EPA
Water Sense
Water Efficiency Management Guide
&EPA
EPA 832-F-17-016b
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The U.S. Environmental Protection Agency (EPA) WaterSense® program encourages property
managers and owners to regularly input their buildings' water use data in ENERGY STAR® Portfolio
Manager®, an online tool for tracking energy and water consumption. Tracking water use is an
important first step in managing and reducing property water use.
WaterSense has worked with ENERGY STAR to develop the EPA Water Score for multifamily
housing. This 0-100 score, based on an entire property's water use relative to the average national
water use of similar properties, will allow owners and managers to assess their properties' water
performance and complements the ENERGY STAR score for multifamily housing energy use.
This series of Water Efficiency Management Guides was developed to help multifamily housing
property owners and managers improve their water management, reduce property water use, and
subsequently improve their EPA Water Score. However, many of the best practices in this guide
can be used by facility managers for non-residential properties.
More information about the Water Score and additional Water Efficiency Management Guides are
available at www.epa.qov/watersense/commercial-buildinqs.
EPA

WaterSense

ENERGY STAR
Landscaping and Irrigation Table of Contents
Background	1
Understanding Outdoor Water Use	1
Seasonal Comparison	2
WaterSense Water Budget Tool	3
System Input Methodology	3
Landscaping			4
Site Preparation 				4
Plant Selection	4
Other Landscape Features	5
Landscaping Maintenance Best Management Practices	6
Irrigation	7
Irrigation System Controllers and Sensors..																					7
Irrigation System Components			8
Irrigation Maintenance Best Management Practices	9
Water Savings	10
Irrigation Controllers																													 11
Spray Sprinkler Bodies	11
Additional Resources	13
Appendix A: Summary of Water Efficiency Measures and Savings	A-1
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Background
Residential outdoor water use in the United
States accounts for more than 9 billion gallons of
water used each day, mainly for landscape
irrigation. It is estimated that as much as 50
percent of the residential outdoor water we use
is wasted through evaporation, wind, or runoff,
due in part to improper irrigation system design,
installation, and maintenance. Irrigation systems
can water too much or too often, and equipment
can wear over time. Improved landscaping,
sound maintenance practices, and efficient
irrigation equipment can significantly reduce
water use and costs from property landscapes.
Typically, landscape watering is meant to supplement natural precipitation based on the
plants' water needs. In some areas of the country, such as the arid Southwest, this gap in
water needs and precipitation can be significant during certain times of the year. Not
surprisingly, in larger properties with larger areas of maintained and irrigated landscape, as
much as 30 percent of the water bill goes to maintain the landscape. In many instances,
outdoor water use can be controlled and minimized with proper landscape design.
Regionally appropriate plant choices, healthy soils with appropriate grading, use of
mulches, and limiting the use of high water-using plants can significantly reduce the need
for supplemental irrigation. In addition, proper design, installation, and maintenance of the
irrigation system can reduce outdoor water use.
A variety of irrigation technologies can help reduce water use, from drip irrigation to
WaterSense labeled controllers or components. This guide covers how to better assess and
improve water used for irrigating landscapes and reduce operating costs, all while
enhancing plant health and curb appeal.
Understanding Outdoor Water Use
In order to optimize water savings on multifamily properties, it is important to first
understand how much water is being applied to the landscape. Outdoor water use is
determined by: landscape size; plant palette; local climate; irrigation efficiency (a result of
system design, equipment, and installation); and human behavior (e.g., desire for
aesthetics, irrigation scheduling, system maintenance).
Dedicated irrigation meters can track irrigation water use and allow property managers to
document actual savings. WaterSense strongly recommends installing and monitoring a
dedicated meter or submeter for your irrigation system, as this is by far the most effective
way of determining outdoor water use.
Several other (but less accurate) methods can be used to estimate irrigation water use if a
submeter is not an option for your property. However, it is important to remember that these
calculation methodologies only provide estimates of irrigation water use and can vary
greatly from the amount of water your property actually uses. These estimates should only
be used to examine possible savings of recommended practices or products. An irrigation
system is just that—a system where all of the components must be optimized in tandem in
order to realize maximum water savings.
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Seasonal Comparison
By comparing the amount of water used during actual irrigation seasons to other times of
the year, you can determine the amount of water used for irrigation throughout the year. For
example, if irrigation only occurs from April through September, monthly water use is likely
to be both higher and more variable in those months and lower/more constant from October
through March. The difference between those two periods should be approximately equal to
your property's total annual irrigation water use.
Note, however, that if other sources use water seasonally (e.g., cooling tower make-up
water in the summer), this method may be less effective, as distinguishing between
seasonal uses is impossible using billed water use information alone.
Example:
Table 1 represents water usage data for a multifamily property, pulled from monthly water
utility bills. This information is illustrated in Figure 1 to the right of Table 1.
Table 1 and Figure 1. Example Monthly Property Water Use
Month
Water Use (gallons)
January
53,000
February
52,000
March
61,000
April
73,000
May
86,000
June
97,000
July
112,000
August
108,000
September
75,000
October
60,000
November
55,000
December
49,000
Total
890,000
120,000
100,000
80,000
60,000
40,000
Baseline use
(non-irrigation)
20,000

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this method. In this example, if the cooling tower operates during a similar season (April
through September) and the make-up line submeter indicates 150,000 gallons used for the
year, subtract that amount from the 230,000 gallons of seasonal water use.
230,000 gallons - 150,000 gallons = 80,000 gallons use for irrigation per year
This same methodology can be used regardless of your irrigation season. Simply average
the monthly water use across the number of months that you know your property is not
irrigating, then follow the same steps to estimate your seasonal water usage.
WaterSense Water Budget Tool
The WaterSense Water Budget Tool, available both online and as a Microsoft Excel
spreadsheet on the WaterSense website,1 guides a property manager, landscape
professional, or irrigation professional through the needed calculations to establish a
landscape water budget. This water budget approach not only serves as a design tool,
allowing the user to design a sustainable landscape based on a regionally appropriate
amount of water, but also to alter the irrigation type in a virtual setting and analyze the
relative water savings associated with each design change. While the tool is effective at
indicating the relative efficiency of one set of choices over another, it is not intended to
estimate actual savings. The budget accounts for plant type, plant water needs, irrigation
system design, and applied water that the landscape receives either by irrigation or by
precipitation.
The WaterSense Water Budget Tool guides the user through the water budget calculation
in three parts. First, the tool calculates a baseline amount of water for a landscape and
subsequently an amount of water the designed landscape is allotted in order to be
considered water-efficient. Next, the tool calculates how much water the designed
landscape requires based on climate, plant type, and irrigation system design. Lastly, it
compares the landscape water requirements to the budgeted amount of water to provide
the user with information on the degree of efficiency of the landscape and irrigation design.
It is important to remember that water budgets must be associated with a specified amount
of time, such as a week, month, or year. The WaterSense Water Budget Tool provides the
user with peak month usage (the one month each year when the landscape needs more
supplemental water than any other based on historic data), so scaling up to annual use
should be considered when calculating annual savings.
System Input Methodology
If you do not have a dedicated irrigation meter or submeter, or the seasonal comparison
method or WaterSense Water Budget Tool is not a viable option for estimating your
irrigation water use, it is possible to estimate water use based on the number and type of
emission devices (e.g., sprinklers or drip emitters), their associated characteristics (e.g.,
flow rate at the system's operating pressure), and the irrigation schedule. However, due to
the complexity of these calculations, it is recommended that you work with a certified
irrigation professional to collect this information and establish a water use estimate. This
exercise can also be part of an irrigation audit.
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Landscaping
Outdoor water efficiency starts with the
landscape itself. The soil, slopes, plantings, and
placement of foliage can make the difference
between a water-smart landscape and irrigation
inefficiency. This section includes tips on how to
design and maintain your landscaping to use
less water.
Site Preparation
How the site is prepared has a significant impact
on the ability of the landscape to retain moisture
and limit the need for supplemental irrigation.
Whether designing a new landscape or replacing
to prepare the site for water efficiency:
an existing one, following are some ways
•	Limit the removal of native vegetation and soils, because once established, they will
require little water beyond normal rainfall.
•	Minimize soil compaction in the construction phase by limiting areas where heavy
equipment is used.
•	Install temporary protective fencing around trees to protect their root zones.
•	Reduce the potential for runoff from steep slopes in the landscape by either grading
appropriately or terracing. If slopes cannot be avoided in landscape design, install
plants with deeper root zones to provide stabilization and prevent erosion.
•	Before the landscape is installed, ensure that the soil is properly amended, tilled, and
contoured to hold water. Where turfgrass is used, the area should include at least six
inches of well-amended soil capable of easily absorbing and holding water in the root
zone.
Plant Selection
Plant selection can make all the difference in a water-efficient landscape. Converting to a
water-smart landscape through careful plant selection and design can reduce outdoor water
use by 20 to 50 percent. When redesigning a landscape:
•	Evaluate site conditions and plant species that work best in a particular space. Areas of
the same site may vary significantly in soil type or exposure to sun and wind, as well as
evaporation rates and moisture levels.
•	Be mindful of a site's exposure to the elements and choose plants that will thrive in local
climate conditions. Select drought-tolerant or climate-appropriate turfgrass, trees,
shrubs, and ground cover when replanting landscaped areas.
•	Incorporate shade trees into your landscape or plant near large shade trees. Shaded
areas typically require less supplemental water than areas exposed to direct sun.
Additionally, trees and other vegetation placed strategically to shade the south-facing
wall of a building can eventually help to reduce energy costs.
•	Practice hydrozoning, or grouping plants with similar irrigation needs together. Consider
how the interplay between the types of plants and irrigation components can affect the
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volume of water needed to sustain the landscape. For example, turf areas and shrub
areas should always be separated into different irrigation zones to accommodate their
differing water needs.
•	Avoid installing "strip grass" (e.g., small strips
of grass between the sidewalk and street),
because these areas are hard to maintain
and difficult to water efficiently.
•	When designing or revamping a property's landscape, consider installing rain gardens,
bioretention areas, bioswales, or other green infrastructure throughout the landscape.
These features should include locally adapted or appropriate plantings designed to
capture rainwater runoff from roofs, driveways, and sidewalks. These features can keep
water on the property and absorb up to 40 percent more runoff than typical lawns. Rain
barrels and cisterns that capture rainwater can also serve as a supplemental irrigation
water source. Furthermore, green infrastructure can help your property comply with
local regulations and offset stormwater treatment costs.2
Other Landscape Features
While water features are common in many landscapes, consider the annual water use of
the specific feature before installing one. Ideally, these features should provide a beneficial
use, such as a wildlife habitat, stormwater management, and/or noise reduction. Because
some water from these features is lost to evaporation, use alternative water sources or look
for a feature that recirculates water in order to reduce the amount of potable water used.
Smaller pumps, lower pumping rates, and/or pressure-reducing valves can help reduce
water flow. Install and maintain a water recirculation system to minimize the water used by
water features, and set the recirculation system on a timer to turn off at night.
Avoided strip grass.
• Consider reducing the area covered by turfgrass in the landscape, as most turf
generally requires more water than planted beds, especially if the plants are climate-
appropriate and their surrounding soil is
covered with mulch. Use turfgrass where it
serves a practical purpose (e.g., play space
for children and pets) and consider other
plantings for areas that receive little to no foot
traffic or use.
2 EPA. Green Infrastructure, www.epa.aov/areen-infrastructure
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Landscaping Maintenance Best Management Practices
Maintaining the landscape appropriately is just as important as good design when it comes
to water efficiency. Table 2 outlines best management practices that can guide a property
manager in water-efficient landscaping maintenance.
Table 2. Landscape Maintenance Tips for Water-Efficient Landscaping
Item	Tip	Why
Soil
Cover bare soil in plant beds with mulch, and re-
mulch areas annually.
Mulch helps soil retain its nutrients and traps in
moisture while supporting plant growth and
preventing erosion.
Soil
Maintain plenty of good topsoil (about 4 to 6
inches) in landscaped areas.
Topsoil helps capture precipitation as it falls and
releases water back to plants overtime, reducing
water needs.
Soil
Incorporate soil amendments, such as lime,
compost, and shredded bark, into water-logged or
fast-draining soils. Landscapes with clay soils or
sandy soils should incorporate topsoil or compost.
Proper soil water holding capacity prevents soil
from draining too quickly. Adding compost or
similar soil amendments can reduce irrigation water
use by 20 percent annually.
Soil
Aerate areas with heavy foot traffic or where
landscaping equipment is used regularly.
Aeration alleviates compaction and improves water
infiltration rates. It can also improve soil's ability to
hold water.
Plants
Keep the irrigated landscape free of weeds, and
consider pulling manually instead of using
herbicides.
Weeds consume water that could be used by your
plants. Using herbicide to kill weeds can
contaminate local water sources.
Plants
Raise the blade on mowers to allow grass to grow
longer. Mow only when it reaches two to three
inches in height, and remove just one inch.
Longer turfgrass promotes deeper root growth and
more drought-resistant turf.
Plants
Know your plants' water needs and avoid
watering during the heat of the day.
Watering during cooler times of the day, such as
early morning or evening, prevents water loss from
evaporation and protects plants from excessive
heat.
Water features
Check water feature recirculation systems
annually for leaks and other damage, and repair
immediately.
Just like with other water-using equipment, water
features that leak can waste significant amounts of
water.
Green
infrastructure
Clean and maintain green infrastructure features
(e.g., rain gardens, bioretention area, permeable
pavers) as recommended by the designer or state
and local regulations. If at any point you see
standing water in a green infrastructure feature,
contact the design professional or your
maintenance provider to determine how to regain
its functionality.
Sediment can build up in bioretention areas, in
permeable pavers, or at curb cuts, preventing
water from flowing as intended and filtering into the
soil. Good maintenance can prevent erosion and
ensure vegetation continues to thrive and soil
retains filtration characteristics.
Landscape
Professionals
Use landscape professionals trained and certified
in water-efficient or climate-appropriate
landscaping. Existing staff who tend landscapes
can attend courses or seminars to learn water-
efficient techniques.
Periodically review all landscape service and
maintenance agreements to incorporate water,
chemical, and energy efficiency requirements or
performance standards.
Hiring qualified landscape professionals who
specify plants that are low maintenance and do not
require supplementation irrigation will cut down on
costs in the long run. Many landscape
professionals not only install and maintain plants in
your landscape, but also install and maintain the
irrigation system.
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Irrigation
Although it is possible in many parts of the country to design a landscape that can live on
rainfall alone, some irrigation may be needed to ensure landscape health and maintain an
aesthetic property. The key to reducing irrigation water use is to combine efficient irrigation
practices with efficient technologies.
If installing a new or replacing an existing irrigation system, there are many opportunities to
increase its efficiency. Consider installing a separate meter to measure the volume of water
applied to the landscape, which can reduce wastewater costs in some jurisdictions and help
to identify leaks more quickly. Alternative water sources, such as collected rainwater,
condensate from air conditioners, or boiler blowdown, can be used as a substitute for
potable water sources for irrigation.
When installing irrigation equipment, whether new or for replacement, consider
installing WaterSense labeled products, such as irrigation controllers and
spray sprinkler bodies, which are independently certified to meet EPA's
efficiency and performance criteria. These products can increase water
efficiency, provide water cost savings, improve tenant satisfaction, and help
reduce maintenance costs.
You can identify WaterSense labeled irrigation products by using the
WaterSense Product Search Tooj and by looking for the WaterSense label on
product packaging or websites. Be sure to check with your local water utility or
use the WaterSense Rebate Finder to see if there are any rebates available in your area.
Irrigation System Controllers and Sensors
An existing irrigation system can be optimized through retrofits to the control mechanism or
other components. Consider replacing existing clock-timer controllers with more advanced
control systems that water plants only when needed.
•	WaterSense labeled irrigation controllers use
local weather and landscape conditions to
determine when and how much to water. In order
to work effectively, these irrigation controllers
must be installed and programmed properly, so
consider having your controller installed by an
irrigation professional who has been certified
through a WaterSense labeled program (see box
on page 8).
•	Soil moisture-based control technologies can be
inserted into the soil to measure moisture,
regulating irrigation so that it only occurs when
soil moisture falls below a set threshold. These sensors can be connected to an existing
controller or be installed in a new system to enable irrigation as needed by plants.
Studies suggest that soil moisture-based control technologies can result in water
savings of at least 20 percent.3
*
look for
WaterSense labeled Irrigation controller
3 EPA's WaterSense program. Soil Moisture-Based Control Technologies, www.epa.aov/watersense/soil-moisture-based-control-technoloaies
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Work With a Certified Irrigation Pro
•	Alternatively, consider installing rain-sensing
technology to prevent irrigation from taking
place during periods of sufficient rainfall. If a
system irrigates a half an acre of landscape at
34 inch of water per cycle, a single instance of a
rain sensor preventing an irrigation event can
save nearly 6,800 gallons.
•	If managing a large property, consider installing
complete central control systems that use
demand-based controls to enable a water
manager to centrally operate and manage
multiple irrigation systems at multiple locations
with various means of communication.
Irrigation System Components
Individual irrigation system components also offer
water savings opportunities:
•	Consider retrofitting a portion of the spray
bodies that water trees, shrubs, or plant beds
with micro-irrigation or drip irrigation. Many
plant beds do not require the spray heads
traditionally used to water turf areas, and drip
irrigation directs water to plant roots at a low
flow rate, avoiding water lost to wind or runoff.
This technology uses 20 to 50 percent less
water than conventional in-ground or pop-up
sprinkler systems.
Whether designing a new irrigation system,
installing retrofits, or contracting for a system
audit to look for water-saving improvements,
look for an irrigation professional who has
been certified by a program that has earned
the WaterSense label . These professionals
have demonstrated their knowledge of water-
efficient techniques and technologies in
irrigation system design, auditing, or
installation and maintenance. Visit
www.epa.gov/watersense/find-pro to
find a certified professional near you.
Photo credit: Brightview
across the landscape. WaterSense
labeled spray sprinkler bodies can
reduce irrigation water use by 20
percent or more when irrigation
system pressure exceeds 60 psi.4
The image at left shows a spray sprinkler with a body that is non-
pressure-compensating, resulting in water wasted from misting and
overwatering. The image at right shows a pressure-regulating spray
sprinkier body that regulates the water pressure to the sprinkler
nozzle's optimal pressure.
• Landscape irrigation sprinklers are often installed at sites where the system pressure is
higher than what is recommended for the sprinkler nozzle, thus resulting in system
inefficiencies, including excessive flow rates, misting, fogging, and uneven coverage. In
fact, approximately 63 percent of
irrigation systems operate at
pressures higher than the
recommended operating pressure of
sprinkler nozzles, which is around
30 pounds per square inch (psi) for
most products. However, sprinkler
bodies with integral pressure
regulation can provide a constant
flow at the sprinkler nozzle to help
reduce water waste and provide
more uniform distribution of water
4 EPA's WaterSense program. WaterSense Specification for Spray Sprinkler Bodies Supporting Statement. September 21. 2017.
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•	Pay attention to spacing between sprinklers during replacement to ensure the sprinklers
have a matched precipitation rate, have matched trajectories, and offer head-to-head
coverage.
•	Consider installing sprinkler bodies with check valves, as this mechanism allows
sprinklers to retain water in lateral pipes between cycles (rather than draining the water
after the irrigation event), reducing the amount of water needed in the next irrigation
cycle.
•	Retrofit other water-using devices on the property to use water more efficiently. For
example, attach shut-off nozzles to handheld hoses to make sure water is going directly
to the plants rather than dripping on the ground.
Irrigation Maintenance Best Management Practices
Performing periodic inspections of your irrigation system will help keep equipment working
and catch water waste before it impacts your water bill. Aim to conduct inspections at least
annually, especially at the start of the irrigation season. In addition, consider having an
irrigation professional certified by a WaterSense labeled program conduct an irrigation
system audit at least every three years to make sure your system continues to operate
efficiently.
Table 3 outlines best management practices that can guide a property manager in making
more water-efficient landscaping choices.
Table 3. Irrigation Maintenance Tips for Water-Efficient Landscaping
Item
Tip
Why
Irrigation
System
Operation
Have a certified irrigation professional such as
an auditor provide options for automating
schedule changes based on changing weather
conditions. Verify that the irrigation schedule is
appropriate for climate, soil conditions, plant
materials, grading, weather, and season.
Update schedules based on changing weather
and as part of regular maintenance. Installing
and properly programming a WaterSense
labeled irrigation controller or a soil moisture-
based control technology can also provide this
benefit.
Many landscapes are watered at the same level all
year, but landscape water needs change with the
seasons, and so should the irrigation schedule.
Overwatering can damage plants more than
underwatering and can also damage building
foundations. A weather- or soil moisture-based
controller waters plants only when and how much
they need it.
Irrigation
System
Operation
Irrigation may need to be separated into multiple
applications depending on landscape
conditions, also known as a "cycle and soak"
methodology. If your current irrigation
controller(s) are not capable of "cycle and soak
methodology," consider upgrading to more
current technology.
Certain soil types or steep slopes increase the
chance of surface runoff.
Irrigation
System
Operation
Incorporate an outdoor water budget using the
WaterSense Water Budget Tool to a new or
existing landscape.
By identifying an allowable amount of water to be
applied, a water budget can reduce water use on your
landscape.
Maintain the
Irrigation
System
Verify that irrigation system pressure is within
manufacturer specifications for sprinkler nozzles
and adjust accordingly.
Sprinklers that operate at their optimal pressure
reduce misting, fogging, and uneven coverage.
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Table 3. Irrigation Maintenance Tips for Water-Efficient Landscaping
Item
Tip
Why
Maintain the
Irrigation
System
Ask the irrigation professional or staff managing
the system to ensure sprinkler heads are placed
and adjusted to water the lawn or garden only—
not the street or sidewalk.
Periodically monitoring irrigation system for
effectiveness throughout the year reduces water
waste and runoff.
Maintain the
Irrigation
System
To help ensure consistent uniformity, require
replacement equipment (e.g., sprinkler nozzles)
be compatible with existing equipment and
made by the same manufacturer.
Ensuring consistency across equipment results in a
more efficient system.
Maintain the
Irrigation
System
Require a full audit of the irrigation system every
three years by a qualified irrigation auditor, such
as a professional certified by a WaterSense
labeled program.
An in-depth assessment of the irrigation system, its
performance, and schedule will expose deficiencies
that can occur from either system and/or landscape
changes and identify more efficient technologies.
Maintain the
Irrigation
System
Request that staff managing the system
immediately report and repair leaks and other
problems in the system.
A leak about as small as the tip of a ballpoint pen (or
1/32nd of an inch) can waste about 6,300 gallons of
water per month. A drip irrigation system either with a
programming malfunction or leaking at 1.0 gallons per
minute can lose up to 43,200 gallons per month.
Maintain the
Irrigation
System
Install a dedicated meter for the irrigation
system to measure the amount of water applied
to your landscape. Require regular maintenance
and request that staff managing the system
record trends in irrigation water use as part of
the maintenance program.
Obtaining records of outdoor water use trends can
help identify opportunities for additional water and
cost savings or common places or activities that
contribute to water waste. Some water utilities offer
an interruptible rate for the service or will not apply
sewer charges to water used for irrigation.
Water Savings
How much water your property can save outdoors depends on where you are, what you
plant, and how well your irrigation system is designed and maintained. But various studies
have reported savings ranging from 18 to 50 percent from converting landscape plants with
high water requirements to those with lower water requirements. A more water-efficient
landscape can also provide ancillary benefits and cost savings by reducing the need for
maintenance, fertilizer application, and fuel use.
An irrigation system's water use is the primary input to determine your landscape's potential
water savings. As discussed previously in the Understanding Outdoor Water Use section,
there are several approaches to estimate your landscape's annual irrigation water use. To
estimate water savings resulting from replacing or retrofitting irrigation systems with more
water-efficient components, insert your property's estimated annual irrigation water use into
the equations presented on page 11.
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Irrigation Controllers
EPA estimates that replacing a standard clock timer with a WaterSense labeled controller
can reduce irrigation water use by 15 percent.5 To estimate water savings from installing a
WaterSense labeled controller in your system, use Equation 1.
Equation 1. Water Savings From Irrigation Controller Replacement
(gallons per year)

X
15%
—

Annual Irrigation Percent Savings Gallons Saved
Water Use in	per Year
Gallons
Spray Sprinkler Bodies
Replacing sprinkler bodies in an irrigation system operating at or above 60 psi with
WaterSense labeled spray sprinkler bodies can save a property more than 20 percent of
irrigation water use. Even irrigation systems operating at lower pressures can achieve some
water savings by replacing existing spray sprinkler bodies without pressure regulation with
WaterSense labeled models.
To estimate water savings from replacing spray sprinkler bodies, use Equation 2.
Equation 2. Water Savings From Spray Sprinkler Body Replacement
(gallons per year)
x
Annual Irrigation Percent Savings Gallons Saved
Water Use in	by System	per Year
Gallons	Pressure
Based on your irrigation system's operating pressure, use Table 4 on page 12 to determine
the percent savings associated with replacing existing spray sprinklers with or installing new
WaterSense labeled spray sprinkler bodies.6 If you do not know your system pressure,
work with your irrigation professional to take this measurement at the sprinkler heads
closest to and furthest away from the irrigation valve.
5	EPA's WaterSense program. WaterSense Specification for Weather-Based Irrigation Controllers Supporting Statement. Version 1.0. November 3, 2011
6	EPA's WaterSense program. WaterSense Specification for Spray Sprinkler Bodies Supporting Statement. Version 1.0. September 21, 2017.	
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Table 4. System Pressure and Expected Associated Water Savings
System Pressure (Psi)
Percent Expected Water Savings
<30
0
31 to 39
5
40 to 59
16
60 to 69
23
>70
24
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Additional Resources
Alliance for Water Efficiency. Resource Library. Landscape, Irrigation, and Outdoor Water
Use.
www.allianceforwaterefficiencv.org/Landscape and Irrigation Library Content Listing.aspx
Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE)
Federal Energy Management Program (FEMP). Best Management Practice #4: Water-
Efficient Landscaping.
https://energy.gov/eere/femp/best-management-practice-4-water-efficient-landscaping
DOE EERE FEMP. Best Management Practice #5: Water-Efficient Irrigation.
https://energy.gov/eere/femp/best-management-practice-5-water-efficient-irrigation
EPA. Green Infrastructure Web Page.
www.epa.gov/green-infrastructure
EPA's WaterSense Program Resources:
Irrigation Controllers
www.epa.gov/watersense/irrigation-controllers
Irrigation With a Pro
www.epa.gov/watersense/irrigation-pro
Outdoors
www.epa.gov/watersense/outdoors
Soil Moisture-Based Control Technologies
www.epa.gov/watersense/soil-moisture-based-control-technologies
Spray Sprinkler Bodies
www.epa.gov/watersense/sprav-sprinkler-bodies
The WaterSense Water Budget Tool
www, e pa. go v/wate rse n se/wate r- bu dg et-too I
WaterSense at Work. Best Management Practices for Commercial and Institutional
Facilities. October 2012.
www.epa.gov/watersense/best-management-practices
Irrigation Association (IA). Landscape Irrigation Best Management Practices. May 2014.
www.irrigation.org/IA/Advocacv/Standards-Best-Practices/Landscape-lrrigation-
BMPs/IA/Advocacv/Landscape-lrrigation-BMPs.aspx?hkev=93b546ad-c87a-41b8-bf70-
8c4fd2cff931
The Sustainable Sites Initiative (SITES®).
www.sustainablesites.org/
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Landscaping and Irrigation
*
Water Sense
Appendix AiSummary of Water Efficiency Measures and Savings
This appendix can be used to summarize water efficiency measures, upgrades, and
projects that are identified at your property, based on a water assessment and/or review of
this Water Efficiency Management Guide.
Summary of Water Efficiency Measures and Savings
Item
Number
Location
Measure or Project
Name and Description
Projected
Annual
Water
Savings
(gallons)
Projected Annual
Water, Wastewater,
and Energy Cost
Savings ($)
Total
Measure
or Project
Cost ($)
Simple Project Payback
(years)
Example
Landscape
irrigation
system for
all zones
Replace existing clock
timer irrigation controller
with a WaterSense
labeled irrigation
controller. New
controller costs $200
and a certified irrigation
professional will install
and program it for $400.
210,000
gallons
Water Cost Savings:
$1,020
$600
(purchase
and
installation)
0.6 years
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