Vertical Lift Bridges
Those bridges which seem lost in time. These massive pieces of construction and marvelous architectural design simply awe.
When paddling our rivers, I pause to admire our magnificent bridges. Among my favorites are those designed to rise and make room for awaiting boaters, whether it is the owner of a 30’ cruiser with its too-tall bridge, or captain of the 1,000-foot ocean-like freighter. My two favorite vertical lift bridges, and likely the most photographed, are Duluth’s Aerial Lift Bridge connecting Lake Superior and Superior Bay, and the Stillwater Bridge on the scenic St. Croix. These bridges seem almost lost in time, monuments whose real purpose have been lost like old neighborhood fire-alarm boxes or phone booths that use to adorn what seemed like every street corner. Of course, I love them. They are visually striking, but unwieldy. I have since learned, vertical lift bridges were favored in the early 1900s, unlike bascule bridges, these require counterweights only as heavy as the bridge span itself. This means that the spans can be heavier, and thus well suited for the demand and pounding of heavy freight train traffic. Although over the years a few have been abandoned, these massive pieces of construction and marvelous architecture remain surprisingly active and still fill their original grand purpose. |