Every Spring, irrigation installers receive phone calls from frantic property managers and homeowners; the ringer may as well sound like coins hitting the collection tray of a slot machine. The reason they’re calling – their in-lawn sprinkler system was not properly winterized and the pipes burst upon freezing leaving nothing more than scattered pieces of pvc buried in the lawn. The average cost of a sprinkler system installation in Georgia is over $2,600 and can be much more depending on property size and quality of parts used. Don’t pay for that system twice (plus the labor to dig out a destroyed system) simply because you did not follow a few simple steps to protect it.
In areas of the country where temperatures fall far enough below freezing for extended periods resulting in frozen soil, having your irrigation system winterized should be an annual task (for areas in warmer climates that do not experience deep freezes, simply turn off your irrigation system during the winter months when it will not be in use). This process is relatively easy to perform and can literally save you thousands of dollars and a huge headache. Healthy, deep rooted lawns are resilient; depending on your geographic location and the year’s weather, you can stop watering your grass in Autumn well before the threat of the first freeze.
Every irrigation system is different, consult the installers or your owner’s manual for specific procedures but the overall process typically consists of the following:
A. Shut off the water
Locate the main valve connecting the system to the water supply and turn it off completely.
B. Drain the pipes & Relieve air pressure
The biggest goal of winterization is to completely remove all water from within the irrigation system. If water remains, it will expand upon freezing and potentially crack or burst the pipes rendering them useless. Water left to freeze in the backflow assembly can also crack the brass housing and damage internal components. There are three methods for draining your pipes depending on the system installed:
Manual Drain Method – if your system has manual valves located at the ends and low points of the piping, simply open them and let the water drain out. Make sure you’ve located and opened all such valves. There may still be water between the shut off valve and the backflow device which needs to be drained as well; to do so, open the drain cap on the stop and waste valve or the boiler drain valve depending on which you have. Open the test cocks on the backflow device and if your sprinklers have check valves, pull up on the sprinklers to allow any remaining water to drain.
Automatic Drain Method – if your system has automatic drain valves, they should open and drain the water when the pressure in the pipe falls below 10 PSI. Shutting off the water supply and activating the system pressure relief station will initiate the opening of the drain valves. Once drained, follow the same steps above in the Manual Drain Method to ensure all water is out of the backflow device and sprinklers.
- Blow Out Method – this method involves using a high capacity air compressor to forcefully blow out all water in the system. There is potential to harm yourself or your equipment (flow sensors, pipes, backflow devices, etc) if you do this wrong. So, it should only be conducted by qualified licensed professionals. Small shop compressors (1-3 HP) are not suitable for this task as they do not have a great enough air capacity to do the job.
C. Close all drain valves
When the entire system is completely drained, close all of the drain valves (either manually or using your automated system) to ensure debris, groundwater, insects or other critters do not find their way in.
Now that your irrigation system has been properly put to bed for winter, you can rest assured that when Spring rolls around, you’ll be able to maintain a beautiful green lawn without spending too many more greenbacks.