-Ross Island   ROSS ISLAND BRIDGE BRIDGE FACTS Type: Cantilever Truss At mile marker: 14.0 Overall length: 3,729' Owner: State of Oregon           The Ross Island Bridge was opened in 1926 to accommodate Portland's burgeoning private automobile traffic. It was designed by Gustav Lindenthal of New York City and, like his Queensboro Bridge across the East River in NYC, it is a semi-continuous cantilever structure. There are steel truss anchor arms connected to points on shore, but there is no central suspended span connecting them. Instead those anchor arms support truss panels which project out (cantilever) from piers to the center.         While it's not an arch bridge as many may think, it is an aquaduct which many don't notice. Two 24-inch mains on the bridge convey millions of gallons of water from the Bull Run Reservoir east of town to Portland's west side.   Choose a bridge to view! Jump to a bridge here Burnside (*) Broadway (*) Fremont Hawthorne (*) Marquam Morrison (*) Ross Island St John's Sellwood Steel (*) - - See All Bridges - - (*) indicates a Legacy Project Bridge Home : Bridges :Legacy Project : Permitting Process : News : Shop : Contact : Committee : About Us / Join ©2000-2004 . All rights reserved