How serious is the state in protecting our drinking water?

What is the cost of even one contamination?

Residential lawn irrigation is not only a high hazard (pesticides, herbicides, fungicides, animal feces, mold, and other soil contaminates), but conditions change constantly. Backflow devices not only fail to operate over time, but any change to an existing irrigation system can result in a backflow device falling out of compliance. An annual visit by a state-certified backflow tester is needed not only to test the device, but make sure the device is in compliance with current regulations. Basically, every homeowner with a lawn irrigation system, would not only need to be able to pass the state certification exam (administered to backflow prevention specialists), but also have a working knowledge of lawn irrigation. A "public education program", as the sole source of backflow prevention, would be inadequate and potentially dangerous. 

If there are concerns about the cost and implementation of this cross-connection and backflow prevention program, all you need to do is study the success of the program at James City County. Since 2008, residential lawn irrigation systems have been tested and cataloged with minimal cost to the homeowners and run by a very lean and efficient team of two. I can't see how a well-run "public education program" would cost any less than a well-run cross-connection department. And here I ask the question again, "What would be the cost of even one incident of contamination?".