Design Guide

Application Rate — the rate at which a subsurface grid applies water to a
specific zone, over a given period of time, measured in inches per hour.
Backflow Prevention Device — the device, required by law, on an irrigation
system that prevents water from re-entering the potable water lines once it
flows into the irrigation pipes.
Blackwater — wastewater from toilet, latrine, and agua privy flushing and sinks
used for food preparation or disposal of chemical or chemical-biological
ingredients.
BOD— the abbreviation for “Biochemical Oxygen Demand;” a measure or the
amount of oxygen required to neutralize organic wastes.
Controller — the device that sends timing commands to remote control valves
for actuation.
Design Operating Pressure — the pressure a designer uses to determine spacing
distances and flow for driplines. The design operating pressure is determined
by subtracting estimated friction losses from the static water pressure.
Dynamic Pressure — the pressure reading in a pipeline system with water
flowing.
Effluent Water — any substance, particularly a liquid, that enters the
environment from a point source. Generally refers to wastewater from a
sewage treatment or industrial plant.
Emitter — a device used to control the rate at which water is applied to a
specific area. Emitters are usually injection molded out of chemical-resistant
plastics and come in both inline and online configurations. Toro dripline is
manufactured with factory-installed, inline emitters.
Evapotranspiration — the combined rate at which water evaporates into the
atmosphere and/or is consumed by plants.
Flow — the movement of water through the irrigation piping system.
Flush Cap — a device used to automatically flush sediment and debris from
driplines within a grid. Flushing occurs at the beginning of each irrigation
cycle and ends as soon as the system operation pressure reaches 10 PSI.
Flush Manifold — the end line or pipe in a subsurface grid that connects to all
the driplines. A flush valve and/or cap is installed in the manifold to flush
debris and sediment from the grid during each irrigation cycle.
FPS — the abbreviation for “feet per second;” refers to the velocity of water
in pipes.
Friction Loss — the loss of pressure (force) as water flows through the
piping system.
GPH — the abbreviation for “gallons per hour;” unit of measure for water flow.
GPM — the abbreviation for “gallons per minute;” unit of measure for
water flow.
Greywater —wastewater from washing machines, showers, bathtubs, lavatories
and sinks that are not used for disposal of chemical or chemical-biological
ingredients.
I.D. — the abbreviation for “inside diameter.”
Lateral — the pipe in an irrigation system located downstream from the remote
control valve. Lateral pipes carry water directly to a zone.
Main Line — the pipe in an irrigation system that delivers water from the
backflow prevention device to the remote control valves. This is usually the
largest pipe on the irrigation system, generally under constant pressure and
located upstream from the remote control valves.
Terminology
Landscape Dripline Design _____________________________________________________________
■ Terminology
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