This blog is about practical and useful gardening advice for California Gardeners.
- Author: Pamela M. Geisel
Published on: March 10, 2010
Most of our irrigation systems run very early in the morning while we are asleep and problems can go on undetected for months. Poorly adjusted sprinkler systems also account for significant wasted water. Sprinkler heads that are broken, leaking, tilted, spraying the wrong direction or clogged will apply water in ways that are non uniform and lead to run-off or over irrigation in some areas and under irrigation in others. The end result is that you tend to irrigate to the dry spots and waste water.
To inspect your system, just turn on the manual cycle of the clock or turn the sprinklers on at the valve and view spray patterns. If you want to know how uniform the system is and what the application rate is, just do what is known as a Can Test. Place about 12 straight sided and flat bottomed cans or coffee cups in a grid on the lawn between sprinkler heads. Run your system for exactly 15 minutes. Measure, using a ruler, the amount of water accumulated in each can and record. If you multiply the average amount by 4, that will provide average inches per hour, also known as your application rate. If some cans have 1/2 inch of water and others with much less or much more, then your system is not very uniform. That leads to over irrigation and wasted water. Depending upon the severity of the problem, it may mean just cleaning the nozzles or replacing the heads.
For more details on using a Can Test to evaluate your irrigation system, go to our Free publication: Lawn Watering Guide for California