Backflow Prevention

Backflow FAQs

What is backflow?

Modern Electric Water Company’s water system is designed to keep water flowing from our distribution system to you, the customer. Backflow can occur due to high pressure on the customer side, or low pressure in the Company’s water system. Backflow is the undesirable reversal of water flow in a potable water system through a cross-connection. This situation may allow liquids, gases, non-potable water, and other substances, from any source, to enter a public water system.

What is a cross-connection?

A cross-connection is a point in a plumbing system where the potable water supply is connected to a non-potable source. Briefly, a cross-connection exists whenever the drinking water system is or could be connected to any non-potable source (plumbing fixture, equipment used in any plumbing or irrigation system). Pollutants or contaminants can enter the safe drinking water system through uncontrolled cross connections when backflow occurs.

What is a Cross-Connection Control Program or a Backfow Prevention Program?

This program is required by the State of Washington to detect and prevent possible sources of non-drinking water from entering a public drinking water system. The program is a combined cooperative effort between plumbers, health officials, water system operators, property owners, and certified testers to follow guidelines for controlling cross-connections and implementing means to ensure their enforcement so that the public drinking water supply will be protected both in the city main and within private facilities. The elements of a program define the type of protection required and responsibility for the administration and enforcement. Other elements ensure continuing education programs.

Where are cross-connections found?

Every water system has cross-connections. Plumbing codes and State drinking water regulations require cross-connections to be controlled by approved methods (physical air gap) or approved mechanical backflow prevention devices or assemblies. The various types of mechanical backflow preventers include: reduced pressure backflow assembly (RPBA), reduced pressure detector assembly (RPDA), double check valve assembly (DCVA), double-check detector assembly (DCDA), pressure vacuum breaker assembly (PVBA), spill-resistant vacuum breaker assembly (SVBA) and atmospheric vacuum breaker (AVB). For a backflow preventer to provide proper protection, it must be approved for backflow protection, designed for the degree of hazard and backflow it is controlling, installed correctly, tested annually by a State certified tester, and repaired as necessary.

Visit the Washington State Department of Health's page on Cross-Connection and Backflow Prevention for more information.

What is the most common form of cross-connection?

The ordinary garden hose is used to create the most common form of cross-connection. A hose can be easily connected to the drinking water supply and used for a variety of potentially dangerous applications. An example would be a garden hose attached to a service sink with the end of the hose submerged in a tub full of detergent. Another example would be a garden hose attached to a faucet and the other end lying in a swimming pool. Another example would be a garden hose attached to a faucet and the other end attached to a fertilizer/pesticide handheld sprayer.

Who needs a backflow preventer?

Backflow preventers will be required if an actual or potential hazard for a cross-connection exists. A few examples of hazards include:

  • Commercial and Residential Irrigation Systems
  • Fire Sprinkler Systems
  • Medical Facilities
  • Processing Plants

Modern Electric Water Company will determine which type of protection is required based on the degree of hazard that the property represents to the drinking water supply.

How would a backflow issue occur in a commercial building?

An example of this situation includes customers observing yellow water flowing from a drinking fountain and green ice rolling out of an ice machine. The contaminants were traced to an error by a maintenance person. A pump for the air conditioning system burned out and the maintenance person, unaware of the danger, connected the system to another pump used for potable water. The result caused large doses of bichromate of soda to be forced into the drinking water supply, causing the dramatic appearance of yellow water and colored ice cubes.

Why does a soft drink dispensing machine require backflow protection?

Soft drink dispensers (post-mix carbonators) use carbonated water mixed under pressure with syrup and water to provide soft drink beverages. Many, if not most internal water pipes, are made of copper. When carbonated water comes into contact with copper, it chemically dissolves the copper from the pipe. This copper-carbonate solution has been proven to be a risk to the digestive system.

Is my home or business “Grandfathered” In?

There is no “grandfathering” of backflow devices which are out of compliance with current regulations. The State considers backflow regulations to be a health and safety issue. These issues must be addressed in a timely matter for the safety of the public water supply and the health of our customers.

Why is Modern Electric responsible for enforcing the rules, since they are State of Washington rules?

The Environmental Protection Agency (EPA) enforces the backflow regulations by delegating the responsibility to the State. The Washington State Department of Health/Office of Drinking Water then enforces the backflow regulations by requiring the water purveyors to administer the backflow program locally. Modern must report to the State annually to determine it is administering the program according to regulations.

Who do I call to have a test completed?

Any certified backflow prevention assembly tester who is registered may be called on to test the device. If the device is located on a fire system, the tester must be employed by an Approved Fire line Tester. The tester will return the original report of the test to Modern and will give the customer a copy of the test report.

What will a test cost?

The cost of having a device tested varies among testers. The cost is also dependent on several factors, including the size of the device, where the device is located, the type of device, etc. You may want to call several Certified Testers to obtain quotes for your test.

Modern Electric Water Company’s List of Backflow Assembly Testers for 2022

The following Washington State Certified Backflow Assembly Testers have requested that Modern Electric Water Company include them on this list. This is just a partial list of testers in the area who are qualified to test backflow preventers.  We suggest securing several estimates for testing your Backflow Device(s). If your test fails, not all testers are certified to make a repair, it is a good idea to ask if your tester is also certified to repair/replace a failed device.

Name Address City State Zip Phone
B&B Sprinklers Inc. PO Box 520 Mead WA 99021 (509) 466‐7550
DW Landscape 3110 East Chattaroy Road Trail 43 Chattaroy WA 99003 (509) 999‐5829
McKinstry Co. 850 East Spokane Falls Spokane WA 99202 (509) 625‐3100
ABC Fire Control, Inc. 1113 North 6th Avenue Yakima WA 98902 (509) 453‐3434
Inland Backflow, LLC 3923 East 34th Avenue Spokane WA 99223 (509) 852‐3115
Herres Backflow & Construction PO Box 10180 Spokane WA 99209 (509) 919‐4970
Aqua Pro Sprinklers 808 West Woodway Avenue Spokane WA 99218 (509) 990‐8766
Saphire Springs 11811 East Grave Spokane Valley WA 99206 (509) 703‐8714
Senske Services 7115 East Cataldo Spokane Valley WA 99212 (509) 532‐7881
Backflow Johnny 18208 North Astor Court Colbert WA 99005 (509) 998‐5651
Inland Empire Fire Protection 3832 East Boone Avenue Spokane WA 99202 (509) 534‐1097
Lilac City Sprinklers PO Box 14768 Spokane WA 99214 (509) 922‐8900
Roe Backflow Testing 1716 East Francis Spokane WA 99205 (509) 484‐0225
A Better Backflow LLC 17213 North Meadowview Lane Spokane WA 99026 (509) 440‐2871
Modern Electric Water Co Does not test fire systems/commercial properties/repair backflow devices (509) 928‐4540
Bastin Backflow Testing and Service 14809 East Rich Avenue Spokane Valley WA 99216 (509) 951‐3914
Bigfoot Backflow LLC PO Box 464 Liberty Lake WA 99019 (509) 844‐7066
C&C Yard Care PO Box 18768 Spokane WA 99228 (509) 482‐0303
Auto Rain Contracting LLC 2938 North Martin Street Spokane WA 99207 (509) 487‐3430

Backflow Prevention Assembly Test Report