Know your Sling
The bridge: one of many Double Bascule drawbridges within the NYC area.
Space under the roadway.
Interior space.
Interior motor room, exposed. This room is normally covered by the roadway and inside of the base of the bridge.
Control Tower, Empty and In Rehab, just like your mom.
Road Closed. No traffic worries here...
The NYC area is geographically home to many, many waterways,
both large and small. Some of the smallest waterways and swamps were filled
in and / or covered over during the development of the city, and all of the
major waterways were (and to some degree still are) home to industrial complexes
along their shores. Where the roads and railroads met these waterways, often
the answer to allowing both auto and nautical traffic was to build drawbridges.
Drawbridges come in several varieties, the main three being bascules, Lifts
and Swings. A Bascule lifts upward at one end and the roadway becomes vertical,
perpendicular to the waterway. This allows the maximum overhead clearance
for the tallest possible boats. Swing Bridges rotate on their center, allowing
for 2 channels of water to pass when in the 'open' position, and Lift bridges
lift vertically over the waterway. NYC is also home to at least one 'slide'
bridge, which strangely enough slides on tracks on a diagonal angle into a
space onto the shoreline.
There are, of course, variations on all of the above. This bridge is exactly that: a double bascule - whereby two spans lift vertically from both shorelines. (This particular bridge is a rather small example of this type of structure. There is a similar bridge nearby supporting a much larger roadway that is actually a quadruple bascule. Watching it open is plenty interesting, as none of the 4 movable spans opens in exact sync.) Each base has it's own motor room build in under the base of the bridge. The photos to the left provide a rare glimpse into the interior of the base of this type of bridge.
There are, of course, variations on all of the above. This bridge is exactly that: a double bascule - whereby two spans lift vertically from both shorelines. (This particular bridge is a rather small example of this type of structure. There is a similar bridge nearby supporting a much larger roadway that is actually a quadruple bascule. Watching it open is plenty interesting, as none of the 4 movable spans opens in exact sync.) Each base has it's own motor room build in under the base of the bridge. The photos to the left provide a rare glimpse into the interior of the base of this type of bridge.
