Water Quality

Cross Connection/Backflow Prevention

Water Quality

1. My water tastes funny.  Why?

Is there a garden hose attached to your outside faucet?  Is the water turned ‘on’ but suspended from flowing by a garden hose nozzle? If so, this can cause the water to back up into your system and the strange taste is coming from the garden hose at the outside faucet.  If the hose is not the problem, the district can send someone out to flush the water line and troubleshoot the problem with you. They will flush the line if necessary.

2. My water smells strange.  Why?
The District can send someone out to troubleshoot the smell with you.  They will flush the line if necessary.
3. Is the water fluoridated?
Yes.  There is one part of fluoride per million parts of water.
4. Is my water hard or soft?
Woodinville’s water is purchased from Seattle Public Utilities and comes from the Tolt Watershed.  This water is soft, at 1.40 grains per gallon.
5. Why is my water discolored?
There are many reasons for discoloration. One of the most common problems is the need to flush the hot water tank.  Natural vegetation and debris settle in the bottom of the tank and should be flushed out annually. This will help with discolored water generally noticed in the bath tub and will also improve the longevity of your tank. So, if your hot water is discolored and the cold water is clear this may be a simple solution to your problem. Flushing instructions are available at the District office.
Another common cause of discoloration is a dead-end main line serving your home. This would be noticed in the cold water.  Woodinville Water has numerous dead end lines. The same debris that ends up in your hot water tank also comes to rest in the bottom of the main line and even more so in dead ends. If you think this problem is occurring, contact the water district. We have apparatuses at the ends of these lines that enable us to flush them out. All dead end lines need this service on occasion.
Construction in your neighborhood will sometimes cause discoloration. This problem occurs when a water line is accidentally broken or the contractors are using water from a fire hydrant.  Anything that causes the water to flow at a higher velocity than normal can stir up the system which will result in discoloration.  After a main repair or shut down, the field crew takes great efforts to flush the debris from the line to insure clear water at your tap.
It's important to realize that even though your water is discolored because of the chlorine residue, it is still safe to drink.
Cross Connection/Backflow Prevention
1. What is a cross connection?
A link between your drinking water system and a source of contamination, a way for “bad stuff” to get into your good clean drinking water.
The term cross connection means any actual or potential connection (piping/hose) between a public water system and a source of contamination.
2. What is Backflow?
Do you realize that water can flow two directions in a hose or pipe? When water is flowing in the opposite direction from its normal flow that is backflow and it can put our drinking water in danger.
3. What are common examples of cross connection hazards (source of contamination) that need to be protected with a backflow preventer?
    • fire sprinkler system
    • lawn irrigation systems
    • auxilary water supply (wells)
    • hot tubs/spas
    • swimming pools
    • hose bibs/garden hose
    • boiler
    • boiler
    • carbonation equipment
    • film processors
    • fire systems
    • x-ray machines
    • dental equipment
    • etching tanks

Note: Toilets and sinks have an Air Gap for backflow protection.


4. Why is a backflow preventer necessary?

All it takes for backflow conditions to occur is a drop in line pressure in the water main, which can happen due to use of hydrants for fire fighting, water main break, high usage or backpressure.  In America, we all assume when we turn the tap on that 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.

5. What is the legal basis for a local cross connection control program? 
The Safe Drinking Water Act of 1986, and Washington State Administrative Code (WAC 246-290-490)  requires the Water District  to administer a Cross Connection Control Program that will protect the drinking water supply, and to coordinate with the Local Authorities that protect the drinking water supply from possible backflow hazards within the plumbing system of buildings.
6. Do I currently have adequate backflow protection?  And, how can I find out?   
If you have questions pertaining to your home or building contact the Woodinville Water District’s Water Quality Specialist
7. What is my liability as a building owner property manager and water purveyor?  
Legally, the “purveyor” of the water supply is responsible for the water quality and for implementing and maintaining a cross connection control program in order to prevent the contamination of the public water system.  The water purveyor is the public water department, up to and including the service connection from the water main.  From the outlet of the water meter or service connection including all piping down downstream inside the owner’s premise, the legal purveyor of the water supply is actually the property owner.
8. What are types of backflow protection?
An Approved Air Gap Separation
Mechanical Assemblies used in the prevention of backflow are separated into three types:  
    • Reduced Pressure Backflow Assemblies (RPBA) including Reduced Pressure Detector Assemblies (RPDA)
    • Double Check Valve Assemblies (DCVA), including Double Check Detector Check (DCDA)
    • Pressure Vacuum Breaker Assemblies (PVBA) and Spill-Resistant Pressure Breaker Assemblies (SVBA)
 Mechanical Devices used in the prevention of backflow include:  
    • Atmospheric Vacuum Breaker (AVB)
    • Hose Bib Vacuum Breaker device (HBVB), also known as a Hose Connection Vacuum Breaker
    • Dual Check with Atmospheric Vent, also known as a Backflow Preventer with Intermediate vent
    • Dual Check Backflow Preventer
    • Residential Meter Check 
9. How often do Backflow Assemblies have to be tested? 
Backflow Assemblies must be tested at the time of installation, annually after installation, after a backflow incident, and after any repairs have been made.  If an assembly is relocated and/or reinstalled it must be retested.  Anytime a backflow assembly is tested a test report needs to be submitted to Woodinville Water District.
10. Who can test the Backflow Assembly? 
To test backflow assemblies in the State of Washington a person must have a Washington State Department of Health Certification as a Backflow Assembly Tester (BAT).
11. What to do if my backflow assembly fails the annual test?
If your backflow assembly fails it annual test; it needs to be cleaned, repaired or in some cases it may need to be completely replaced.  After cleaning, repair or replacement a successful re-test performed.
Do you need more information or have other questions on backflow protection and cross connection?  Contact the Woodinville Water District’s Water Quality Specialist.