By Stanford Irrigation

06/22/2010 The supply line from the house goes into the zone box. From this point each valve controlls one zone. In this zone box there are three valves. Under the valves is a weed protection barrier. The barrier helps keep the zone box looking nice.

The lawn needs to be broken into zones for two main reasons.

There is not enough water supply to water the entire lawn. In Calgary the pressure is about 45-50 lbs, and the supply is about 11 Gallons per minute on a 3/4" supply line. Thats about 10 sprinkler heads depending on how much water each head uses.

The second reason to split zones is that area's in the shade need less water than areas in the direct sun. Wind and hills are also a factor.