A backwater valve is a one-way, free-floating door that works with the weight of sewage water travelling out of the home. When water flowing through the sewage line reverses direction, the door closes and seals, preventing sewage water from entering your basement.
What is a backwater valve on a sewer line?
A backwater valve is a one-way or check valve that allows sewage to flow in only one direction. It is installed on the main sanitary line that is a passage way for waste water from drains in your house into the municipal sewer line. Backwater valves aid in preventing sewer backups into your home.
How do I know if my backwater valve is working?
A backwater valve will stop water or sewage from flowing into your house should the main sewer line become overloaded. In most cases, you can check to see if it’s working properly by looking through the clear cover on the backwater valve access box. Inside the valve is a small flap that is normally open allowing water to exit your home.
Do I need a backwater valve in my home?
The risk of water backup increases if there is a basement in your home, or if the ground floor is less than a foot above street level. If a new home has any fixtures located lower than the street level, it is a requirement of The National Plumbing Code to have a backwater valve installed.
Why does a backwater valve have a clear top?
These valves often have a clear top so you can see if it is operating properly. There is a lid that can be removed for cleaning. Without a properly placed and installed backwater valve, sewage could come into the basement through a floor drain, sinks, tubs, and toilets.
How does a backwater valve work?
What is a backwater valve?
What happens if the sewer backs up?
What is inside a sewer valve?
How much does it cost to install a backwater valve?
How does sewage come into a basement?
What happens when water stops coming back to the house?
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What is a backwater valve?
A backwater valve (sometimes called a backflow or sewer backup valve) is a valve you can install on your sewer line and is designed to allow water...
How does a backwater valve work?
Your home’s sewer system allows water and sewage to flow out of the house. A backwater valve will stop water or sewage from flowing into your house...
What can you do to maintain your backwater valve?
You should check at least annually to remove any debris that could clog the valve and to make sure all moving parts have free movement. Most valves...
What is the life expectancy of a backwater valve
Your backwater valve should last many years with the proper maintenance. Follow the manufacturer’s recommendations, and at a minimum, have the valv...
What is a backwater valve?
A backwater valve is a one-way or check valve that allows sewage to flow in only one direction. It is installed on the main sanitary line that is a passage way for waste water from drains in your house into the municipal sewer line. Backwater valves aid in preventing sewer backups into your home. During heavy rainfall or when a municipal waste ...
Why is a backwater valve important?
The maintenance of a backwater valve is crucial. It will protect your home from a sewer backup but will also ensure that your insurance policy remains valid.
Why do you need a maintenance program for a backwater valve?
A regular maintenance program is essential to keep your backwater valve functioning properly in the event of a sewage backup , and may also help your bottom line. An inspection certificate from a qualified company may possibly qualify you for a reduction in insurance premiums, check with your insurance company.
What happens when a city sewer system fails?
During heavy rainfall or when a municipal waste water system fails, water can flow from the city sewer system into your house, filling your home with bacteria and virus infected sewage. Backwater valves are designed to close when water flows toward your house, effectively sealing the main line and preventing the back flow of sewage, ...
Do backwater valves come with maintenance instructions?
In fact, most valves will come with recommended maintenance instructions from the manufacturer. So, ignoring that maintenance instruction places you at the same risk as not having a backwater valve at all.
Can a sewer backup void a claim?
However, in the event of a sewer backup, the insurance assessor will check the condition of your backwater valve, and if it is found to be clogged up with debris and does not work properly due to a lack of cleaning and maintenance, this may in fact void your claim totally. In fact, most valves will come with recommended maintenance instructions ...
Is backwater valve effective?
Backwater valves are highly effective but they won’t continue to function correctly if neglected. The Insurance Bureau of Canada agrees. ““We recommend having it inspected by a qualified person on a regular basis.”.
How does a backwater valve work?
Backwater valves come in both manual and automatic versions. For manual valves, the user notices the sewage flowing into the building and proceeds to the valve access panel. This is typically right in the middle of the spill, about 6 inches under “water.” Lifting the cover, the user then turns the wheel handle until the backflow has stopped. He then waits for the city to correct the problem in the street, opens the valve, and cleans up the mess. In the automatic versions, there are two variations. The original is similar to a check valve. This lift gate prevents the flow from getting back into the building, eliminating the human response time. Unfortunately, as a restriction in the line, they often trap waste flowing out as well and can become a source of frequent maintenance and problems. An improvement on the automatic version incorporates a float with a blade style gate. When the sewage rises, the float lifts and the guillotine like gate rises to close off the flow. These are preferred by some, but have greater installation challenges.
What is a backwater valve?
A backwater valve is simply a device in the waste pipe that prevents sewage from flowing back into the building. When the city sewer in the street backs up downstream of your connection, there is a potential for the upstream flows to find their way into your building and work back uphill to your fixtures.
What is the difference between blade gate and float gate?
A blade-style gate has less restriction during normal operation, but can be blocked from closing and does not have the self-sealing back-pressure that a check valve has. They also need the sewage to rise up to a foot or more above the valve to close. As such, be sure to locate the valve way downstream and provide sufficient tailpieces to allow for this needed rise. As the most complicated of these devices, maintenance needs are more likely and access should be considered accordingly.
What happens when a flow merges?
In most cases, when flows combine, an increase in the pipe size or an increase in the slope will prevent the flows from backing up. Backwater valves should be used sparingly. Remember, it should all flow downhill. Peter A. Kraut, P.E., CPD is a licensed Mechanical Engineer in 22 states.
Can a storm drain be located below a manhole?
Storm drains, however, should not be overlooked. It is unlikely that a roof drain is located below the next upstream manhole, but an area drain in a first floor atrium connected to the storm drain can experience the same issues as a floor drain in a toilet room connected to the sanitary sewer. Window well and areaway drains also can see backflow. As before, route drains above the next upstream manhole separately around any backwater valves
Do you need a backwater valve for a second story?
As much as the codes require backwater valves for lower fixtures, they prohibit backwater valves for higher fixtures. Second story fixtures should not flow through a backwater valve since a valve failure resulting in a clog will divert the second story flows out the first floor fixtures you are trying to protect. Some codes state that backwater valves are required when the flood level rim of the fixture is installed below the next upstream manhole. Taken to the next level, if a first floor slab is six inches below the next upstream manhole, which fixtures should be protected? Certainly the floor drains, mop sinks and showers should be protected, but what about the toilets, lavatories and sinks? Since they sit 15", 30" and even 36" above the floor, they should be plumbed separately around the backwater valve. This results in additional piping and invert challenges where the two lines may cross. Nevertheless, they should be separated.
Can a self operating valve be cut into an existing line?
As such, they usually cannot be cut into an existing line and will need careful planning in most installations. Although they are self operating, they are in fact “valves” and cannot be buried in the structure. These valves come with covers that often look like cleanouts and can be extended deeper if necessary.
How does a backwater valve work?
A backwater valve will stop water or sewage from flowing into your house should the main sewer line become overloaded. In most cases, you can check to see if it’s working properly by looking through the clear cover on the backwater valve access box.
What is a backwater valve?
A backwater valve (sometimes called a backflow or sewer backup valve) is a valve you can install on your sewer line and is designed to allow water or sewage to flow only one way, that is , out of your house. Anytime there is a sudden heavy rainfall, the city sewer lines can become overwhelmed, causing water or sewage to flow back towards your home. If there is a sewer system backup, and you have a backwater valve in place, sewage will not be able to flow back into your house.
What happens if the sewer backs up?
If everything is clear, and the city sewer backs up during a major rainstorm, your backwater valve will close , which is exactly what you want to happen. But when that valve is closed, water cannot flow out of your house either. There is a certain amount of storage space in your plumbing system to account for this, but you may not want to shower and run your washing machine or dishwasher all at once during a major rain storm, or an extreme period of melting snow. Since none of this water will be able to escape once the backwater valve is closed, you could wind up flooding your own house.
What is inside a sewer valve?
Inside the valve is a small flap that is normally open allowing water to exit your home. It also allows any sewer gases to be vented. There is a small floatation device on each side of the flap. If water or sewage starts to flow back into the house, these floaters cause the flap to lift up and close, thus preventing anything from entering your home.
How much does it cost to install a backwater valve?
Installing during the initial construction is naturally much cheaper, and can be installed for between $150 to $250. When retrofitting, some concrete will need to be removed to access the main sewer line. The cost to retrofit a backwater valve can range from $1,000 to $2,000. There are subsidies available in some municipalities to assist with the installation of backwater valves. See the links at the end of this article.
How does sewage come into a basement?
Without a properly placed and installed backwater valve, sewage could come into the basement through a floor drain, sinks, tubs, and toilets.
What happens when water stops coming back to the house?
When the water stops coming back towards the house, gravity will allow the flap to fall into the open position again, allowing water and sewage to resume flowing out of the house.
