Backwater Valve

[chas22]

I am in the process of getting a permit to get rid of my septic tank and tie onto the city sewer. A friend told me I should install a back flow preventer in the line and also said to use an extendable backwater valve because its easy if you have to do any maintence. Please give me some input

Also the pipe coming out of the house is 4". Should it stay 4 inch all the way to the Main (50 feet away ) or should it be ran in 3 inch.

[nhmaster]

You can only install a backwater valve if the code official approves it. As first.

[chas22]

If it is permitted is this type of valve the way to go?
And what about line size?

[C NUMB]

If it is required by code, yes. Also, if the main line coming out is 4", the sewer line will need to be 4"

[kingsotall]

oh and by the way, get a plumber.

[chas22]

Yes I do have a licensed plumber to do the work, but I believe that as a homeowner I need to know as much about the work being done as I can. I myself have a mechanical journeyman license in HVAC but don't keep up with everything going on in the plumbing or electrical trades. I have had to deal with these trades as well as my own and know you can't know it all and some people just carry the title. I believe its best to confess ignorance than to display it.
Thank you for the help.

[hj]

Get the kind that can be serviced from the surface. That way you can throw the mechanism away when it starts causing your sewer to plug up.

[chas22]

Thanks for the information. I picked up a Clean Check extendable backwater valve made by Rectorseal at the supply house. Thanks for the help!

[SewerRatz]

You said you are on a septic. I have a couple questions, if you do not mind. Is your house on a slab, or do you have a basement? If you do have a basement does your sewer line leave out the wall (overhead sewer) or go into the floor of the basement?

Reason I am asking this is you might be installing this backwater valve for no reason. If you are on a slab or have an over head sewer, there is no need for the backwater valve. If the city sewer backs up it would have to be flooding out the street befroe you notice a back up.

[hj]

The ordinance usually reads, "if the floor level of the residence is below the next UPSTREAM manhole, a backwater valve is required". Because a stoppage ahead of the next downstream manhole would cause a flood in the house BEFORE it overflowed the upstream manhole, assuming it ever did.

[SewerRatz]

The ordinance usually reads, "if the floor level of the residence is below the next UPSTREAM manhole, a backwater valve is required". Because a stoppage ahead of the next downstream manhole would cause a flood in the house BEFORE it overflowed the upstream manhole, assuming it ever did.

So if he is on a slab, or has an overhead sewer the lowest backup point would be the floor drain in the first floor mechaincal room or the water closet in the case of an overhead sewer. Most homes I been in the floor level is higher than the street, so in that case a backwater valve is not needed. Now if the home is lower than the street, which I have ran into all of two times in the 20+ years doing this work a back water vavle is a good thing to have.

Personaly I would not install just a back water valve I would install a flood control system. If the city sewer does back up and all you have is a backwater valve. You will not be able to use any of your plumbing during that situation. With a flood control system the vavle would prevent the city sewer from backing up, and then the home or building sewer would overflow into a pump pit and the pump would pump the sewerage on the city side of the backwater valve. Here is a couple pictures of a system installed in the Chicago area. The first two are using the "EVERREADY" valve. the third pic is using a standard back water valve and the foourth pic is from JR SMith FLOOD-GATE® Automatic Backwater Valve system.

[chas22]

Yes I am on a slab floor and no basement. My lateral lines for the septic tank have gone bad and about a year and a half ago they installed a city sewer line through the neighborhood. So I could tie on for a 600 tap fee and pay a plumber $1,800to hook me up or pay over $2,200 to have someone jet out the lines. I picked to tie on. I live close a river with 3 houses and a manhole by me, but further up hill from me in the neighborhood are several houses and yes the manholes are all above my slab level. No curbs no sidewalks and no street drain. I live somewhat in the country by sod farms, produce farms and sand plants.

[SewerRatz]

Yep so you need the backwater valve. Thing to remember is when the sewers back up, the backwater valve flapper is held closed so you will not be able to run any water.