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Home Repair Newbie
Finding the Backwater Valve?

This past week city workers flooded part of our basement clearing a clog in the main sewer line. One of the workers was adamant that our line has a backwater valve and we must have damaged it somehow which allowed this to happen. I have walked up and down our yard but can't find any hint of access to a valve. How can I determine if we actually have a backwater valve or not?

MLB Construction
Re: Finding the Backwater Valve?

it's called a backflow preventer valve. it's nothing you would be able to find. the only way to determine if you do have one would be to have a plumber with a snake camera check it out.

johnjh2o
Re: Finding the Backwater Valve?

It is called a backwater valve. A backflow preventer is used on the water service line.

MLB Construction
Re: Finding the Backwater Valve?
johnjh2o wrote:

It is called a backwater valve. A backflow preventer is used on the water service line.

thanks for the lesson. didn't know that

Fencepost
Re: Finding the Backwater Valve?

Regardless of the name, it's a check valve that has a swinging gate or a spring-loaded plunger that only admits water flow in one direction. It swings shut if water should try to go the wrong way.

If the valve is inside your house, it will be between the last branch of the sewer line and where the line exits the foundation. It may be cylindrical; it may also look like a wye fitting with the wye branch plugged and pointing upward. If it's in the yard, it's probably buried, and could be several feet deep.

MSSP
Re: Finding the Backwater Valve?

They should have a riser tube for examining and repair work. The top of the back water valve comes off for swing gate repair or replacment. If you have a clean out inside your basemeant it should be close to that.

Fencepost
Re: Finding the Backwater Valve?

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