It's a steel truss bridge, meaning it has a boxy steel frame.
The lighthouse stands on a rugged tall cliff, connected to the mainland by a narrow steel suspension bridge.
The steel and concrete bridge was opened in 1875 and was last used in 1968.
The two local authorities have agreed to share the costs of building and maintaining the steel-beamed bridge and its reinforced concrete deck.
Travis Phelps, spokesman for the Washington State Department of Transportation, said a flatbed truck with an oversize load hit the upper part of the steel-lattice bridge.
WSJ: Bridge Collapse in Washington State Sends People, Vehicles Into River
Eventually the train tracks crossed over Lovell Road, and we got off them there while the road took us across the river on a steel and concrete bridge that was falling to pieces now.
It was a steel and concrete arch bridge like many in the country that are carrying more and more traffic every day.
Dorgan also cited an in-depth study of the bridge's fatigue potential conducted from 2004 to 2007 that recommended two alternatives for the bridge's future -- to add steel plates to reinforce critical parts of the bridge or to conduct thorough inspections of the wells inside the box to determine whether there were cracks.
Later, inspectors found corrosion of steel around joints in the bridge and fatigue cracks in the approach spans.
The projected losses stem principally from the dispute with the steel sub-contractor Cleveland Bridge (CBUK), which left the site last year.
"This is a really significant event and we need to learn from it, not just in Washington but around the country, " Hersman said after taking a boat ride on the Skagit River below the dramatic scene where a truck bumped against the steel framework, collapsing the bridge and sending two vehicles and three people falling into the chilly water.
The new bridge is an innovative spiral structure formed from tubular steel.
The temporary solution developed by the state's Department of Transportation includes using steel girders at the site of the collapse while a permanent bridge is built.
How smart is Dagny and Ellis for not testing the steel themselves but they bravely ride a high speed train over a bridge made of it?
Investigators with the National Transportation Safety Board said Wednesday they had found design flaws in the bridge's gusset plates, which helped tie the steel beams together.
Daniel Garber employs broken Impressionist brushstrokes in "The Bridge at New Hope" (1952), its steel-truss span evoking the serene industrial views of Charles Sheeler and the American Precisionists.
WSJ: Nature in America | A Landscape in Evolution | By Barrymore Laurence Scherer
In Washington state this past week, a bridge collapsed when a truck driver's load bumped against the steel framework.
While Bill Gates and Warren Buffett--numbers one and two on last year's Forbes Billionaires list-- engage in a genteel game of bridge, Lakshmi Mittal is ripping apart the world's steel industry and reshaping it to his liking.
The bridge was rebuilt in 1985 along the same lines, but made of steel rather than cast iron.
The work involves screening off sections of the bridge before old paintwork is removed and any repairs carried out on the bare steel.
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