Grounds Care: Irrigation Practices to Save Water
May 25, 2011 - Contact FacilitiesNet Editorial Staff »
This is Chris Matt, Managing Editor — Print & E-Media with Maintenance Solutions magazine. Today’s tip is reducing water use during irrigation. The goal in irrigation is reducing use of potable water in landscapes — ideally, by about 50 percent from established baselines. Managers can use many methods to achieve this reduction. Inefficient irrigation is a big culprit in water waste. Most irrigation systems installed more than five years ago operate at less than 45 percent efficiency. WaterSense guidelines from the U.S. Environmental Protection Agency require a minimum of 70 percent efficiency. How can managers gain 25 percent in efficiency? First, conduct a water audit and try to pinpoint waste and recommend strategies for savings. These strategies likely will include installing flow meters that monitor and control use in irrigation areas. Most systems have automatic shutoff features, so if a line happens to break, water flow will cease. Another tactic is placing decorative fountains or flowing ponds on timers so they shut off periodically and during non-business hours. From an efficiency standpoint, drip-irrigation systems are an excellent option. The lines run about 2 inches below the surface, and water drips directly into the roots of plants. Drip-irrigation systems have an efficiency of 95 percent, compared to 50-65 percent efficiency of a traditional, overhead system. Workers also can remotely monitor newer, smart irrigation systems, which can automatically adjust for changing weather conditions. If it is raining, the system shuts off to curtail water waste. Also, soil sensors measure moisture levels and transmit the data to the system’s master control box. So water flows only when needed. If an existing irrigation system requires optimizing, managers can use several efficiency strategies. One strategy involves replacing older irrigation heads. Newer models can greatly improve the accuracy of water disbursement. These models water turf and plantings based on the individual amounts required, rather than overwatering in some areas and underwatering in others. Managers also can have irrigation systems designed and installed so trees, shrubs and ground cover are in separate hydro-zones. As plants become established, the system adjusts or discontinues watering by zone.