By Carmelita Nelson, Minnesota DNR Water Conservation Consultant
Somewhere in Minnesota, the county sheriff or the Department of Natural Resources (DNR) is getting a complaint about irrigation systems shooting water onto the roadway. Sending water through your center pivot’s end gun onto public roads can create hazardous driving conditions for cars and motorcycles and can be a major liability issue. Minnesota State Statute 160.2715 states that obstructing a highway or any detrimental operation within the road right-of-way is a misdemeanor. Wasting water by shooting it onto roadways also reflects poorly on farmers and can lead to public anger and resentment.
Sometimes the shut off devices will fail and this should be fixed as soon as possible to keep water off the roadway. More commonly, according to Steve Melvin, Extension Educator Irrigated Cropping Systems, the overspray is caused by incorrectly setting when the end gun turns off. To prevent spraying the road, the end gun must be turned off well before it approaches the road, even on a windy day.
Do you have an end gun on your irrigation pivot? End guns are an optional piece of equipment placed at the very end of the center pivots that can deliver water up to 120 feet beyond the end of the equipment. They can be turned on when the pivots go by the corners and provide water for an extra eight to 10 acres on a 160-acre field. While this seems like an economical practice, there can be downsides. End guns are the most inefficient part of the pivot, because it does not apply water very uniformly. The large droplet size can displace soil particles or, conversely, cause soil compaction. End gun systems also have high energy requirements. Older models of end guns are especially prone to malfunction and require ongoing maintenance.
As the irrigation season continues and there is more wear and tear on the equipment, farmers are encouraged to take time to make sure your center pivot’s end gun shutoff controls are working properly. There are two items you can inspect to make sure the water is going where it is needed: the end gun valve at the end of the machine and the angle position settings at the center pivot control panel. Often malfunctioning control valves result in the end guns not shutting off properly and allowing the water to flow to unwanted areas including onto roadways.
By having properly functioning end gun shut off controls, farmers can save a significant amount of water and associated pumping costs. Neighbors and passers-by will also be grateful for the precision use of our precious water resources.