Glossary of Key Terms


Key Terms


Aqueduct:  An artificial channel for conveying water, typically in the form of a bridge supported by tall columns across a valley.  [Oxford Dictionary]


Aquifer:  Underground layer of permeable rock capable of storing water (example: sandstone).  [USGS]


Barrage (dam):  a type of diversion dam on a river consisting of multiple gates to control stream flow for the purpose of regulating water height. Raising and lowering the water height controls the diversion of water into irrigation canals located upstream from the dam.   [Wikipedia


Canal:  Artificial channel constructed for the purpose of transporting water. The canal may be lined with concrete or some other material to prevent water loss due to seepage into the ground. 


Cascade:  Steep section of open canal where water flow resembles water falling down a rocky slope. May also refer to a concrete pad designed to break the momentum of water flowing from a canal or pipeline into a storage reservoir to reduce erosion.


Diversion:  Any type of engineering structure designed to redirect water flow from a river to a canal, a canal to a river, canal to canal, etc… (e.g., headworks, turnout).


Groundwater Recharge Site:  Area where water is released at the surface and allowed to percolate down into an aquifer. The primary purpose may be to restore/improve environmental health, or to store the water temporarily for later use.   [USGS


Headworks:  Any engineering structure at the head or diversion point of a waterway.  Typically includes sluice gates (i.e. sliding gates) for controlling water flow and diverting water from a river to a canal, or from a larger canal to a smaller canal.  [Wikipedia]


Hydroelectric Power Plant:  Also known as a hydro-power plant, it is a structure designed to generate electricity by using water to turn a turbine. Typically found at dams for generating power when water is released. IBTs designed for water supply that flow downhill typically have one or more to take advantage of the opportunity to generate power; whereas, some IBTs are designed with power generation as the primary purpose.  [USGS


Impoundment:  Artificial lake — See Reservoir.


Intake Tower:  Vertical pipe structure in a reservoir near the dam with openings at the top, and possibly lower down, for capturing water at or near the surface to avoid debris at the bottom. The water is then transported to the downstream side of the dam to avoid opening the spillway, which is typically used to regulate the water level of the reservoir only. The water may also be transported to a hydroelectric plant or treatment plant.  [Wikipedia


Penstock:  Pipe structure connecting a surge tank to a hydropower plant that is used to control the flow of water into the power plant.    [Energy Education]  


Pumping Plant:  Pump structure designed to “lift” water upslope.  Typically used in canals to lift water from a section at a lower elevation to the next section at a higher elevation.  [Water Education]  


Pump Generating Plant:  Pumping plant that also has the capability to generate hydroelectricity when the water flow is reversed. Typically found at reservoirs where the plant “lifts” water up to the reservoir for storage, and then generates electricity when the water is released back to the system.   [US Bureau Reclamation]  


Reservoir:  Artificial lake used mostly for water storage, typically constructed by damming a river.  [Wikipedia]


Surge Tank:  Standpipe structure at the down-slope end of a closed section of an IBT designed to absorb any rapid rise in pressure of water flowing down the pipe or tunnel. It can also serve as a storage reservoir for a hydropower plant located just below the structure, and is connected to the hydropower plant by a pipe called a penstock.  [Wikipedia]


Tunnel:  Opening dug through a hill or mountain obstructing the route of an IBT. The tunnel may be lined with concrete to prevent damage to the tunnel walls and reduce water loss.


Turnout:  Sluice gate (i.e., sliding gate) structure for diverting water from a canal to a secondary canal or pipe.


Weir:  Low barrier across a river that alters stream flow, typically designed to hold some water behind the dam-like structure while allowing some to flow over the top and continue downstream.  [Wikipedia]