Is your irrigation system up to code?

From the University of Minnesota Turfgrass Science Newsletter

If you have an irrigation system, late spring is a great time to ensure it is working properly and up to code. In Minnesota, all automated irrigation systems are required to have a bypass moisture sensor installed. The moisture sensors could be a rainfall sensor or a soil moisture sensor, but both work similarly. A moisture sensor is designed to detect recent rainfall events and will instruct the irrigation system to bypass or skip the next scheduled watering.

It is remarkably easy to test to ensure your moisture sensor is installed correctly and working properly. First, schedule your system to run in 20-30 minutes. After locating your moisture sensor, pour a few ounces of water over the sensor prior to when you have your system scheduled to run. If the sensor is working, the system will not run as scheduled. Depending on the model of the irrigation controller, there will likely be an indicator on the controller that the moisture sensor detected “rain” and bypassed that scheduled irrigation timing.

If the moisture sensor failed at delaying the irrigation system from running, or if you know you need a new moisture sensor, consider contacting your local municipality. Many cities in Minnesota have a rebate to offset the cost of a new moisture sensor and/or the cost of a smart irrigation controller. Regardless, most cork-type rainfall sensors are relatively inexpensive, are compatible with most irrigation controllers, and will pay for themselves within the first year through water savings. A functioning moisture sensor not only saves water, but it also helps from over-watering your lawn.

Sec. 103G.298 MN Statutes Landscape Irrigation Systems | Minnesota Legislature

Auditing home lawn irrigation systems | UMN Extension

Water-saving strategies for home lawns | UMN Extension

Help with lawn water conservation | UMN Turfgrass Science