The simplest form of water conservation upgrade can be a wireless rain sensor, which saves an average 10 percent of water use. On the high end of control upgrades are “Smart” irrigation controllers that adjust irrigation schedules on a daily basis depending on weather conditions. Studies have shown Smart controllers can save up to 30 percent of water use depending on prior management practices. New products are arriving on the market that are more cost effective and user friendly, making Smart controllers an easier sell — especially on residential projects.
Replacing existing spray nozzles with rotary nozzles, such as MP Rotators, or incorporating them into a new system design provides greater water savings and drastically increased efficiency. In many cases, rotary nozzles can be successful in improving poor-performing spray systems due to low pressure. Because rotary nozzles require less water to operate, they have the advantage of reducing friction losses in an existing system and improving the operating pressure at the head. Additionally, due to lower water requirements of the nozzles, more area can be irrigated with fewer zones, reducing system costs with fewer valves and smaller controller sizes, as well as less pipe, wire, fittings and labor.
Drip tubing with pre-installed, in-line emitters offers substantial advantages over traditional irrigation methods in not only water savings, but also time and cost considerations. In many cases, the tubing can be simply “snaked” through planters and then mulched over. Winterization can be a snap by incorporating threaded caps on line ends that can be removed for blow out.
On any projects with elevation changes, check valves should be installed, at the very minimum, on the lowest heads. One hundred feet of 1-inch pipe on single zone can waste 4 gallons of water per zone cycle through low-head drainage. On a 12-zone system, that equates to 48 gallons per irrigation day. Beyond saving water, check valves will also protect the sprinkler from the water hammer that occurs every time the valve turns on (and water rushes to fill the empty lateral line), greatly increasing sprinkler longevity.
One last note when working on improvement of older existing systems: sprinklers should be reset to proper grade level, screens cleaned, and nozzles replaced. Nozzles on both spray heads and rotors will wear over time and lower the ability for water to be sprayed efficiently. It is a good idea to check with your local irrigation distributor to see if there are newer, more efficient nozzles available for existing, installed sprinklers.
Troy Leezy is marketing manager for Hunter Industries, and is a certified irrigation designer, water auditor and water conservation manager.