bridges, night passages, and other tricky navigation situations 121
Pier. Support pillars or stanchions between the abutments, which are made of steel,
stone, concrete, or wood. Vessels pass between the piers marked for safe passage.
Fenders. Protective walls placed on each side of the piers of passage. Th ese walls
consist of wood or composite plastic. Th ey protect the piers if a vessel loses
control during its passage.
Dolphins. A cluster of pilings lashed together. Dolphins serve the same
purpose as fenders, protecting the piers if a vessel loses control.
BRIDGE SYMBOLS AND DESCRIPTIONS
To quickly learn the four basic bridge shapes—fi xed, bascule, swing, and lift —locate
the line that crosses open water on your nautical chart.
Bridge Symbols
Bridges that do not move are fi xed bridges—they show no center span marks
over open water. Bridges that move are one of three types: bascule bridges (draw-
bridges) show a gap between center span marks; swing bridges show the center
span turned 90 degrees; and lift bridges show two small arcs to mark the center
span. (See illustration.)
Bridge Descriptions
Fixed bridges. Th e vertical height of the bridge is marked next to the charted
symbol. Th at height doesn’t take into account extreme tides at high-water
springs. Check the state of the tide and clearance gauge before passing through.
Fixed bridges have a central main channel and may have one or more auxiliary
channels.
Swing
BridgeBascule
BridgeLift
BridgeThese “hinged” bridges
are very common
in the ICW...Boat traffic moves in
one-way lanes through
these bridges...An “elevator-like”
bridge...Your chart might
show one of these
three symbols ...Fixed
BridgesTh e most common bridge symbols on a nautical chart.