Movable Bridges There are three basic types of movable railroad bridges: vertical lift, swing, and bascule. A trip across the middle of Georgia from west to east provides examples of each. Vertical lift bridges use a movable span raised by tower-mounted motors. Huge counterweights attached to cables assist the motors in lifting the span. The bridge shown above crosses the Chattahoochee River at Omaha, about 30 miles south of Columbus. Swing bridges move horizontally rather than vertically. Pivoting atop a pier, the span can "swing" away from the navigation channel, allowing a boat to pass with no vertical obstruction. This bridge is over the Ocmulgee River at Lumber City, between Macon and Brunswick. A bascule bridge moves vertically by rotating upward from one pier. Like the vertical lift bridge, a bascule bridge has counterweights that help motors move the multi-ton span. The bridge above, over the Savannah River in downtown Augusta, is a rolling lift bascule. Its counterweights can be seen in the top right of the photo. The days when these particular movable bridges actually moved may be coming to an end. Today the Omaha bridge stays in the up position because the railroad it carried has been abandoned. The bridges at Lumber City and Augusta still carry trains but barge and steamboat traffic has vanished so there is seldom a reason for these bridges to move. RailGa.com. Georgia's Railroad History & Heritage. © Steve Storey Railroad History | The Depot List | Locomotives On Display | Odds & Ends | Sources & References | Home