Opened in 1910 and spanning the Willamette River in Portland, OR, the Hawthorne Bridge is the oldest vertical lift bridge still operating today in the United States. Designed by Waddell & Harrington, which later became Hardesty & Hanover (H&H), it is one of several H&H legacy projects that is still standing the test of time more than 100 years after its original construction. J.A.L. Waddell, considered the inventor of the modern-day vertical lift bridge, was also responsible for another iconic Portland vertical lift bridge, Steel Bridge, which opened two years later in 1912.
The Hawthorne Bridge is a 1,382-foot-long Parker truss bridge with five fixed spans and one 244-foot-long lift span. Its towers rise 165 feet above the bridge deck and support counterweights of approximately 450 tons each. When open, the lift span allows for a vertical clearance of 110 feet for vessel navigation underneath. Portland’s busiest bicycle and transit bridge carries an impressive mix of numerous pedestrians, 8,000 bicycles, 800 TriMet buses, and 30,000 cars and trucks daily. The lift span is opened as many as 200 times per month.
In the late 1990s, H&H was retained by Multnomah County to investigate and identify issues related to the bridge’s rehabilitation. H&H inspected the bridge and developed a bearing realignment plan that could be completed without taking the lift span out of service. H&H also developed an inspection program for the County to continue to obtain critical information on the shaft until the time comes when a more substantial rehabilitation would become necessary.
The Hawthorne Vertical Lift Bridge profile is part of H&H’s on-going celebration of our heritage as we approach our 135th Anniversary.