These two bridges cross the Oakland estuary, connecting Alameda Island with the city of Oakland.
Excerpted from the County Public Works website:
"The present structure was constructed by the U.S. Army Corp of Engineers and opened to the public on December 12, 1973 and received awards from the Steel Industry for engineering and design excellence. The bridge was turned over to the County in 1975 and was named Miller-Sweeney.
Miller-Sweeney Bridge shall open on signal; except that, from 8:00 a.m. to 9:00 a.m. and 4:30 p.m. to 6:30 p.m. Monday through Friday except federal holidays, the draws need not be open for the passage of vessels. However, the draws shall open for the above closed periods for vessels which must, for reasons of safety, move on a tide or slack water, if at least two hours notice is given. The draws shall open as soon as possible for commercial vessels engaged in rescue or emergency salvage operations.
Vessel and Vehicle Traffic
1,588 Opening per year
1,750 Total Vessels
615 Barges
Total Vehicle Traffic per day 15,300
WORKINGS OF THE BRIDGE
Miller-Sweeney is a single leaf bascule bridge and .... our fastest bridge; after securing the bridge for an opening it takes 66 seconds to raise the bridge to a height of 79 degrees, a full opening. Power is supplied by two 75 hp electric motors. These motors operate in tandem for a normal opening. However, each motor can operate the bridge on its own if necessary. "
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The railroad bridge is maintained in the raised position at a height of 65 feet, which is considered passable by vessels which might use this portion of the estuary.
"The Fruitvale Ave Railroad Bridge opened for service in June 1951. The Bridge cost $946,757.00 to build. The prime contractors were Ben C. Gerwick, Southern Pacific, Judson-Pacific, Murphy Construction, and Independent Construction Company. The bridge is a vertical lift design so it has two support towers for the counterweights, machinery rooms, and span. The towers are 185 Feet tall with the machinery rooms at the top."
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The railroad is not using this track as of 2009 and a section of track has been removed on the Alameda side of the bridge; however, the railroad still owns the right of way and it is possible that changing conditions would require this bridge to return to duty.