The Hawthorne Bridge is a six span, 1382 ft long, truss bridge with a 244 ft long lift span. It has 49 ft of vertical clearance when it's closed and 159 ft when it's open. It replaced the second Madison Bridge, which was built in 1900 and destroyed by fire in 1902 (the bridge connects Madison Street to Hawthorne Blvd. in Portland). The 440 US ton counterweights are suspended from 165 ft tall towers. It was designed by John Waddell who invented the lift bridge (see comments) and designed the nearby Steel Bridge (see the September 12th posting). However, unlike the Steel Bridge, it has only a single deck with two lanes inside the truss and two lanes and wide bicycle lanes/sidewalks outside the truss (widened and restored in 1999). The bridge cost $511,000 and it's estimated to have a replacement cost of about $190 million.
Portland's Bridges: Hawthorne Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.
Vertical lift bridges weren't invented by Waddell. Squire Whipple built several before him, and both are pre-dated by some 1868 lift bridges built in Paris.
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