Many landscape professionals rely on irrigation systems to supplement the water for plants from rainfall. Around 67% of Utah’s municipal water supply is used for landscape irrigation alone. However, often too much water is applied during irrigation resulting in excess water consumption and money wasted.
An irrigation audit is a procedure that collects data to ensure that the irrigation system design works properly and identifies ways to improve water consumption. This includes analyzing water requirements and irrigation use in context to the site’s conditions, developing irrigation schedules based on water requirements, offering maintenance recommendations to help keep the irrigation system working effectively, and working to implement better irrigation technologies to reduce cost and water consumption for their landscape design.
Many clients ask for an audit when their bills get too high or they are required to cut their usage. An irrigation audit allows the client to compare ways of irrigation. An irrigation auditor may take a typical zone of sprinklers and do a catch-cup test to set a benchmark for the area. Then, they will raise, straighten, and respace the heads, and adjust the water pressure, then do another catch-cup test. That allows a before-and-after comparison and shows the client how much water and money can be saved.
More specifically, an irrigation auditor is looking to find the DU lq. DU lq means “distribution uniformity, lower quarters.” To find the DU lq, the auditor takes the total volume of water collected in the lowest 25 catch-cups and divides it by the total volume of water collected in all catch-cups. The lower the DU, the worse off the system is performing. A lower DU indicates that some areas receive substantially more water than others while trying to irrigate the driest areas. The purpose of calculating the DU lq is to select watering runtimes for the driest 25% of the area audited. In the best-case scenario, a water audit will show that the system has the highest uniformity possible. This means that the more catch-cups that are close to an average value, the more uniformity there is within the system. This indicates a well-functioning irrigation system.
One way to assist your irrigation auditor and to help maximize your water and cost savings is by keeping accurate and up-to-date records throughout the year. These records include water usage, rainfall, evapotranspiration rates, and high temperatures. It also helps to record information on the irrigation system such as number of irrigated acres, system improvements, head locations, spacing, operating pressure, controllers, the sprinkler make and model, and nozzle sizes.
Having an annual audit conducted and making the repairs to the defective irrigation units can improve make the greatest change in the system efficiency and water consumption of your irrigation system design.
Interested in making improvements to your irrigation system? Give us a call at (801) 567-2383 or click on our Contact an Expert green arrow on any page of our website to get in touch with one of our irrigation system design contractors today.
