Hydroelectric systems and dams:
Penstocks for hydroelectric installations are normally equipped with a gate system and a surge tank. Flow is regulated by turbine operation and is nil when turbines are not in service. Penstocks, particularly where used in polluted water systems, need to be maintained by hot water washing, manual cleaning, antifouling coatings, and desiccation.
The term is also used in irrigation dams to refer to the channels leading to and from high-pressure sluice gates.Penstocks are also used in mine tailings dam construction. The penstock is usually situated fairly close to the centre of the tailings dam and built up using penstock rings. These control the water level, letting the slimes settle out of the water. This water is then piped under the tailings dam back to the plant via a penstock pipeline.