520 Floating Bridge on Lake Washington

Lake Washington is a very deep lake that made conventional bridge construction difficult.  To allow a traffic to cross the lake, a floating bridge was constructed.  This bridge’s draft was approximately 2.5 meters below the water surface.  The bridge effectively stops floating objects and wind generated wave action from passing under the bridge.  To demonstrate this, our EFDC+ model of Lake Washington was modified to add the floating bridge blockage and Lagrangian particle tracking was conducted.  Four particle groups were released, at two depths North and South of the bridge.  The two release depths of 1.5 meters and 4.5 meters were set to be blocked by the bridge or flow under the bridge, respectively.