Steamboat Slough Bridge doesn't actually cross the Sacramento River. It carries State Route 160 traffic over Steamboat Slough on the west side of the river. It's a 68.9 m long bridge that was built in 1924.
All of these bridges have height restrictions due to the huge, concrete counterweights (and low cross-beams). The bridges are almost identical with short spans to support the counterweights and long through truss movable spans. They just have different approach spans when a longer bridge is needed.
Movable Bridges - Steamboat Slough Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.