Sprinkler Performance

Print
Share & Bookmark, Press Enter to show all options, press Tab go to next option

 As much as 50 percent of the water we use outdoors is wasted from inefficient watering methods and systemsEliminate Water Waste


The City of Bend Utility Department is actively working to reduce the amount of water wasted through inefficient irrigation practices throughout our community. Doing so helps stretch water supplies further into the future, keeps the watershed healthy and helps to keep sidewalks and streets safe for bicyclists and pedestrians. The City of Bend has Water Waste code (Bend Code 14.20 Use of Water) that outlines what is considered an inefficient or wasteful use of water.


SPRINKLER PRESSURE

Higher operating pressures increase the flow of water going through the sprinklers and when too high, can cause misting of water, leading to increased overspray and runoff through drift. The left image below is under too-high pressure (photo courtesy of Irrigation Association). The right photo below shows correct pressure (photo courtesy of Rainbird).

misting sprinklers wasting water

Ideal operating pressures for sprinkler types:

  • Fixed spray 20 - 30psi
  • Rotor 30 - 60psi
  • Drip 20 - 40psi

Water-Efficient Spray Sprinkler Bodies 

Pressure regulating sprinkler bodies replace a standard sprinkler body to maintain constant pressure, producing even delivery throughout the irrigation system. They are available for pop up spray and rotor type sprinklers. Each sprinkler on a zone must be replaced to be effective. Link to WaterSense sprinkler body fact sheet.

Pressure Regulating Dials 

A pressure regulating dial attaches to an existing valves solenoid and allows adjustment of pressure for all the sprinklers on an individual zone without cutting into pipe.

pressure regulating dial adjusted by hand

SPRINKLER ADJUSTMENT

Check sprinklers for alignment and adjust each so that only planting areas receive water.

adjusting sprinkler heads

water on sidewalk from sprinkler overspray

 

SPRINKLER UNIFORMITY

Sprinkler uniformity refers to how evenly our sprinklers distribute water over our landscapes. Uniformity is a reflection of the operational status of our sprinkler system and has a direct effect on our water use. Systems with bad uniformity typically use more water than necessary and are wasteful. Conversely, a system with good uniformity applies water evenly to all intended areas without runoff or increased run-times.

 poorly set tilted, low and blocked sprinklers

Tilted sprinklers, low sprinklers or sprinklers blocked by maturing plants  cannot distribute water evenly due to the interference of their spray pattern. (See images above, left to right.) These are all causes of dry spots during summer months and can lead to run-times being increases. Sprinklers can easily be raised, straightened or rerouted to be free of obstructions. See moving a sprinkler on the Leaks and Breaks page.

Not a Good Mix

In general, 10 minutes of a fixed spray sprinkler will deliver the same amount of water it would take a rotary sprinkler to deliver in 30 minutes. Mixing sprinkler types will lower sprinkler uniformity and cause excessively wet or dry spots within the landscape. More information is available in our Streetscape Irrigation flyer.

Mixing sprinkler types can create puddling and dry spots

Properly Match Precipitation Rates with Rotor Nozzles

Contrary to our intuition, matching nozzles in our rotor sprinklers does not mean installing the same nozzle in each rotor.  Each Rotor needs a different nozzle depending on the pattern of the sprinkler in order to apply water evenly. See the pic. below to learn how to match nozzles.

The To match precipitation rates you must match a flow in GPM with the arc that the sprinkler will cover.

THE RIGHT PLANT IN THE RIGHT PLACE

Watering a lawn in the narrow confines and extreme environment of a street strip planter is difficult to do without creating overspray and runoff. In addition to the wasting water, overspray and runoff can facilitate the transport of pollutants into stormdrains and toward our underground drinking water supplies.

Step by Step instructions for converting your street strip planters to a WaterWise StreetScape are available in our Streetscape Guide.

Footer Broken Top Three Sisters