Farmers need to make sure irrigation equipment is completely drained to prevent freezing damage when winter temperatures set in.
Howard Neibling, extension irrigation water management engineer for the University of Idaho, explained if water is left in mainlines and wheel lines, it can freeze and break the line.
“Next year when you are trying to run water, and you need to move a lot of water in a hurry, all of a sudden you have mud hole there and you’ve got to shut the system down for several days,” Neibling said.
He said low spots that won’t drain are usually the first to freeze. If a pipe has a low spot, Neibling suggested connecting a riser or anything the water can be pumped out through using a portable pump.
Centrifugal pumps, used to pump water from canals to irrigation lines, also need to have all the water drained from them.
“You don’t want it freezing because freezing water will break a nice cast iron housing on a pump,” Neibling said. “It will just split it wide open.”
Fall is also a good time to inspect hoses that connect mainline to wheel line outlets, according to Neibling.
“It’s a time to look your equipment over and see what could go wrong or cause you problems later in the spring and summer. Anything you can fix should be fixed in the fall,” he said. “The spring gets so crazy — you’re trying to do so many things — you don’t have time to deal with any of these maintenance issues.”
He said worn hoses and worn nozzles, or nozzles that are the wrong size, should be replaced.
“When it’s still working, make a note of what gaskets are leaking and replace those once fall is here,” he said.
According to Neibling, results from testing dozens of wheel lines revealed the average water loss from leaks was about 12 to 14 percent of total system capacity. Worn nozzles or wrong-size nozzles added 12 to 14 percent loss to that.
“That’s 25 percent loss in water just due to those items,” he said.
Equipment owners should also inspect pivots for worn bearing seals and joints that need to be greased. Ensuring joints are greased and seals are secure will help keep water out of the joints, Neibling said.
Oil in center pivots gearboxes needs to be checked and filled to proper levels at the end of the season. Neibling recommends using the oil recommended by pivot manufacturers.
He said pivot tires that look low should be filled or repaired right away.
“You don’t want a flat tire in the hottest part of the season next year,” he said.
Wheel line engines need pre-winter care, too. They can be removed or left on the line. Fuel should be emptied by running the engine until all the fuel runs out, or by siphoning the tank. The oil and the air filter should be replaced if necessary. The engine and other mechanical parts should be covered until the threat of extreme cold and moisture has passed.