How do I Winterize My Sprinkler System?
Typically in the winter months in northeast Texas, sprinkler systems are rarely exposed to freezing temperatures. We have hot, hot summers preceded with and followed by beautifully comfortable springs and autumns. In areas of the country where there is a distinct winter season in which temperatures remain below freezing for an extended period of time, causing surface soil to freeze, extensive measures are taken to protect sprinkler systems from getting damaged from freezing water.
In the Pearson Sprinkler Company service area, the winters can become cold, temperatures can dip below freezing(32ºF) overnight, and we may even have a few days where the daytime temperatures will stay below freezing. For the most part, overnight freezing is typically followed by above freezing daytime temperatures. However, our area still needs to be irrigated during the winter months due to drying wind and daytime temperatures.
In our service area, we generally donot winterize sprinkler systems by draining the pipes in the winter, as the soil insulates them enough to prevent the water from freezing. If there is any aboveground equipment, it will need to be insulated to prevent freezing during the cold nights. To accomplish this, wrap the aboveground pipes with foam or fiberglass insulation, extending down underground to below the typical freezing depth. Where exposed to sunlight, wrap the insulation with a high-grade pipe wrap tape that is UV resistant, or with metallic tape. For aboveground valves and backflow prevention devices (not common in our area), you can purchase insulating covers that can be placed over them like a bag or you can wrap them in fiberglass pipe insulation wrap. Make sure that water can drain out the bottom in case there is a leak. The fiberglass insulation must be wrapped with plastic tape or something else waterproof to keep it dry.
Problems arise when our area experiences hard freezes that last for several days. Most recently, this happened in February 2010. We experienced five days of continuous below-freezing temperatures, causing pipes in buildings, utility pipes and sprinkler system pipes to break, causing extensive damage. You may recall that this occurred during the five days leading up to the 2010 Super Bowl located at Cowboys Stadium in Arlington. In situations such as this, winterizing sprinkler systems with insulation doesnot work well as the cold air has time to penetrate through the insulation, cooling the pipes and water inside. In areas where freezing weather lasts longer than overnight (rare in our area), but you still need to keep the irrigation system operational, it is a good idea to install electric pipe heaters on backflow prevention devices and aboveground valves.