DDW-2024-012271

Many public drinking water systems are contaminated each year by pollutants or con-
taminants that backflow into the water system through unprotected cross-connections.
Identifying and eliminating or protecting cross connections is a
matter of public health!
A cross-connection is a physical
connection (piping configuration) be-
tween the public drinking water system
and anything else, including another
water supply that can allow undesirable
pollutants or contaminants to backflow
into the public drinking water system.
Drinking Water Non-potable water or substance
Backflow is the reversal of flow from
a residential or commercial water system
back into the public drinking water system.
A backflow incident could occur if the wa-
ter systems pressure decreases, or the
customer’s water pressure is higher than
the water systems pressure. A backflow
incident could carry pollutants or contami-
nants into our public drinking water sup-
plies making them unsafe to use.
The Plumbing Code and the Utah
Public Drinking Water Rules require that
all cross connections be eliminated or pro-
tected against backflow by installing an
approved backflow device or assembly that
will insure that no impurities or contami-
nants are introduced to the public drinking
water supply.
Backpressure Backflow Backsiphonage Backflow
Yes! Several common cross connections are described below:

Threaded Hose Connections (Hose Bibs)

A large majority of backflow inci-
dents are created by the common garden
hose. Hoses can be connected to most an-
ything that may contain undesirable sub-
stances such as chemical sprayers, buckets
and pools, stock troughs. Plumbing Code
requires that all threaded potable water
outlets (hose bibs or sill cocks), except
water heater drains and clothes washer
connections, be protected by a non-
removable hose bib vacuum breaker or an
atmospheric vacuum breaker. The instal-
lation of a hose bib vacuum breaker is an
inexpensive way to protect against con-
tamination.
Landscape Sprinkling System

The Plumbing Code requires that
all landscape sprinkling systems connect-
ed to the public drinking water system be
equipped with an approved backflow
prevention device or assembly. Land-
scape irrigation systems could subject the
drinking water supplies to things such as
fertilizers, pesticides and animal waste.
Any sprinkling system that can
utilize both public drinking water sup-
plies and secondary water supplies must
follow specific plumbing regulations to
prevent raw water from entering the
drinking water system!
Please contact your local drinking water
supplier for specific requirements re-
garding landscape irrigation systems and
which type of backflow prevention is ap-
propriate for your landscape irrigation
system.
Call your local public drinking water agency or plumb-
ing inspector regarding cross connection control and
backflow prevention requirements in your area.

For further info, call the Utah Division of Drinking
Water at [phone].