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How to Save Money and Avoid a Breakdown

Maintenance is the key to an efficient irrigation system.

By Amanda Huber

The year 2000 was the most expensive peanut crop in history. Part of that expense came from the tremendous amount of irrigation needed to make the crop. After having to irrigate so much, your system will need some attention before it is time to irrigate again.

The goal of an irrigation system is to apply the desired amount of water uniformly and efficiently, but the key to achieving that goal is maintenance. Worn parts, leaky seals and loose connections reduce efficiency and are an invitation for breakdown. Of course, Murphy’s Law dictates that a breakdown will occur at the most critical time for water use, pegging and pod fill.

Avoid losing critical yield by inspecting your system using the provided checklist. A leaky seal here and a damaged sprinkler there adds up to inefficiency and costs you money. Replace all leaky, clogged or damaged parts.

Do not just stop with a visual inspection, however. Be sure to crank up the motor and run the system while you walk along and listen for unusual sounds. You may detect a problem that you cannot see.

Your final inspection should be in your filing cabinet. Review information and warranties, and make sure you understand the terms and conditions. Again, this will save critical time if a breakdown occurs.

You may still have a breakdown, but time spent inspecting your system now will reduce the chances of this happening during the year. It will also help extend the life of your system, saving you time and money.

Maintain your irrigation system using this checklist, checking those things that apply.

What to look for:
- Grounding conductors cleaned and tightened

- Anchor chains and grounding conductor hook-ups clear and properly adjusted

- Screens on generators, pump panels and electric motors in place and damage free

- Motor lead properly connected

- Tires inflated to proper pressure

- Lubricants filled to proper levels

- Gear motor and gear box seals not leaking

- Drive shaft bearings and U-joint in good condition; covers in place

Start the system and see that:
- Nozzles are clear and producing a good spray pattern

- Impact sprinklers are rotating properly

- Drive unit is working properly

Four Steps to Maintaining Your Sprinkler Package

Sprinkler package maintenance is an important part of the overall servicing of your center pivot irrigation systems. Keep your sprinkler package operating at peak performance by following these four steps:

1 - Update your sprinkler chart to reflect your current system. Check the pipe diameter of each span, the total system length, tire sizes, center drive motor rpm, spray nozzle drops and, if applicable, end gun and other miscellaneous equipment. If your chart is no longer current, a new chart should be developed. Your updated system may require new sprinkler nozzles.

2 - Test your well to be sure it is producing the same gallons per minute as when the sprinkler chart was developed. Sand, the water table rise or fall and changing groundwater recharge rates can reduce your well’s effectiveness.

3 - Use a pressure gauge to test water pressure at the pivot and compare to that specified in the sprinkler chart. A second pressure gauge at the end of the system should give the same reading. As a general rule, a change in water pressure of 1 psi from that specified in the sprinkler chart will change the application depth by 2 percent.

4 - Visually check for worn or broken sprinklers and nozzle parts and for a uniform spray pattern. Randomly check flow of nozzles and pressure of regulators, and compare to sprinkler chart. Replace nozzles if the flow varies more than 5 percent to 10 percent, and replace pressure regulators if the pressure varies more than 10 percent to 20 percent.

Compiled from information provided by Kerry Harrison, UGA Extension engineer, and CMF&Z agency for Valmont Irrigation.