd.
- Spokane, on Little Spokane Rd.
- Mason County, on County Rd. 41640
- Kent, the Alvord T (to be demolished in June)
- Seattle, on Airport Way S.
- Plain (near Leavenworth), on Chiwawa River Rd.
- Lewis County, on SR 508
In King County, 38 of the 180 bridges in the area are listed as structurally deficient. Eleven of those feature a steel truss design, including the 99-year-old Alvord T Bridge in Kent that will be torn down next month due to safety concerns. The steel truss design is similar to the Skagit River Bridge that collapsed Thursday.
King County Executive Dow Constantine has asked his road and bridge specialists to investigate each of those eleven steel truss bridges to see what can be done, if anything, to make them safer. Initial ideas include adding signage to better alert the public to height and weight restrictions.
"I'm asking our roads folks to report back to me what can be done to make sure we don't have this type of incident," said Constantine. "This is a design issue and it involved a truck that was clearly too big or in the wrong place. How can we keep oversized vehicles or those that are driving in the wrong lane from damaging these structures?"
Constantine has asked for the reports to be completed by next week.
The King County Roads Services Director, Brenda Bauer said financial resources for road and bridge work has dwindled by about a third since 2010 due to the recession. The funding dropped from $135 million per year to $85 million, which means instead of replacing several bridges a year, a new bridge is not scheduleld to be constructed until 2017 in the county.
"(That) just means that we are going to be closing infrastructure instead of replacing it and we'll be behind in our capital investments in roads and bridges," said Bauer.
Bauer added that the public should not be worried about crossing bridges in King County.
"King County bridges are safe. We're not concerned about people using those bridges everyday. We will close the bridges before they are unsafe," said Bauer.
Constantine said the collapse of the Skagit River Bridge should be a wake up call for the entire state, which is in need of funding to replace and maintain infrastructure.
"(The collapse) illustrates now for our whole community that our system is vulnerable across this state and we need to continually reinvest in and renew the infrastructure if we're going to have a strong economy and safe travels," said Constantine.