
Miners working a small sluice on Lucky Gulch, Alaska
A 'sluice' is a water channel that is controlled at its head by a gate. For example, a 'millrace' is a sluice that channels water toward a
water mill.
A 'sluice gate' is traditionally a wooden or metal plate which slides in grooves in the sides of the channel. Sluice gates are commonly used to control water levels and flow rates in
rivers and
canals. They are also used in wastewater treatment plants and to recover minerals in
mining operations.
Operation
Raising a sluice gate allows water to flow under it. (The term ''sluice gate'' refers to any gate that operates by allowing water to flow under it.) When a sluice gate is fully lowered, water sometimes spills over the top, in which case the gate operates as a
weir.
Usually a mechanism drives the sluice gate up or down. This may be a simple, hand-operated, worm drive or
rack and pinion drive, or it may be electrically or
hydraulically powered.
The gates of a
lock may work in a way similar to the way a sluice gate works, but traditional canal lock gates are hinged to swing like double doors.
Types of sluice gates
★ 'flap' sluice gate — a fully automatic type, which is controlled by the pressure head across it. It is a gate hinged at the top. When pressure is from one side, the gate is kept closed. A pressure from the other side opens the sluice when a threshold pressure is surpassed.
★ 'vertical rising' sluice gate — a plate sliding in the vertical direction, controlled by machinery.
★ 'radial' sluice gate — a structure, where a small part of a cylindrical surface serves as the gate, supported by radial constructions going through the cylinder's radius. Occasionally a counterweight is provided.
★ 'rising sector' sluice gate — also a part of a cylindrical surface, which rests at the bottom of the channel and rises by rotating around its centre.
★ 'needle' sluice — a sluice formed by a number of thin needles held against a solid frame through water pressure as in a
needle dam.
See also
★
Canal lock
★
Floodgate
★
Slussen
★
Mining
External links
★
Soar Valley Sluice Gates
★
Salt/Fresh water separating Sluice Complex (Part of DeltaWorks)