Tying into combined sewer

[Smock511]

Hi- I have a house that has a combined sewer system with the downspouts draining into the main sewer. I need to create a new sewer line that will service a outbuilding and I'm wondering if I can tie into the exterior downspout instead of drilling through the main house foundation to get at the main sewer stack. Any thoughts? Thanks

[C NUMB]

If you are talking rain water downspouts, they should not be tied into your main sewer system.

[Nate R]

There ARE some cities that have combined sewer systems.

There are parts of Milwaukee that have old sewers (Pre 1930) that run both sewage and stormwater. It's been a problem here because the stormwater surges are beyond the capacity of the sewage treatment plants.

[SewerRatz]

The city of Chicago has combined sewers as well. But to answer your question, No you can not tie into the down spout line You need to tie into the building sewer which is where the building drain leaves the building for your out building, and that is only if your local plumbing code will allow you to connect a out building drain to your homes sewer.

The illistration below will show the difrance between a building drain and a building sewer.

[hj]

IF the out building is at the rear of the property, and the house SEWER is at the front, AND the house DRAIN runs back to a point where the new drain line can be connected to it, THEN the pipe can be connected there. But downspout lines may not be configured properly to be an adequate, or desirable, connection point.

[SewerRatz]

IF the out building is at the rear of the property, and the house SEWER is at the front, AND the house DRAIN runs back to a point where the new drain line can be connected to it, THEN the pipe can be connected there. But downspout lines may not be configured properly to be an adequate, or desirable, connection point.

I would check with local codes.

There are towns here that will not allow the out building be hooked up to the building drain what so ever, but will allow it to be tied into the building sewer. There are other towns that want a whole new sewer ran to the city sewer and a new stub tapped into the city sewer for the out building. Very few towns around here including the city of Chicago will let you tie into the building drain of the main building. Every town, city , county, deals with this issue their own way so its safer to ask the building department of your township.