Backflow Prevention

What is Cross-Connection

Cross-connections occur when safe drinking water mixes

with other unknown contaminants. If backflow occurs,

these contaminants could mix with the potable drinking

water system, possibly causing the water to have

unusual tastes, odors or colors. Backflow preventers are

required to prevent possible cross-connections. A cross connection

could occur when a garden hose is left in a

pool or in a basin with soap, such as when washing a

car. Water could flow back through the hose and into the

community water supply.


What is being done to prevent backflow

The State of Florida and federal government mandate

backflow prevention programs. According to the U.S.

Environmental Protection Agency, proper maintenance

of a water distribution system must include a backflow

prevention program. Florida statutes also require a

backflow prevention device. City ordinance 97-148

mandates backflow preventers to protect the public

water supply from possible contamination. The City

code applies only to commercial properties and multifamily

residences with three units or more.


Why do I need to install and certify a backflow preventer

Backflow prevention devices must be installed on

multi-family properties with three or more units, as

well as on commercial properties. Since 1997, the

 Building Division has been enforcing installation

of prevention devices on all new development. Prior

to 1997, installation and certification was voluntary.

 Water Utilities Division staff has

been conducting an inventory of properties that do and

do not have a backflow preventer. All City facilities have

backflow preventers in place.

Recently, the Florida Department of Environmental

Protection discussed amendments to the state

Administrative Code requiring community water supply

providers to submit a written report, which includes

compliance with backflow prevention policies. In addition,

the County Health Department requested

records to document a Citywide compliance program. The

City is now following federal, state and local mandates

to make sure all properties have backflow prevention

devices to keep the water supply safe.


 Backflow devices are used in plumbing systems

to decrease the chances of potable water being contaminated by any

debris and/or particles that may gain access into the water and "backflow"

into the main water supply.

There are only a couple of backflow devices that are commonly used.

These would be Doublecheck Valves and Reduced Pressure

Principle Valves. A Double Check Valve (also known as a

doublecheck, double check assembly, DC or DCA) has two, one way check

valves inside, in sequence, that allow supply water to enter but, if working properly,

will not let the water "backflow" into the potable water. The Second

device, a Reduced Pressure Principle Device

(a.k.a RP, RPZ, RPP, RPPZ) is similar to the device above but

has additional protection for the potable water, which is an extra

valve in between the two check valves that will open, releasing the water

out of the relief valve port under the device if it senses one of the check

valves to not be closing or sealing completely. Both of these

devices are testable by test ports on either side of the checks, allowing

a backflow tester to test and certify that these valves are working properly.

If the devices do not pass the inspection then it can either be repaired or replaced.