An irrigation audit is the method of inspecting and measuring how effective the sprinklers are working together to apply the water within each individual irrigation zone or test area. Results are compiled and used in combination with irrigation needs of the site being audited to facilitate an irrigation water management plan.
An irrigation Audit will pinpoint any issue in need of immediate attention and indicate where system improvements should be made to conserve water and protect your landscape.
Inventory sprinkler system’s water meter, backflow preventer, controller and head count. A site landscape inventory is also produced. Water pressure is measured and any other site specific conditions such as soil type and slope are noted.
Sprinkler application devices, including pop-up spray heads, rotors, micro sprays and bubblers are designed to operate within specific operating pressures and head spacing. Manufacturer’s specification catalogs rate the performance (mainly flow rate) in gallons per minute and precipitation rate in inches per hour. Commonly, the rated performance listed in the catalogs do not accurately represent actual performance. For example, insufficient or excessive operating pressure and improper head spacing will significantly increase or decrease precipitation rate.
For irrigation scheduling purposes, the most accurate determination of precipitation rate is achieved by conducting a “catch can” test. Catch can tests measure the amount of water that hits the ground at various points within the landscape, and serves to measure application uniformity. Since irrigation systems commonly use different types and brands of sprinklers, it is important to conduct catch can tests for each individual zone or “station” on an irrigation system. Once this test is performed the precipitation rate can be calculated into inches of water per hour.
The system inventory will indicate the overall condition of your sprinkler system.
The landscape inventory tells us how many inches of precipitation per zone is needed.
The performance test determines how long and how often to irrigate.