Irrigation Systems Purchase Tips

So you want to install an irrigation system? There are a few things you should know in advance.

First, your water bills will likely go up. Recent studies of homes with and without automatic sprinkler systems show that homes with automatic systems use substantially more water outdoors on average (Maddaus and Mayer, 2001). Automatic irrigation systems, if not properly managed, can waste a lot of water. Always be mindful that YOU are the "brains" behind your irrigation system scheduling and YOU control the controller.

Think about your entire landscape plan when considering an irrigation system. Are you going to re-landscape or add Xeriscape beds in the near future? Make sure your sprinkler system is adaptable to your future landscape plans.

There are lots of irrigation and sprinkler system designers and installers out there. If you are going to hire someone to design and install your system, get several bids. Prices can vary a lot from company to company. Be sure you understand the differences between the bids. The low bid may not provide you with the best irrigation system for your landscape.

Drip irrigation techniques have improved in the past ten years. A well designed drip system should use less water than spray emitters. Some installers may not be familiar with the newer more advanced drip systems. Shop around to make sure you’re getting the most for your money.

Include some type of automatic shutoff device with your sprinkler system. These devices will help you maximize water efficiency and improve the effectiveness of your system. They include:

  • Rain sensors – these stop irrigation when it’s raining
  • Wind sensors – these stop irrigation when it is too windy for good coverage
  • Soil moisture sensors – these control irrigation based on the moisture level in the root zone of plants.
  • Humidity sensors – these devices control irrigation based on the relative humidity

Selecting an Irrigation Controller

The key to watering efficiently is to obtain a controller that can handle diverse landscape and weather situations and then to program it properly to meet your plants’ water needs.

The recommended minimum hardware features for a controller when water efficiency is a priority include:

  • Three independent programs
  • Station run times from one to 200 minutes
  • Three start times per program
  • Odd/even, weekly, and interval program capability up to 30 days
  • Water budgeting from 0-200%, in 10% increments, by program
  • 365 day calendar, adjusted for leap year
  • Non-volatile memory or battery back-up
  • “Off”, “Auto”, and “Manual” operation modes without disturbing programming
  • Rain/weather shut-off device capability
  • Diagnostic circuitry to notify you when station is shorted or a power failure has occurred

These features are important because they give you the ability to properly manage your landscape watering.

Other Important Components to Consider

Here are some other irrigation system components to consider for maximum efficiency:

  • Control valves – control the flow of water to different parts of the landscape and are used for the separate watering of plants with different watering needs.
  • Check valves – can be installed in sprinkler heads to prevent water form draining out of the irrigation line when the water is turned off and are most useful on sloped landscapes.
  • Rain shutoff devices and moisture sensors – (see above)
  • Drip or bubbler irrigation – can be used to irrigate slowly and minimize or eliminate evaporation, runoff, and overspray.
  • Low precipitation spray, stream, and sprinkler heads with matching precipitation rates can dramatically improve efficiency.

There are several new irrigation controllers that utilize information on temperature and precipitation to manage irrigation. To learn more about this cutting edge technology that has the potential to dramatically improve irrigation efficiency, check out the Future Trends in irrigation page.

Sources:
"Irrigation Controllers for the Homeowner", brochure.