From a Technical Perspective

By Larry Peach

Improving Irrigation System Efficiency

With power rates on the increase, there are several places you can look to improve the efficiency of your sprinkler system. Leaks in the mainline and distribution system are common to all sprinkler systems. Many producers aren’t too concerned about leaks in the field because water is ending up in the field anyway. Leaks reduce the systems operating pressure, causing a poor distribution pattern. Reduced pressure can change the operating efficiency and increase demand cost.

Worn nozzles and mismatched nozzles, like leaks, are the most common and underrated problems with sprinkler irrigation systems, and a primary cause of increase of power demand cost. Just a tiny bit of nozzle wear can cause a big increase in sprinkler output and can decrease the systems application efficiency. To check for nozzle wear insert the shank end of a new drill bit the same size as the size that is printed on the nozzle into the nozzle. If you can wobble the bit sideways even slightly, the nozzle is worn and should be replaced.

Pumps will lose efficiency from wear over years of use. Rebuilding your older pump to increase its efficiency can be a cost effective alternative to purchasing a new one. For optimum efficiency, the pump must match the requirements of the delivery system and irrigation equipment. If your pump is under or over sized, replacement is the best option. Running an oversized pump with a mainline valve half closed is like driving your car with your foot on the brake and the accelerator at the same time.

If you are installing a new motor, an 1800 RPM motor is more efficient than a 3600 RPM motor, and usually has a longer life. Also, consider a premium efficiency motor instead of a standard efficiency motor in a new installation. Premium efficiency motors are more power efficient and have a longer service life than standard efficiency motors.

If you are interested in having an efficiency test preformed on your pumps, at no charge, or interested in the free nozzle exchange program, contact T.J. Woodley at the Tulelake NRCS office 503-667-4247.