Terminology

Word Description Alternative names
Actuation system The method by which water control gates are opened and closed. May be a manually operated or control gates are opened and closed. May be a manually operated or mechanised. Actuator, winch
Border check irrigation A form of irrigation used on extremely flat pasture where water is delivered via pipe or open channel to one end of the pasture from where it flows across the surface until it reaches the other side. Flood irrigation, border check irrigation
Bottom Valve A valve used in the bottom of waterways and pits to isolate or cover drain lines. Riser, sludge plug, Mud valve
Canal A formed ditch designed to carry water. May be earthen or lined with concrete. Channel, delver, delva, spur, ditch
Channel A formed ditch designed to carry water. May be earthen or lined with concrete. Delver, delva, spur, ditch, canal
Decant weir Downwards-opening overshot gate. Overshot weir, Downwards-opening penstock, Fixed-base overshot
Delva A formed ditch designed to carry water. May be earthen or lined with concrete. Channel, delva, spur, ditch, canal
Ditch A formed ditch designed to carry water. May be earthen or lined with concrete. Channel, delva, delva, spur, canal
Downwards-opening penstock Downwards-opening overshot gate. Fixed-base overshot, Decant weir, Overshot weir
Drop bar A regulating structure historically fitted to open channel systems where the water flow/level is controlled by inserting horizontal wooden slats into a frame to effectively raise or lower the height of the gate.  
Drop leaf (gate) A water regulating structure pivoted at the base to allow water to flow over the top at a set depth. They are a common fixture in open channel systems. LayFlat, tilting weir
Drowned (situation) Where the upstream and downstream water levels of an open waterway control structure are equal to each other. Submerged
Electromagnetic flow meter A non-intrusive flowmeter based on Faraday's Law of Magnetic Induction. In a magnetic flowmeter, the liquid acts as a conductor as it flows through the pipe. This induces a voltage which is proportional to the average flow velocity - the faster the flow rate, the higher the voltage. This voltage is picked up by sensing electrodes mounted in the meter tube and sent to the transmitter which takes the voltage and calculates the flow rate based on the cross sectional area of the meter tube. Magmeter, Mag flow meter
EPDM (rubber) Ethylene Propylene Diene Monomer rubber is an elastomer which is characterised by wide range of applications, particularly for water tight seals.  
Fixed-base overshot Downwards-opening overshot gate. Downwards-opening penstock, Decant weir, Overshot weir
Flood irrigation A form of irrigation used on extremely flat pasture where water is delivered via pipe or open channel to one end of the pasture from where it flows across the surface until it reaches the other side. Border check irrigation, precision surface irrigation.
Gate flap A regulator structure generally used in open waterway situations that allows water to flow in one direction, but not in the other. Non-return gate flap, Tidal gate
Gigalitre One million megaltres (the equivalent of 444 olympic-sized swimming pools). GL
GL Gigalitre = one million (1,000,000) megalitres. The equivalent of 444 olympic-sized swimming pools. Gigalitre
HDPE High Density Poly Ethylene. Standard material used in the construction of large irrigation and water delivery pipes. PE, poly, polyethylene
Head & discharge (gate) A two-piece vertical water control gate where the water flow or level is controlled by lowering the top half of the gate so water flows over the structure (head) or by raising the lower half of the gate so the water flows under (discharge). Under/over gate, head and orifice gate
Head & orifice (gate) A two-piece vertical water control gate where the water flow or level is controlled by lowering the top half of the gate so water flows over the structure (head) or by raising the lower half of the gate so the water flows under (discharge). Under/over gate, head and discharge
Head pressure The force exerted at a certain point due to the columnar height of water above that same point.  
LayFlat (gate) A water regulating structure pivoted at the base to allow water to flow over the top at a set depth. They are a common fixture in open channel systems. Tilting weir, Drop Leaf
Mag flow meter A non-intrusive flowmeter based on Faraday's Law of Magnetic Induction. In a magnetic flowmeter, the liquid acts as a conductor as it flows through the pipe. This induces a voltage which is proportional to the average flow velocity - the faster the flow rate, the higher the voltage. This voltage is picked up by sensing electrodes mounted in the meter tube and sent to the transmitter which takes the voltage and calculates the flow rate based on the cross sectional area of the meter tube. Electromagnetic flowmeter, magmeter
Mag meter A non-intrusive flowmeter based on Faraday's Law of Magnetic Induction. In a magnetic flowmeter, the liquid acts as a conductor as it flows through the pipe. This induces a voltage which is proportional to the average flow velocity - the faster the flow rate, the higher the voltage. This voltage is picked up by sensing electrodes mounted in the meter tube and sent to the transmitter which takes the voltage and calculates the flow rate based on the cross sectional area of the meter tube. Electromagnetic flowmeter, mag flow meter
Mains powered Electrical power source obtained by being connected to the electrical power grid. In Australia this is either 240VAC 50Hz (single phase) or 415VAC (three phase).  
Megalitre One million litres. ML
ML Megalitre = one million (1,000,000) litres. Megalitre
MPI A device used to count the number of turns of a winch or actuator system which can in turn be used to determine how open (or closed) a water control device is at any given time. Potentiometer
Mud Valve A valve used in the bottom of waterways and pits to isolate or cover drain lines. Riser, sludge plug, bottom valve
Non-return gate flap A regulator structure generally used in open waterway situations that allows water to flow in one direction, but not in the other. Gate flap, Tidal gate
Non-rising(spindle) Where a threaded vertical shaft operates the water control gate and does not rise with the door as it lifts.  
Orifice gate A vertical water control gate placed in a channel, flume or piped system where the water flow or level is controlled by lifting the gate vertically in such a way that the water flows through the opening at the bottom of the structure. Undershot gate, slide gate, sluice gate, Penstock, PosiSeal, door, gate,
Overshot weir Downwards-opening overshot gate. Decant weir, Downwards-opening penstock, Fixed-base overshot
PE HDPE. High Density Poly Ethylene. Standard material used in the construction of large irrigation and water delivery pipes. HDPE, poly, polyethylene
Penstock A vertical water control gate placed in a channel, flume or piped system where the water flow or level is controlled by lifting the gate vertically in such a way that the water flows through the opening at the bottom of the structure. Undershot gate, slide gate, Orifice gate, PosiSeal, sluice gate, door, gate,
Poly HDPE. High Density Poly Ethylene. Standard material used in the construction of large irrigation and water delivery pipes. HDPE, PE, polyethylene
Potable Water suitable for drinking by humans. Drinking water, fresh water
Potentiometer A device used to count the number of turns of a winch or actuator system which can in turn be used to determine how open (or closed) a water control device is at any given time. MPI
Precision surface irrigation A form of irrigation used on extremely flat pasture where water is delivered via pipe or open channel to one end of the pasture from where it flows across the surface until it reaches the other side. Flood irrigation, precision surface irrigation
Radial Gate A water regulation structure that utilises a section of a large cylinder with the axis lying horizontally across the channel. A disinctive feature of this structure is the large pair of support arms between the curved door section and the axis point located on the downstream side. Tainter Gate
Retrofit Updating an existing structure by fitting a new item to existing infrastructure.  
Riser A valve used in the bottom of waterways and pits to isolate or cover drain lines. Sludge plug, Mud valve, bottom valve
Rising (spindle) Where a threaded vertical shaft operates the water control gate and rises with the door as it lifts.  
SCADA Supervisory Control And Data Acquisition. A control system generally used where large amounts of items or structures need to be monitored and controlled. Data is transmitted in both directions.  
Side slide gate A vertical water control gate placed in a channel, flume or piped system where the water flow or level is controlled by opening the gate to the side. Used in situations where overhead projection of the gate is a concern. SideWinder
SideWinder A vertical water control gate placed in a channel, flume or piped system where the water flow or level is controlled by opening the gate to the side. Used in situations where overhead projection of the gate is a concern. Side slide gate
Slide gate A vertical water control gate placed in a channel, flume or piped system where the water flow or level is controlled by lifting the gate vertically in such a way that the water flows through the opening at the bottom of the structure. Undershot gate, sluice gate, Penstock, Orifice gate, PosiSeal, door, gate,
Sludge plug A valve used in the bottom of waterways and pits to isolate or cover drain lines. Mud valve, Riser, bottom valve
Sluice gate A vertical water control gate placed in a channel, flume or piped system where the water flow or level is controlled by lifting the gate vertically in such a way that the water flows through the opening at the bottom of the structure. Undershot gate, slide gate, orifice gate, Penstock, PosiSeal, door, gate,
Solar powered Electrical power source usually consisting of a solar panel (photovoltaic cell) and a DC battery. In commercial use, voltages are usually 12VDC or 24VDC.  
Spindle A threaded bar that lifts or lowers a gate by being rotated in such a way that the thread acts upon a matching threaded block where the rotational action is converted to (usually) vertical force.  
Submerged (situation) Where the upstream and downstream water levels of an open waterway control structure are equal to each other. Drowned
Tainter Gate A water regulation structure that utilises a section of a large cylinder with the axis lying horizontally across the channel. A disinctive feature of this structure is the large pair of support arms between the curved door section and the axis point located on the downstream side. Radial Gate
Telemetry The measurement of data at a remote source and transmission of the data (typically by radio) to a monitoring station.  
Tidal gate A regulator structure generally used in open waterway situations that allows water to flow in one direction, but not in the other. Non-return gate flap, Gate flap
Tiliting weir (gate) A water regulating structure pivoted at the base to allow water to flow over the top at a set depth. They are a common fixture in open channel systems. LayFlat, drop leaf
UHMWPE Ultra High Molecular Weight Poly Ethylene. A hard-wearing high density plastic with low-friction attributes.  
Under/over (gate) A two-piece vertical water control gate where the water flow or level is controlled by lowering the top half of the gate so water flows over the structure (head) or by raising the lower half of the gate so the water flows under (discharge). Head & Discharge, head & orifice
Undershot (gate) A vertical water control gate placed in a channel, flume or piped system where the water flow or level is controlled by lifting the gate vertically in such a way that the water flows through the opening at the bottom of the structure. Penstock, slide gate, Orifice gate, sluice gate, PosiSeal, door, gate,

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