October 2012
5-13
5.3
Irrigation
WaterSense has evaluated a number of studies conducted by a variety of organiza-
tions that cover numerous WBIC brands. Results from these studies indicate a range
of overall savings from 6 to 30 percent. Individual site savings can vary beyond these
overall numbers, depending upon the watering habits prior to installing the WBIC.
In some cases, site water use can increase if the facility was practicing deficit irriga-
tion before installing a WBIC. In a 2009 comprehensive study, first-year savings were
shown to be approximately 6 percent.
29
For a limited subset of controllers in this
study that were tracked for three years, overall savings were shown to be 16 percent
in the third year after installation. In full consideration of the findings of these numer-
ous studies, WaterSense anticipates seeing overall water savings of approximately
15
percent after proper installation of WBICs, when compared to systems that use a
clock timer with manual programming.
30
The key to saving irrigation water is to combine efficient irrigation practices with
efficient technologies. Additional details on many of these principles, practices, and
technologies can be found in the Irrigation Association’s (IA’s) Landscape Irrigation
Scheduling andWater Management and Turf and Landscape Best Management Prac-
tices
31
documents.
Operation, Maintenance, and User Education
There are several best practices a facility can consider to optimize an irrigation sys-
tem’s efficiency, such as ensuring irrigation professionals are properly educated on
water-efficient practices and that existing irrigation systems are properly operated
and maintained.
Irrigation Professional Education
Consider the following to ensure irrigation professionals have a strong understand-
ing of the principles of water-efficient irrigation:
••
Ensure existing professionals or staff managing the irrigation system become
familiar with water-efficient irrigation practices through partnerships, classes,
seminars, and/or published guidance documents. Encourage professionals or
staff managing the system to:
à
à
Become certified through a WaterSense labeled irrigation certification pro-
gram with an emphasis on water efficiency.
32
à
à
Consult the local water utility, community colleges, or agricultural services
for courses or seminars on water-efficient irrigation practices.
à
à
Review technical guidance documents provided by local cooperative exten-
sion services and irrigation trade associations.
29
Mayer, Peter, et al. The Metropolitan Water District of Southern California and the East Bay Municipal Utility District. July 1, 2009.
Evaluation of California Weather-
Based “Smart” Irrigation Controller Programs
.
30
EPA’s WaterSense program. November 3, 2011.
WaterSense Specification for Weather-Based Irrigation Controllers Supporting Statement
.
Page 12.
31
IA. Best Practices & Standards: Turf & Landscape Irrigation Best Management Practices.
.
32
EPA’s WaterSense program. Professional Certification Program.
.
