Reviewed and Revised on 10/17/2013
As much as one half of all the water used by the average homeowner goes to lawn irrigation. If you have a typical 5,000 square-foot yard and use an in-ground sprinkler system, you may be spending $2.50 to $6 every time you water. Costs may vary in communities across the US. Over watering the lawn and landscape is the most common error many homeowners make; this is much more common than applying too little water. Keep in mind that most cities you are charged twice for water: once for fresh water coming in and a second time for the estimated waste water that you discharge.
Using less water means less energy gets consumed in providing that water to you as the fresh water in the first place. The thing to be considered even before having an energy efficient home irrigation system is to have climate appropriate plants and trees which require less water and are drought tolerant. These will reduce the amount of water needed for the irrigation. You can contact your local Cooperative Extension Service to find out if they have information about landscaping for water efficiency. You can also read Landscaping Your Home for Energy Efficiency for more information.
How can I save water and money, yet still have an irrigation system?
This can be accomplished in following ways.
Check to see if there is an operating rain sensor or soil moisture sensor device on the irrigation system. These devices can ensure the landscape is watered only when needed.
Design the irrigation system so that zones for turf are separate from other landscape plants. In general, turf needs more water than established shrubs and trees. Therefore, if you have the same irrigation zone for both, you could water the turf correctly while flooding the shrubs and trees. In fact, once established, most shrubs and trees don’t require additional irrigation unless there is a drought.
- Turn on all irrigation zones to check for leaks and to see that all irrigation heads are operating.
- Adjust irrigation zones to avoid sprinkling buildings, driveways, streets, and sidewalks. In addition, be certain that plants or structures do not interfere with irrigation spray patterns.
- Dual programmable timers allow you to irrigate different areas of the landscape for different lengths of time.
- Multi-zone irrigation systems allow you to water only those areas that need it.
- Look for micro-irrigation systems (sometimes called low-volume irrigation), which use water efficiently and dispense water slowly near the base of the plant, thereby reducing runoff and evaporation.
- Check on the availability and legality of reclaimed waste water, cistern water (from rainwater harvesting), or grey water for irrigation.
- Whether buying an existing home or a new home, avoid the six most common irrigation related errors:
- Broken or misdirected sprinklers
- Plant parts or grass blades interfering with the sprinklers; these branches, trunks, or leaves cause the spray pattern to be uneven.
- Mixed sprinklers—for instance, having sprayers and rotors in the same zone. When stationary shrub sprayers and rotating turf sprinklers are used in the same irrigation zone, the shrubs usually end up being overwatered.
- Unmatched precipitation rates. The flow rate of a sprinkler covering 90 degrees should be half the amount of the same type of sprinkler covering 180 degrees.
- Improperly spaced sprinklers. Space the lawn sprinklers so the water from one head almost touches, even overlaps, the other surrounding sprinkler heads thereby ensuring full coverage.
- Incorrect scheduling. Irrigation controllers are often set to run too frequently or too long per irrigation. Consequently, lawngrass and landscape plants are over-irrigated, water is wasted, fertilizers are washed away, and diseases are promoted. Water only as needed.
- Call your water utility company, a local irrigation contractor, or your local Natural Resources Conversation Service to see if they can provide an irrigation system evaluation through the Mobile Irrigation Laboratory or some other method.