a
Optional Water Efficiency Measure: May contribute to the 30 percent water efficiency requirement,
depending on the chosen WaterSense® Approved Certification Method (WACM).
jIl
III
UNDERSTAND
Different landscape types can be watered most
efficiently with various types of irrigation
equipment. Spray irrigation is best suited for
turfgrass, as it can be designed to distribute water
evenly over uniform turfgrass areas. It is not
optimal for planted beds, since the varied heights
of shrubs and trees can obstruct the spray from
sprinklers. Spray sprinklers consist of a body and a
nozzle.
Spray sprinklers with excessive incoming pressure
can waste water due to misting, overspray, and
uneven coverage. This could also result in product
failure.
Pressure can be regulated by WaterSense labeled
spray sprinkler bodies, which have integral
pressure regulation, or with a pressure-regulating
valve on the irrigation system. These solutions
provide for consistent flow of water and ensure a
more uniform distribution of water on the
landscape.
WaterSense labeled spray sprinkler bodies are
certified to provide pressure regulation, resulting in
a consistent flow rate, in accordance with the
WaterSense Specification for Spray Sprinkler
Bodies.
To maximize water efficiency, ensure the irrigation system has matched precipitation nozzles. A spray
sprinkler nozzle's precipitation rate is the speed at which water is applied to a specific area of the
surrounding landscape.
BUILD
SPECIFY models of spray sprinkler bodies that have earned the WaterSense label, using the
WaterSense Product Search Tool at www.epa.gov/watersense/product-search for reference.
WORK with an irrigation professional certified by a WaterSense labeled program (found at
www.epa.gov/watersense/findapro) to design and install the irrigation system.
INSTALL either WaterSense labeled spray sprinkler bodies or a pressure-regulating valve to maintain
recommended operating pressure.
What Is Matched Precipitation?
When all spray sprinkler nozzles within the
zone/system have the same precipitation rates,
they are said to have "matched precipitation."
Designing a system with matched precipitation
rate heads/nozzles can save water by ensuring
that all areas of the landscape are watered at the
same rate. This limits brown spots and prevents
the homeowner from applying extra water to
alleviate those brown spots.
Other Water-Saving Features
In addition to integral pressure regulation,
sprinkler bodies may have optional features such
as flow reduction capabilities, integral check
valves, and attributes to indicate reclaimed water
use. Flow reduction prevents water from flowing
when a sprinkler is broken or damaged. An
integral check valve prevents water from flowing
out of the system at lower elevations. Both are
beneficial for operating an efficient irrigation
system.

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SPECIFY and INSTALL spray sprinkler nozzles with
matched precipitation to deliver enough water to
cover the entire area of the landscape. This is
especially important when a landscape has
sprinklers with varying coverage (e.g., half- and
quarter-arc sprinklers).
o Ensure matched precipitation throughout each
spray irrigation zone by installing nozzles from
the same model family produced by the same
manufacturer. For matched precipitation,
sprinkler spacing must be consistent, flow rates
must be based on coverage, and the pipes need
to deliver water at a uniform pressure to each
sprinkler.
o See "What Is Matched Precipitation?" on the previous page for more details.
ENSURE that spray sprinkler bodies have a four-inch or greater pop-up height, as they need a certain
amount of clearance over the turfgrass surface to operate correctly.
AVOID using turfgrass and spray irrigation on strips less than four feet wide, because it is difficult to
irrigate narrow strips efficiently without creating overspray.
RESTRICT installation of spray irrigation on slopes in excess of four feet of horizontal run per one foot
vertical rise (4:1 or 25 percent), because the flow rates associated with sprinklers are often a source of
runoff on steep slopes.
VERIFY
CONFIRM that spray sprinkler bodies are WaterSense labeled. Use the WaterSense Product Search
Tool at www.epa.gov/watersense/product-search to search for the makes and model numbers for all
spray sprinkler bodies installed in the landscape.
VERIFY that pressure-regulating valves are regulating to the appropriate operating pressure
recommended for the spray sprinkler nozzles, if applicable.
IDENTIFY whether spray sprinkler nozzles have matched precipitation using manufacturer
specification sheets or other literature. Verifiers can suggest changes that can help achieve matched
precipitation.
CHECK that the station or zone pressure is within
plus or minus 10 percent of manufacturer-
recommended operating pressure for the installed
product (e.g., spray sprinkler body and nozzle).
Verifiers can test a representative zone of the
irrigation system.
Learn More
Visit WaterSense's Spray Sprinkler Bodies
web page at www.epa.gov/watersense/spray-
sprinkler-bodies to learn more.
*NOTE: Consult with the Home Certification Organization for specific verification protocols.
This technical fact sheet is part of EPA's Technical Reference Manual for
WaterSense Labeled Homes. For the full document and other tools and	EPA-832-F-23-016
resources for homes, visit www.epa.gov/watersense/tools-and-resources.	July 2023

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