- Why does the James City Service Authority (JCSA) have a Backflow Prevention and Cross Connection Control Program?
- What is a cross-connection?
- What is backflow?
- What is backpressure?
- What is backsiphonage?
- Why do water system operators need to control backflow?
- Are all residential homes required to have backflow assemblies?
- Why are irrigation systems considered to be hazardous to the water system?
- What type of backflow prevention assemblies are allowed in irrigation systems?
- How do I know if I have a backflow prevention assembly?
- Is there a minimum height that the backflow assembly must be installed?
- How often do I have to have my backflow assembly tested?
- How much will the inspections/maintenance cost?
- Will there be a list of certified testers available to us? Where can we view this list?
- Why is the testing contractor that I used before not on your list now?
- Will I receive notification when to perform my test?
- What if I don’t receive a letter?
- What do I do with my test report?
- What happens if my backflow assembly fails the test?
- What if I do not get my backflow assembly tested or fail to have an improperly working backflow assembly repaired or replaced?
- Are any other backflow devices required for residential homes?
- Why do we need hose connection vacuum breakers (HVB’s) on faucets and hose bibbs?
- Should a hose connection vacuum breaker (HVB) be used on frost-free hydrants?
First and foremost because we want to ensure that our water distribution system remains safe from harmful substances. It is also required by the Virginia Department of Health’s (VDH) Waterworks Regulations. We as your water system operator are required to have this program as a condition for the issuance of our water system operator’s license.
A cross-connection is any temporary or permanent connection between a public water system or consumer’s potable (i.e., drinking) water system and any source or system containing nonpotable water or other substances. An example is the piping between a public water system or consumer’s potable water system and an auxiliary water system, cooling system, well, or irrigation system.
Backflow is the undesirable reversal of flow of nonpotable water or other substances through a cross-connection and into the piping of a public water system or consumer’s potable water system. There are two types of backflow; backpressure and backsiphonage.
Backpressure is backflow caused by a downstream pressure that is greater than the upstream or supply pressure in a public water system or consumer’s potable water system. Backpressure (i.e., downstream pressure that is greater than the potable water supply pressure) can result from an increase in downstream pressure, a reduction in the potable water supply pressure, or a combination of both. Increases in downstream pressure can be created by pumps, temperature increases in boilers, etc. Reductions in potable water supply pressure occur whenever the amount of water being used exceeds the amount of water being supplied, such as during water line flushing, fire fighting, or breaks in water mains.
Backsiphonage is backflow caused by a negative pressure (i.e., a vacuum or partial vacuum) in a public water system or consumer’s potable water system. The effect is similar to drinking water through a straw. Backsiphonage can occur when there is a stoppage of water supply due to nearby fire fighting, a break in a water main, routine maintenance flushing, or any other situation that causes a significant loss in water system pressure.