Important Irrigation Installation Update
General Information about Backflow Prevention
People often think water travels in only one direction through the distribution system, but under certain pressure conditions, water can actually travel backwards. If a customer's water supply line is connected to a substance not fit for drinking and the line is unprotected, then the unfit substance could travel backwards through the water distribution system.
This is known as backflow.
Consider a hose submerged in a bucket of garden chemicals. If the water pressure in your area becomes lower than normal, the chemicals in the bucket can flow backwards through the hose and into your drinking water supply.
Backflow Brochure (pdf 792k)