Page 168 - WaterSense at Work

October 2012
Rain, freeze, and wind sensors to interrupt irrigation during unfavorable
weather conditions.
Flow rate-monitoring equipment that can interrupt irrigation if excess flow is
Use alternative sources of water (see
Section 8: Onsite Alternative Water Sources
where environmentally appropriate and local regulations allow. Keep in mind
that while alternative sources are an additional way to save water in a landscape,
efficiency should come first. Apply all the principles above to build the optimal,
efficient system, and then consider using alternative sources.
Savings Potential
Irrigation water savings can be achieved through proper design, installation, and
maintenance, combined with efficient technologies. In addition, the landscape itself
e.g., plant palette, soil type, etc.) plays a role in irrigation water use and provides
potential for additional water savings (see
Section 5.2: Landscaping
for more details).
In order to consider irrigation system improvements and their associated savings, it
is important to first understand how much water is being applied to the landscape.
Dedicated irrigation meters track irrigation water use and allow facilities to docu-
ment actual savings.
The WaterSense Water Budget Tool,
developed by EPA to support residential land-
scapes associated with WaterSense labeled new homes, can be used to see how
relative water needs adjust by changing the plant palette and associated irrigation
type. For example, replacing a large turf area irrigated by spray heads with plant beds
irrigated by drip irrigation could significantly reduce water use. The Water Budget
Tool allows a landscape professional to alter the irrigation type in a virtual setting,
analyzing the relative water savings associated with each design change. The tool,
however, is not intended to estimate actual savings; it is meant to evaluate the rela-
tive water savings achieved with different palette and technology choices.
Savings from implementing any of these technologies are dependent upon the
system as a whole, including the landscape and climate, and, therefore, are land-
scape-specific. Following are a few examples of savings realized from implementing
water-efficient technologies in the landscape:
Installing drip irrigation uses 50 percent less water than conventional in-ground
sprinkler systems.
Water-efficient sprinkler technologies can reduce water use by as much as 30
percent when compared to standard pop-up sprinklers.
EPA’s WaterSense program. The WaterSense Water Budget Tool.
Gleick, Peter H.,
op. cit
Solomon, K.H., et al.,
op. cit