Irrigation System Flashcards
Goal of today’s irrigation designer
To produce a system that keeps the landscape green while conserving water and keeping costs down
Entire pipe, valve, control, monitoring, instrumentation, water emission device (sprinklers, emitters, bubblers), and related component package used to deliver water to the landscape
Irrigation system
Water emission device that throws water through the air with a predictable pattern and radius
Sprinkler
The distance a sprinkler will throw and still apply 0.1 inch in an hour at the outside extent of the radius
Effective radius of throw
The smallest orifice of the water flows through in a sprinkler irrigation system
Nozzle
Devices that would cause the sprinklers to operate fairly consistently, even if pressure varies; compensates for varying pressure within the lateral and causes the nozzle to flow at or near the nominal flow rate
Pressure compensating devices
Established by either the mechanical setting of the sprinkler itself, or, in the case of pop-up spray, the nozzle pattern
Arc
Synonymous with the rate that rain falls, the rate which is expressed as a depth of application in one hour or inchers per hour; the rate at which overlapping sprinklers apply water
Precipitation rate
Term used for sprinkler nozzles that have precipitation rates close enough to be used together on a single lateral
“Balanced”
Commonly used uniformity parameters to compare various sprinkler-pressure-nozzle combinations
Christiansen's coefficient of uniformity (CCU) Distribution uniformity (DU) Scheduling coefficient (SC) - most accepted
Water emission devices that tend to bubble water directly to the ground or that throw water a short distance, on the order of one foot, before water contacts the ground surface
Bubblers
Commonly applied in landscape shrub beds, and uses water emission devices called emitters, which have low flow rates, on the order of 0.5 to 2 gallons per hour; a system that employs a small-diameter polyethylene or flexible PVC hose with emitters
Drip irrigation
A control device that can be opened, either automatically or manually, thereby causing water to flow
Valve
Synonyms of an automated valve
Remote control valve
Solenoid valve
Electric valve
Automated control valve
A single remote control valve located at the water source; provides a safety feature and is opened only when other remote control valves in the system are programmed to open; wasted water from mainline failure can be prevented or minimized; if desired to be part of the POC assembly, it would be locate immediately downstream of the BPD
Master valve
A heavy-duty, bronze ball valve that is opened or closed by rotating the handle through 90 degrees; often used as the main shutoff valve for the system, and is located near the street curb
Curb stop valve
Area wherein valves are generally installed in, to protect them, and to make it easy to locate them over time
Valve box
An electric panel designed to apply 24-volt AC across a given station on the controller in order to open a valve or valves in a programmed sequence; powered by 110-volt AV but outputs 24-volt AC power to a terminal strip, and hence, to valves
Irrigation controller
Generally runs on a microcomputer and provides program changes and rain shutdowns from a central location using radio or telephone as a communication link
Central control system
The basic hardware required in the field, and at individual sites, to communicate back to the central control system
Satellite controller
The portion of the irrigation pipe network that is pressurized all or most of the time; the pipe network beginning at the water source and continuing downstream but upstream of the lateral remote control valve
Mainline pipe
The pipe network downstream of the remote control valve and delivering water to water emission devices; pressurized only when the it’s remote control valve is open
Lateral pipe
The flexible, black pipe that comes in rolls; connected using mechanical or threaded fittings
Polyethylene (PE) pipe
Rigid, white pipe that comes in 20-foot lengths; connected using glued or threaded fittings
Polyvinyl chloride (PVC) pipe
Isolating mainline pipe in logical subsections
Isolation gate valves
Often located on the mainline at point where incidental water may be needed for maintenance purposes; good to locate near other equipment and valve boxes
Quick coupler valves
A series of fittings and nipples designed to move so sprinklers can be set to grade initially and moved over time; protect against breakage due to heavy mowing equipment; used to attached sprinklers and other water emission devices to the lateral pipe
Swing joint
Factory-made swing joints
Prefabricated swing joints
A device or assembly to prevent particulate materials from passing
Filter
Type of filter for irrigation systems that are placed at the water source
Primary filtration
Type of filter for irrigation systems that are placed at individual laterals in the system
Secondary filtration
Device used to reduce water pressure to a desired, lower level
Pressure regulator
A component in a pressure regulator which describes how much water will flow through the regulator given the size of the regulator and the difference between upstream and downstream pressure
Pressure falloff curve
A device used to boost existing pressure in a pressurized irrigation system or to create a pressure from a surface water supply
Pump
Typically a centrifugal pump used to increase pressure (not flow) to the minimum appropriate to the irrigation system
Booster pump
A device, possibly a small diaphragm pump or a pressure differential arrangement, which is used to inject water-soluble chemicals into irrigation water at known rate
Fertilizer injector
A mechanical assembly used to prevent potentially contaminated water from flowing out of the irrigation system, and back into a potable water system, due to back pressure or back siphonage; most cases, it is above grade
Backflow prevention device (BPD)
A mechanical device that uses a propeller or other means to measure the volume of water flowing through the pipe per unit of time
Water meter
A known point, available to the contractor, from which the irrigation system will be built; the term is contractual in many instances, as it defines the contractor’s starting point and the point from which the contractor can expect a minimum available flow and pressure; its size is dictated by the size of the “tap” into the water supply or the size of the water meter
Point of connection (POC)
A common POC with landscape irrigation systems
A cap or threaded connection immediately downstream of the project’s water meter
The inherent force of the water created by a pump or relative vertical position below a free water surface
Pressure
Pressure calculations for no-flow conditions; a good example is an irrigation system with all valves closed
Static hydraulics
Pressure calculations under flowing conditions
Dynamic hydraulics
The evaporation from the soil surface plus the transpiration through the plant
Evapostranspiration
A device monitoring system used to measure the evapotranspiration (ET) rate using a container closed at the bottom and with the top flush with surrounding grade and planted with turf
Lysimeter
Terms to avoid
Heads - sprinklers
Zones - laterals
Circuiting - lateral layouts
Clock - irrigation controller
Units of measure for flow
QGallons per minute (GPM)
Gallons per hour (GPH)
Units of measure for velocity
VFeet per second (FPS)