If you have a typical lawn irrigation system, when you try to reduce the run time to save water, some areas always dry out first. Other areas still get enough water even with the run time reduced. Most people set their sprinkler run times based upon the “keep the dry spots green” rule. By installing Spray Smart valves with all the dry areas as “A zones” and the wetter areas as “B zones” each area can get exactly the water it needs with less waste. See How It Works.