Managing and Maintaining a Drip Irrigation System

Managing and Maintaining a Drip Irrigation System

Rick Gibson

Cooperative Extension Agent, Agriculture

Pinal County, ARizona

If you have a drip irrigation system, now is a good time to perform regular maintenance chores and make needed repairs.

The cooler months of the year are a good time to work on drip irrigation systems because 1) the plants demand less water when its cool, 2) the leaves are off of our deciduous plants and we can see the system better and, 3) the cool weather is much more pleasant for us to work in than the 100 plus degree weather of June and July, the time when we usually find drip system problems.  A little extra attention now can save a lot of grief later on.

Well designed and managed drip irrigation systems deliver the proper amounts life-giving water to the root zones of plants.  When everything works as it should, plants flourish.  When the system does not work properly, well, let’s just say that problems can arise.

In order for any plant to be healthy, there must be a balance of energy between the top part of the plant and the bottom part of the plant.  Stated another way, there must be sufficient strength stored in the roots to support the activity of the leaves; and there must be generated enough energy in the leaves to support the function of the roots.  When any plant goes out of balance, for whatever reason, serious problems can occur.

For example, when root systems die back because of disease or lack of water, there are less roots to support the top growth of the plant, leaving more branches and leaves than roots.   The plant is out of balance.  Because there is not enough strength to balance the top, the tree begins to lose leaves and sometimes even twigs and branches in severe situations. 

When I see a tree or shrub with sparse leaves and maybe twigs dying back, I am immediately suspicious that the roots are, for one reason or another, not getting enough water.  If you have a tree or shrub in your yard, it is a good idea to look critically at the growth patterns at least once a year.   While problems are easy to see in the summer, that is exactly the time when the plant is under the greatest stress and when most damage occurs.  For this reason, I like to check for problems in the late spring at the latest. 

Flood irrigation has its own set of rules and challenges, but today we are talking drip systems so lets focus there.  Remember, most of the small feeder roots that do the work of absorbing nutrients and water from the soil are going to be found out towards the edge of the plant.  Placement of emitters is one of the first places to look for problems.  It is important that our system wet as much of the soil where these roots are found as possible.  A large tree is going to take more than one or two emitters.  If you need to add emitters, start there.

Other problems arise within the system itself.  This is where regular inspection and maintenance pays off.

First, I like to start with the filter, usually found at the upper end of your system next to the water source.  It needs to be cleaned at least twice a year. To check the filter, open the filter canister and visually inspect the filter. If it is clogged, rinse or scrub it lightly until it is clean.  If the filter is damaged, it will need to be replaced.  Never run a system without a filter because any debris, even the tiniest, can clog emitters down the line.

Check the valves and make sure that they are working correctly.  If the timer tells a valve to turn on, and it doesn’t obey, you may have a faulty valve, a broken or frayed wire or a clog in the equipment.  You will need to troubleshoot this problem before going down the line.

If the valves turn on and off correctly, check the emitters while the system is running.  Danger signs include puddling of water on the surface of the soil away from the emitters or no water coming out of an emitter.  Puddles or wet soil away from the emitters usually means a broken or cracked line.  It will need to be replaced.  If there is no water coming from an emitter while the system is running, it generally is an indication of a clogged line or plugged emitter. These must be cleaned or replaced. 

Don’t forget that some leaks in drip system lines may actually be caused by small animals in search of a drink of water.  Gophers, rabbits and other animals frequently will chew on tubing above or below ground and then enjoy the water fountain.  If this is the problem, repairs can get frustrating.  You may want to fix the animal problem at the same time.

Finally, the entire system needs to be flushed out twice a year because debris, algae and salts tend to accumulate in the lines over time.  To flush out the lines, simply remove the end cap of the line and let the system run for thirty seconds.  This will allow all of the bad stuff to run out of the line.  The end cap can then be replaced.  Work your way through the entire system until all lines have been flushed.

Once you have checked your system and fixed problems you should be in good shape for the season.  This is not to say that there may not be a problem tomorrow.  Anything can break, but at least you are starting fresh.  To prevent system failures, it is a good idea to check the equipment regularly to see if anything has gone awry. 

Let me finish with a final note.  Do not forget to adjust your irrigation schedule as the weather warms. Plants require and use more water during the warm months than they do in either the spring or fall.  The hotter the weather, the more water plants will need.  When the weather cools, the opposite is true. 

Correct timing requires regular adjustments to the time clock to make sure the plants are getting enough water.  If you have set your timer once and never looked at it again, your plants may be getting too much water in the winter and not enough in the summer.  If indeed this is the case, please do not blame your irrigation system if plants die.  It is not the system, it is management.

Now is a good time to service your drip irrigation system.  A little preventative maintenance now may save a lot of grief later on.

If you have questions, you can reach one of the Master Gardeners at the Cooperative Extension office, 820 E. Cottonwood Lane, Building C, in Casa Grande.  The telephone is (520) 836-5221, extension 204.  The author’s email address is gibsonrd@ag.arizona.edu.

The University of Arizona is an equal opportunity, affirmative action institution.  The University does not discriminate on the basis of race, color, religion, sex, national origin, age, disability, veteran status, or sexual orientation in its programs and activities.

Rick Gibson
Extension Agent, Agriculture
University of Arizona Cooperative Extension
820 E. Cottonwood Lane, Building C
Casa Grande, Arizona 85222
Voice:    (520) 836-5221
Fax:    (520) 836-1750
email:    gibsonrd@ag.arizona.edu