A submersible bridge is a type of
movable bridge that lowers the bridge deck below the water level to permit waterborne traffic to use the waterway. This differs from a
lift bridge
A vertical-lift bridge or just lift bridge is a type of movable bridge in which a span rises vertically while remaining parallel with the deck.
The vertical lift offers several benefits over other movable bridges such as the bascule and swi ...
or
table bridge, which operate by raising the roadway. Two submersible bridges exist across the
Corinth Canal in
Greece
Greece, officially the Hellenic Republic, is a country in Southeast Europe. Located on the southern tip of the Balkan peninsula, it shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, and Turkey to th ...
, one at each end, in
Isthmia and
Corinth
Corinth ( ; , ) is a municipality in Corinthia in Greece. The successor to the ancient Corinth, ancient city of Corinth, it is a former municipality in Corinthia, Peloponnese (region), Peloponnese, which is located in south-central Greece. Sin ...
.
They lower the centre span to 8 metres below water level when they give way to vessels crossing the channel.
The submersible bridge's primary advantage over the similar lift bridge is that there is no structure above the shipping channel and thus no height limitation on ship traffic. This is particularly important for sailing vessels. Additionally, the lack of an above-deck structure is considered aesthetically pleasing, a similarity shared with the Chicago-style
bascule bridge
A bascule bridge (also referred to as a drawbridge or a lifting bridge) is a moveable bridge with a counterweight that continuously balances a span, or leaf, throughout its upward swing to provide clearance for boat traffic. It may be single- o ...
and the
table bridge. However, the presence of the submerged bridge structure limits the
draft
Draft, the draft, or draught may refer to:
Watercraft dimensions
* Draft (hull), the distance from waterline to keel of a vessel
* Draft (sail), degree of curvature in a sail
* Air draft, distance from waterline to the highest point on a v ...
of vessels in the waterway.
The term ''submersible bridge'' is also sometimes applied to a non-movable bridge that is designed to withstand submersion and high currents when the water level rises. Such a bridge is more properly called a
low water bridge.
See also
*
Low water crossing, a non-moving bridge that is sometimes submerged
*
Moveable bridges for a list of other moveable bridge types
*
Table bridge, a similar bridge that moves upward
*
Underwater bridge, a non-moving military bridge that is always submerged
References
External links
''Popular Science'', November 1943, '' "Ducking Bridge" Lowers Span To Allow Ships To Pass''built in Iraq in 1943 (bottom-right hand side of page)
Video of the operation of a submersible bridge at the entrance of the Corinth Canal
{{DEFAULTSORT:Submersible Bridge
Bridges
Moveable bridges
Bridges by structural type