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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:

Underground sprinkler systems
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 984-4747 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.

Pools and spas
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.

Wells
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.

Heating, cooling and fire-sprinkler systems
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.

Backflow testing contractors
Access a list of certified backflow testing contractors that you can use in Eugene.

Contact us
If you have any of these systems in your home or workplace, and need additional questions answered, call EWEB Water Management Services at 984-4747.