UPSTREAM : The part of a stream of water between a given point and the source.

BRIDGE ARCH : A bridge arch under which a boat has to pass.

DOWNSTREAM : The lower part of a water stream, of a valley: the side toward which the water stream descends.

LOCK WALL : Masonry side walls of a lock.

REACH : Part of a canal or river included between two locks or two dams.

BOLLARD: Mooring element on land or on a boat.

VNF channel : Preset radio frequency band for navigation.

CHANNEL : Navigable part of the river where boats must navigate.

IDLE TIME : Interruption of navigation for works. Waterway idle time dates are set by ministerial decision.

LATCH KEEPER : Peg used to lock the operating crank of manual locks.

P.H.E.N.: Highest waters beyond which river navigation is interrupted. These are announced to inland water shipping by notice.

FENDERS : Balloons used to protect the hull against impacts. They must be floatable.
OVERFLOW WEIR : Part of a fixed or mobile dam.

NAME : A boat’s christening name.

BREASTING POLE : Wooden or metal pole used to keep the boat a certain distance from the banks.

CHAIN OF LOCKS : Sequence of locks very close to each other so the canal can pass through a high gradient.

LOW WATER : Lowest water levels of a course of water.

WAY : Speed acquired by a boat after engines are stopped.

DRIFTING : Navigation of the boat with the current with engines stopped.

SHEET PILE BULKHEAD : Metal device protecting the bank.

RISER : Element secured nearby a lock to trigger the opening of the gates of an automated lock.

GUARD GATES : Lock gates used only in a flood period to isolate the flood bypass channel.

 

LOCK SILL : Lock bottom masonry under the gates.

LOCK CHAMBER : Space between the upstream and downstream gates of a lock.

CLEARANCE or AIR SPACE : Speaking of a bridge, the clearance is the available height between the water level and the keystone. Speaking of a boat, the air space is the vertical distance between the water plane and the highest point of the boat.

DRAFT: Distance the boat reaches under the waterline.

OVERTAKING : Act of overtaking another boat.

GATE : Mobile part of the lock doors. There are doors with one or two gates.

WATER-GATE : Vertical valve in a lock door used to fill or empty the chamber.