Commonly Asked Questions

What is a Backflow prevention program?

It is a program required by the California Department of Public Health (CDPH) to detect and prevent other (non- drinking) water sources from entering the public water system.

What is a cross-connection?

Cross-connections potentially enable other (non-drinking) water sources of unknown quality to co-mingle with the public water system. Our backflow prevention program identifies and prevents cross-connections. A backflow prevention device will be required if a potential for a cross-connection exists.

If your home water system is connected to a source of water other than your water supply - a cross-connection has occurred.  "Indirect" cross-connections may occur by garden hoses and temporary connections that may be connected for only a few minutes. Direct cross-connections are more permanent hard-pipe arrangements.

What is backflow?

Backflow is the backward flow of water through a pipe into the public water system. The normal direction of water flow is from the utility water main to homes or businesses. The backflow of water from home plumbing systems into community drinking water happens when water is pulled backward due to a pressure loss in the utility main pipe or pushed back by a pressure source like a well pump.

How can this happen?

Contamination of drinking water is usually the result of cross-connections of piping between your drinking water and some other source such as irrigation well, pond, swimming pool or Clear Lake. The American Water Works Association (AWWA) estimates over 100,000 cross-connections occur each day - half of these from garden hoses. Backflow preventers are designed and installed to prevent the flow of water backwards through the pipe.

What is an indirect cross-connection?

This is a temporary cross-connection that may exist for a short period of time. A good example of an indirect cross-connection is a garden hose attached to an outside hose bib with the end of the hose submerged in a pail, swimming pool, or pesticide dispenser. Of additional concern is that some people use the garden hose to flush out sewers and drain pipes.

If I have a well that is not connected to drinking water, do I still need a backflow preventer?

Yes. Lake County Ordinance No. 1462 requires a backflow prevention device for wells. If your well is not currently cross-connected, the potential exists for a connection to occur during pump priming, maintenance, or alteration of your irrigation pump and well.

Why does this backflow preventer need to be installed in the front of my house?

In order to protect the community water system as much as possible and meet state requirements, the backflow preventer needs to be installed as close to the water meter as possible.

Can I cover or hide the backflow preventer?

Yes, there are several methods to cover and protect the backflow prevention assembly from weather, vandals, and lawn mowing equipment.

Why do backflow preventers need to be tested every year?

The backflow preventer is a mechanical device that needs maintenance just like a car. The annual test indicates if the internal check valves and mechanics are working properly and protecting your water.

My backflow preventer sometimes leaks water from a relief valve. Can I remove or plug the valve to prevent water loss?

The relief valve is installed to prevent water pressure from building up too high when the water in a water heater expands. The relief valve can be replaced with a small expansion tank that does not leak. Plugging or removing the relief valve could cause damage to your water heater or plumbing.