A Step-by-Step Guide to Maintain your Drip Irrigation System
by: Nina Colasurdo, DIG Corporation
When watering landscapes with drip irrigation systems it is important to recognize that systems need, at a minimum, yearly maintenance, even preferably twice a year. Drip systems need to be thoroughly checked for broken and/or damaged components to ensure plants are getting all of their watering requirements met. Below is a guide to help navigate you through an annual physical for a drip irrigation system. A step-by-step check up of each component will uncover water wasting problems and damaged components. Repairing or replacing these components is much easier and less expensive than sprinkler systems and does not require a lot of digging, gluing or expensive supplies.
Step 1-Check the pressure. Go to each lateral valve and check that pressure is operating in the correct range. Most drip systems operate in a range of 20 to 50 psi. High pressure is typically the reason for a drip irrigation system to malfunction. Emitters operating at high pressure will not provide the correct flow rates and will frequently pop off the tubing, resulting in a significant waste of water. Fittings, both barb and compression, will be subject to failure due to excessive pressure. Operating pressure that's too low will result in reduced performance, and again, flow rates of emission devices will be affected. If pressure is too high, install or replace the regulator, and if pressure is too low, consider removing the regulator or increasing to a regulator with a higher pressure threshold.
Step 2-Check the controller. Turn on the controller and perform a manual run to operate each valve. Make sure all valves are opening and closing properly with no signs of leaks around the solenoid or flow control. Run irrigation, for each valve zone, long enough to walk the site to check thoroughly for leaks or defective emitters. Mark leaks with landscape paint or flags. Check the timer run times to ensure that plant watering requirements are met but not over watered.
Step 3-Check the filter. Today with the use of many different water types, i.e. grey water, re-claimed water, it is imperative that the proper filter size and type of filter is installed to protect your drip irrigation system. Filters can drastically improve the longevity of your emitters by helping to prevent clogging from sediments and other contaminants present in the various water types. Disk filters are excellent at catching sediments while resisting chemical elements in water. They are easy to extract and clean with a hose, then replace back into the filter housing. Mesh filters are also beneficial and can be easily removed and replaced if the sediment has accumulated. When choosing a filter, look for a large filtration area which will allow longer intervals between cleaning.
Step 4-In each valve zone, check fittings to make sure each has a secure connection. If tubing is popping out of the fitting, make sure the right sized fitting is used on the right size tubing. Different manufacturers make different diameter tubing. It is important to know your tubing ID (inner diameter) if using barb fittings or OD (outer diameter) if using compression fittings. Using the wrong sized fitting for your tubing diameter can result in a faulty connection. It only takes one blown connection to lose a substantial amount of water.
Assuming the pressure is regulated, high quality fittings do not blow apart since the compression rings are inserted to the fittings and welded. The weld secures the fitting to the compression ring, which results in a longer field life. Fittings using high impact material will stand up to foot traffic and weather extremes.
Step 5-Repair leaks marked with landscape paint or flags. When repairing tubing, cut out all the tubing with damaged parts. One challenge repairing tubing that has been installed a few years is that the sun and internal pressure changes the outside diameter of the product. Sometimes getting a fitting to slip onto existing tubing can be difficult if the cut is made too close to the warped/damaged tubing. To get a sturdy repair, use a patch of new tubing and connect it to the undamaged part in the line so that the fitting slips onto it easily to provide a secure connection. After the repairs are complete, open the closed end of the line and flush the line of all sediments and debris that can accumulate in the tubing. Re-pressurize the lines, run irrigation once more and check for leaks again.
Step 6-Cover drip irrigation tubing with mulch. Take care to cover bare spots where tubing is exposed. Mulch is great for conserving water by helping to prevent evaporation, and also reduces weed growth.
For aesthetic purposes, drip irrigation systems can be easily installed to become virtually invisible amongst the landscape. Tubing and emitters should be hidden in a landscape and not poking out like plastic sticks and weeds. Proper use of mulch and placement of emitters can significantly cut down on unsightly exposed components. A tidy, well maintained drip irrigation system is a lot easier on the eyes than unsightly bare spots, puddles and wilting plants.
When maintaining or installing a drip system, it would be prudent to use commercial grade plastic products that can withstand poor water quality, UV exposure, and varying climatic changes. Commercial grade plastics are impact resistant and will add to the longevity of a drip system. An entire system built with low grade components will break down much more quickly and even replacing the entire system might be needed.