A "cross-connection" as
defined by the Environmental Protection Agency, is any actual or
potential connection between the public water supply and a source
of contamination or pollution. More specifically, it is a physical
link that allows potential backflow incidents; permanent or
temporary piping arrangement which can allow your drinking water to
be contaminated if a backflow condition occurs.
In the event of a backflow or
backsiphonage event, such cross-connections constitute a hazard to
the building occupants and can jeopardize the cleanliness and
potability of the public water system.
What are Examples of Hazardous Cross-Connections?
Cross-connections happen when a hose,
pipe or a basin containing a substance other then drinking water is
connected to a potable water distribution system. When this happens
there is potential for backflow, or back siphonage.
Potentially hazardous cross-connections occurs every time
someone:
- Uses a garden hose sprayer to apply
insecticides or herbicides to their lawn.
- Places a hose in a bucket or
pool.
- Uses their garden hose to clear a
stoppage in their sewer line.
There are many other potentially
hazardous cross-connection scenarios. Please review the links below
for more information or call or email us directly if you have any
questions regarding cross-connection and backflow conditions.
Additional Cross-Connection information can be found
at:
What is Backsiphonage?
A backsiphonage condition can occur whenever there is a lowered
pressure between the potable and non-potable supply piping.
For instance, during the demands imposed by fire fighting
operation, or in the event of a water main break, the City water
pressure may suddenly drop to a pressure that is lower than that of
the non-potable system. This results in a partial vacuum
being drawn on the non-potable system, and siphons the pollutants
or contaminants into the potable water system.
What is Backpressure?
A backpressure condition occurs whenever an elevated pressure
exists between the potable and non-potable source. These
pressures can be imposed by the installation of pumps, which
increase pressures above the City water supply pressure, thereby
forcing non-potable water in the opposite direction of normal flow
into the potable water line. Boilers or other equipment,
which heat water causing thermal expansion and resulting in
pressures in excess of the incoming water pressure, also can force
non-potable water into the potable water piping system.
What is a Cross-Connection Control Program?
A cross-connection control program is an organized, legally
implemented and structured program to eliminate and contain the
hazards to municipal potable water supply. These programs
have been implemented and are typically passed by state or local
law, and enforced by the local water supplier, such as the City of
Dunedin.