WaterSense Labeled Irrigation Products
Oklahoma Makes Median Irrigation OK
City Strips Inefficient Sprinkler Systems of Water Waste
look for
Project Summary
The Oklahoma City Utilities Department partnered with a local nonprofit and a landscaping company to retrofit
three highly visible median irrigation systems. By using a WaterSense® labeled irrigation controller and
sprinkler bodies that meet WaterSense criteria, the project reduced water use, improved irrigation distribution
uniformity, and decreased runoff in a unique landscape area.
Background
Medians calm traffic and beautify urban streets and highways. In
areas with variable rainfall, medians may use turfgrass or other
landscaping that requires regular irrigation. Proper irrigation
system design and maintenance are important, because medians
are much narrower than typical landscapes, and sprinklers are
more exposed to potential damage from cars and pedestrians.
In Oklahoma City, Oklahoma, the local utilities department often
received calls about median sprinkler systems that were
overwatering, wasting water, and causing runoff in the street. This
didn't reflect well on the city or the organizations that sponsor
maintenance along the roadway. The Oklahoma City Utilities
Department partnered with a local nonprofit organization and Keep
America Beautiful affiliate, OKC Beautiful, to sponsor a pilot
project to determine ways to improve irrigation, starting with three
median strips. They also partnered with a local landscaper, Urban
Lawn and Landscape, to provide installation services.
Evaluating the Problem
To get to the root of the water waste, the three median strips were tested to
determine the water pressure going to their sprinkler systems. Optimum
pressure for most sprinkler systems is about 30 psi, but the medians'
sprinklers were operating at 60 psi. High incoming water pressure can
prevent sprinklers from working as intended, causing misting, overspray,
puddles, and runoff (see photo at right). However, the U.S. Environmental
Protection Agency's WaterSense program developed criteria for sprinkler
bodies with integral pressure regulation to earn the WaterSense label, which
means they are independently certified for water efficiency and performance.
WaterSense labeled spray sprinkler bodies reduce the effects of high
incoming water pressure to prevent misting and overspray.
Case Study Highlights
•	Property: Three separate roadway
medians across the city
•	Location: Oklahoma City,
Oklahoma
•	Landscape size: Each median was
7,600 to 34,000 square feet, for a
total of 53,742 square feet of land
•	Water savings: The retrofit project
reduced water use in those median
strips by 67 percent (1.2 million
gallons of water saved between
2016 and 2019)
•	Cost savings: More than $5,000
annually
PHONE (866) WTR-SENS (987-7367) WEBSIiEwww.epa.gov/watersense EMAiLwatersense@epa.gov	°°

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Oklahoma Makes Median Irrigation OK
What's more, sprinkler heads on medians can be easily damaged; replacing
old or broken sprinkler bodies with water-efficient models can save water and
money. The medians that Oklahoma City Utilities selected also had major
water waste associated with leaks, broken sprinklers, sprinklers pointed in
the wrong direction, and overspray from sprinklers directed beyond the
median landscape, causing flooding in the street.
Because irrigation needs vary from year to year, Oklahoma City Utilities
developed a water budget for each of the three median strips, a target
against which water savings could be measured. Water budgets are based
on the irrigated area, plant type, and local weather. Before efficient sprinklers
were installed, the medians were regularly using between 60 and 70 percent
more water than was allotted in the budget.
Partners Made Pilot Possible
A key component of the successful pilot was the partnerships Oklahoma City Utilities established from the
outset. The mission of OKC Beautiful is to enhance the appearance of Oklahoma City through education,
programs, and community engagement. By leveraging their Landscapes Beautification Program, the city
created a demonstration of potential water savings for existing and new irrigation systems.
Urban Lawn and Landscape, which maintains many of the medians for OKC Beautiful, provided labor and the
technical expertise to install water-efficient sprinklers on the three pilot medians, which demonstrated the
local impact and potential water savings associated with these products. To assist with installation during the
pilot, Oklahoma City Utilities provided staff to direct traffic away from the median strips and keep workers
safe.
Water pressure can be tested at the
valve or the sprinkler head.
WaterSense partners Hunter Industries, Rain Bird Corporation, and the Toro Company provided products to
demonstrate their water-efficient equipment on each of the three medians. Although the project was
completed prior to release of the final WaterSense specification for spray sprinkler bodies, according to
Malarie Gotcher of the Oklahoma City Utilities Department, the installed models meet WaterSense criteria.
Strip by Strip Savings
Medians 1 and 2 are similar in design: Median 1 is
approximately 7,600 square feet and six irrigation zones of
tall fescue grass, trees, and shrubs; Median 2 has nine
irrigation zones covering more than 11,000 square feet. After
replacing the old sprinklers with sprinkler bodies with integral
pressure regulation, along with new nozzles, Gotcher said,
pressure tests found all the sprinklers consistently operating
at the intended pressure of 30 psi. This meant less misting
and water lost to the wind or streams of water flowing to the street. Gotcher also reported that the number of
calls about water waste at those medians decreased.
Did You Know?
Replacing all spray sprinkler bodies
across the country that operate above
optimal pressure with WaterSense labeled
models could save more than 31 billion
gallons of water nationally each year!
Median 3 is more unique; it covers an area of 34,525 square feet and is split between a median and a turning
lane. Along the length of the entrance lane, the median narrows to allow vehicles to merge, and this irregular
shape caused incorrectly positioned sprinklers operating at high pressure to miss their target and spray into
the road. A certified landscape irrigation auditor conducted a pre- and post-project audit and determined that
sprinkler heads and positions weren't optimal for the space. The system operating pressure was also too
high, and there were several leaks. The irrigation zones were reconfigured for better efficiency, and some
rotating sprays were replaced with multi-stream, multi-trajectory nozzles (MSMT).

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Oklahoma Makes Median Irrigation OK
The Median 3 installation also replaced a traditional clock timer with a WaterSense labeled weather-based
irrigation controller. WaterSense labeled controllers use local weather and landscape conditions to make sure
the system waters only when needed.
Results
Overall, the project has decreased water use on all three median strips by 67 percent compared to pre-
installation rates; an average 1.2 million fewer gallons of water than what was used in 2015. On Median 3
alone, water use was reduced from 1.4 million gallons in 2016 to 657,000 gallons in 2018. Medians 1 and 2
are now operating much closer to their water budget, with current savings estimated at 21 gallons per square
foot.
Lessons Learned
By starting with a limited number of medians, the Oklahoma City Utilities Department was able to identify and
address important issues that will be applied to future median irrigation systems. Following are some of the
lessons learned from the project that other municipalities may want to consider for median strip improvement:
•	Medians are unique. Due to their location, medians present unique challenges in terms of
conducting work and maintaining the system. Sprinkler heads located near turning lanes are more
likely to be damaged by vehicles.
•	Get a grip on the strip. Gotcher said the pressure testing on Medians 1 and 2 was helpful, but the
audit conducted on Median 3 was the most useful piece of the puzzle. In the future, they plan to
include a pre- and post-irrigation audit for other projects.
•	Put good boots on the ground. The Oklahoma City Utilities Department's project worked in part
because they identified partners who were stakeholders in keeping the city beautiful and competent
contractors to handle the installation.
•	Don't get caught in traffic. Upgrades were scheduled to avoid rush hour. With little room for
contractors to maneuver, the department had to close road lanes and direct traffic away from the
workers for their safety. Gotcher also noted that they needed to be flexible when scheduling
upgrades, because "the weather can turn on you."
•	Keep a happy median. While initial improvement and water savings are great, Gotcher noted, long-
term maintenance is critical to the success of a project such as this, especially when medians are so
visible to the public.
Acknowledgements
The U.S. Environmental Protection Agency's WaterSense program would like to thank Malarie Gotcher, the
Water Conservation Manager for the City of Oklahoma City Utilities Department, for providing images and
information for this case study.
Learn More
For more information about how the Oklahoma City Utilities Department reduced water use on medians,
watch the WaterSense and Alliance for Water Efficiency webinar, "Efficient Irrigation Practices for Medians
and Park Strips," on-demand at https://voutu.be/xpQWCFppxiY.
To read other case studies on outdoor water use, visit https://www.epa.gov/watersense/case-studies. For
more information about WaterSense at Work, a best management practices guide for commercial and
institutional facilities, visit https://www.epa.gov/watersense/commercial.

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