"Cross Connection Program" Protects Drinking Water Quality

Cross Connections

The City of Silverton is mandated by state regulation and city ordinance to control and eliminate any actual, or potential, cross connection to the public drinking water supply. 

Backflow preventer (also called assembly) test reports are due to the City of Silverton annually from certified testers or homeowners between January 1 and June 1. Test should be completed during the same month annually, if possible. The Cross Connection Program is a vital part of keeping water safe throughout the water system. 

 

Important City of Silverton Cross Connection Program Updates

Effective February 26, 2026:

  • City of Silverton will no longer accept paper backflow assembly test reports.
    If paper reports are received, they will not be applied to the customer’s account.
  • All reports must be submitted electronically as individual PDF files for each assembly location. PDFs that include multiple assembly locations will not be applied to the customer’s account. Separate PDFs ensure results are applied to the correct assembly.

Please see the City of Silverton Backflow Assembly Tester List below under supporting documents. 

Staff Contacts

Public Works Admin Assistant II
(503) 874-2206

Frequently Asked Questions

If your irrigation system, boiler, fire system, swimming pool or spa was permitted through Silverton's Building Department, adequate backflow protection was required. If the fixture was installed without proper permits or testing, or you are not sure if you have adequate backflow protection, please contact the Cross Connection Specialist at 503-874-2206.  

The City maintains a database containing all the permitted backflow assemblies in Silverton. It is your responsibility to have your backflow assembly tested annually, during the month previously tested, between January 1 and June 1. The City currently sends out a courtesy reminder in the spring. Do not wait for the reminder; schedule your test during the month it was scheduled last year. All assemblies must be tested at least once annually so you do not need the reminder to schedule your test.  

It is the customer’s responsibility to schedule the test and make payment arrangements. Upon completion of the test, the customer will be given a copy and the tester will submit the results to the City. 

Backflow assemblies must be tested at the time of installation, annually (once a year) after installation, after repairs and after relocating or replacement. When Silverton customers have their backflow assemblies tested, a test report will be submitted to the City of Silverton Cross Connection Specialist by the tester. 

Examples include residential fire systems, wells or auxiliary water systems, lawn irrigation systems, boilers, and swimming pools and hot tubs that are hard piped for filling purposes.

Backflow assemblies are devices placed on cross connections to prevent water from backflowing into the water system. The most common type of backflow assembly is a double check valve assembly, which consists of two independent check valves, two resilient seated valves and testing parts.

A cross connection is any connection between piping that carries drinking water (also known as potable) and the piping or fixtures that carry other types of water or substances that are not safe to drink (also known as non-potable), and any matter that may change the color, taste, quality, or odor of water.

Drinking water normally flows in one direction (from the meter to the house), although under certain circumstances it can flow in the opposite direction, or ‘backflow’. A backflow incident can happen at any time. All that is needed is a water pressure drop in the public water system main line, most commonly caused by fire fighting, hydrant flushing, flow testing, a water main break, or extreme high usage on the water system. Any connection to a non-potable source not protected could be siphoned back into the public water system, which can pollute or contaminate the water system.

Backflow protection is necessary because we assume that when we turn on the water tap, we have safe drinking water. This is a luxury we enjoy, but not without very strong regulations and considerable expense. Our drinking water is among the safest in the world. Water protection and conservation requires the effort and cooperation of everyone. 

The federal Safe Drinking Water Act (SDWA) 42 U.S.C. 300f to 300j-26 has jurisdiction over the public health aspects of the drinking water supply. The Oregon Health Authority regulates public water systems in our state, including cross connection control, through Oregon Administrative Rules (OARs). One such rule is OAR 333-61-0070, which requires water districts to administer a cross connection control program that will protect the potable water supply. The City of Silverton, as required by OAR 333-61-0070, has passed an ordinance on cross connection control, Silverton Municipal Code Chapter 13.20.  

Legally the water supplier is responsible for water quality and for implementing and maintaining a cross connection control program to prevent pollution or contamination of the public water system. The water supplier’s responsibility ends at the outlet side (the customer’s side) of the water meter. Once the water is on the outlet side of the water meter or service connection, responsibility and liability falls to the owner. it is the owner's responsibility to keep backflow assemblies functioning and tested annually. 

View All FAQ's