Why do many sprinkler companies program their sprinklers to run for forty-five minutes per zone? This is a great disservice to the customer and the contracter alike. I have seen no benefit to the lawn or the customer to have water running down the street. I have rubbed many contracters the wrong way after sodding a new lawn and changing the programs. The rule for new sod is not quanity but frequency of watering. On my existing lawn, I run my sprinkler system for ten minutes per zone, three times in a row. This puts down one-half inch of water with no runoff. I do thi three times a week, which is a good amount for this area and promotes good root development.