Bought an Irrigation System? Time to Audit!

Whether they’re motivated by environmental concerns or money, most people are interested in conserving water. Luckily, these two concerns go hand-in-hand; using less water protects our natural eco-systems from further resource depletion, ultimately reducing your water bill and decreasing the likelihood of getting busted by those pesky “water police” for using too much. These concerns are especially real to community managers of huge homeowners associations or commercial sites where millions of gallons of water are utilized each year. One of the main culprits, especially in Minnesota, is landscape irrigation. Fortunately, there’s a solution: a landscape irrigation audit.

Irrigation Association, defines a landscape irrigation audit as, “a procedure to collect and present information concerning the uniformity of application, precipitation rate, and general condition of an irrigation system and its components.” (IA Glossary of Terms) Okay, that’s a lot of industry jargon – let’s unpack. “Uniformity” refers to how evenly water is applied to the soil and is expressed as a decimal. Ideally, you want a high uniformity, as close to 1.00 as possible. “Precipitation rate” is the rate at which a sprinkler system applies water to a given area and is often measured in inches per hour. Both of these factors are important when calculating the efficiency of a landscape irrigation system.

It is important to note there are two different types of audits: Stage One and Stage Two. Although they share the same objective to save water when landscaping, there is a distinct difference. A Stage One landscape irrigation audit solely consists of a thorough visual system inspection. Each sprinkler zone is activated while a certified auditor observes all of the sprinkler heads to identify which are (or are not) working correctly. The auditor also ensures water is being applied to the landscape as intended by taking note of sprinkler spacing, system pressure, system controller information, water meter readings, and many other factors. Once a Stage One audit is complete, the auditor will report their findings and make a few general recommendations to the client.

Stage Two landscape irrigation audits are more calculation-focused. Remember uniformity and precipitation rate? This is where they come into play. In order to get both of these measurements, the auditor performs something called a “catch can” test. Catch cans are small containers spaced at regular intervals to collect water from sprinkler heads. In order to complete a catch can test, the auditor will pick a testing area on the landscape and place each catch can down onto the soil. Each sprinkler zone is turned on for a designated testing run time – the amount of time each sprinkler group is operated to allow collection of water – until  the entire test group has run. All sprinklers within the test area will be run the same amount of minutes or be adjusted to achieve the same precipitation rate to ensure accurate calculations.


After calculating the test area’s uniformity, average precipitation rate, and a few other factors, the auditor creates a report. This final step may seem simple, but it is crucial to the client. Not only will they report their calculations, but the auditor will also supply various recommendations for improvements – including an enhanced watering schedule. An appropriate irrigation schedule assures the correct amount of water is being applied at the right time of day, in addition to accommodating factors such as weather and plant needs. Other recommendations may include incorporating weather technology into the irrigation system such as a rain sensor or moisture sensor. The ultimate goal of the audit report is for the client to fully understand their current irrigation system and walk away with steps they can take to improve system efficiency – which ultimately saves water and money.

Long-term benefits of a Stage One or Stage Two landscape audit can be tremendous. An efficient irrigation system performance will enable the following:

  • Radically decrease water use and water bills
  • Improve landscape health and appearance
  • Reduce water runoff and aquatic pollution
  • Decrease dependence on fertilizers and chemicals
  • Protect a critical resource for the future


Do these benefits sound appealing to you? The first step of getting your own audit is research! Look for companies who employ Certified Landscape Irrigation Auditors, a certification through the Irrigation Association. Only an experienced and certified auditor will conduct a proper irrigation audit with proven results – if recommendations are followed through and properly managed. It doesn’t hurt to look for professionals who are also certified in other water conservation programs, such as the EPA WaterSense program. WaterSense certified irrigation professionals have met the EPA’s criteria for competency in a variety of topics including irrigation auditing. For more information on both of these programs, visit and

Water in Motion has experienced and certified staff members ready to help you with any landscape irrigation audit question or needs! Contact us and start your journey to a more water efficient irrigation system.