Backflow prevention
Although the water that reaches your home or business is pure and tasty, contamination
can occur within your own piping system. This potential water contamination hazard
is called "backflow" or a "cross-connection."
A cross-connection is an accident waiting to happen. Any time the drinking water
supply comes in contact with an objectionable or harmful substance, a cross-connection
is created.
These cross-connections can lead to contamination when a change in pressure within
the piping system, such as a water main break, allows contaminated water to flow
back into the drinking water supply. For example, placing a hose in a bucket of
detergent creates a cross-connection and can lead to a possible health hazard should
a backflow occur.
The simplest solution is to always avoid placing hoses or connecting pipes to non-drinkable
fluids. Most modern fixtures and appliances such as sink faucets, toilets and clothes
washers have built-in backflow prevention devices.
Many backflow devices require annual testing. Irrigation systems also require a
city plumbing permit. The following is a short list of systems that require additional
backflow protection; some require annual testing of the device.
Click here to read a brochure about how to keep your water drinkable.
Fertilizers, pet waste, pesticides and other chemicals common to landscaped areas
can flow into irrigation piping through sprinkler heads or cracked pipes when sprinklers
are not in use.
State law requires that all irrigation systems be equipped with an Oregon Health
Division-approved backflow prevention device. This is required for all new and existing
irrigation systems. The irrigation system and backflow device must meet all appropriate
plumbing codes.
All irrigation systems using water supplied by EWEB or any other public water system
require a plumbing permit prior to installation. Permits are issued by the city
of Eugene (not EWEB), and a city official will inspect and approve your system prior
to completion. The city's permit office is at 99 W. 10th Ave.; the phone number
is 682-5086.
Irrigation systems also require an annual inspection to make sure the backflow-prevention
device is working properly. Inspections must be performed by a certified tester/inspector,
with annual notification made to EWEB that the proper testing was performed. For
a $35 fee, EWEB can arrange to have a certified tester do this work for you, but
you are not obligated to use this service.
Call EWEB at (541) 685-7000 to arrange for an annual inspection, or to obtain a list of
state-approved backflow-prevention devices and certified testers. If you are installing
an irrigation system yourself, many home-improvement centers also can help you select
an appropriate backflow-prevention device.
Chlorine and other chemicals used to keep your pool and spa bacteria free can be
harmful to drinking water. Some pools have direct connections that require a backflow-prevention
device and annual testing. When using a hose to fill a pool or spa, be sure that
the hose end does not touch the water in the pool.
The pressure in some well pumps can overcome the city water pressure and create
a backflow, if the two systems are connected. Untreated water can have harmful bacteria
or other contaminants.
Water within these systems often sits stagnant and can have chemical additives.
These systems usually are installed by professionals who have knowledge of any requirements
for backflow-prevention devices.
Access a list of certified backflow testing contractors that you can use in Eugene.
If you have any of these systems in your home or workplace, and need additional
questions answered, call EWEB Water Management Services at (541) 685-7000.