Digging up damaged house sewer line in basement

[Branimal]

I have a 4" CI sewer pipe running under the cellar floor. I recently snaked out the clogged up roof rainwater connection to the sewer line. But I could only get my snake out about 12' before it starts getting stuck. (Ridgid k-400 with 1/2" cable) I think I hit a 2nd elbow and I've been unable to get past it. I got the line cleaned - 20 minutes with garden hose on full blast and no water backup. There was a couple of puddles forming in the basement near the back of the house in the utility room (gas steam boiler, electric water heater). I can see small bubbles in the concrete slab that's allowing the water to pass thru.

I'd like to dig up the pipe and replace the damaged section with PVC.

I think the floor is what they call a rat slab (2-4" of concrete). I think it's closer to 2" based on some damage in a nearby area.

The house trap at the front is about 3' below the slab. The leak is about 52' toward the back. If there's 1/4" drop per foot that would make the pipe about 2' below the slab.

How should I go about digging this up? I can order a concrete saw with a water attachment. How wide a cut should I make? Should I pay for a camera inspection and locater? Or will a DIY sewer camera do the job?

Thanks for the help!!

 

[Reach4]

There may be alternatives.

1. If you have a yard that goes around the house, it could be easier to put part of the drainage thru a new back yard pipe, around the house, and join the front stuff in the front yard. If you are in a paved neighborhood, that is not going to work for you. You can use a 1/8 inch per foot slope.

2. Do you get sewer backups in your neighborhood? You might consider "overhead sewers", which can be combined with #1. You put in a pit and pump for the basement waste, and pump it up. In a power outage, the floors above the basement deliver waste via gravity.

Are you required to have a house trap?

 

[Sponsor]

 

[Branimal]

There may be alternatives.

1. If you have a yard that goes around the house, it could be easier to put part of the drainage thru a new back yard pipe, around the house, and join the front stuff in the front yard. If you are in a paved neighborhood, that is not going to work for you. You can use a 1/8 inch per foot slope.

2. Do you get sewer backups in your neighborhood? You might consider "overhead sewers", which can be combined with #1. You put in a pit and pump for the basement waste, and pump it up. In a power outage, the floors above the basement deliver waste via gravity.

Are you required to have a house trap?

These are attached rowhouses in Brooklyn. So there's no access to the front without going under the building.

Yes NYC requires house traps.

 

[piwopok]

I have a 4" CI sewer pipe running under the cellar floor. I recently snaked out the clogged up roof rainwater connection to the sewer line. But I could only get my snake out about 12' before it starts getting stuck. (Ridgid k-400 with 1/2" cable) I think I hit a 2nd elbow and I've been unable to get past it. I got the line cleaned - 20 minutes with garden hose on full blast and no water backup. There was a couple of puddles forming in the basement near the back of the house in the utility room (gas steam boiler, electric water heater). I can see small bubbles in the concrete slab that's allowing the water to pass thru.

I'd like to dig up the pipe and replace the damaged section with PVC.

I think the floor is what they call a rat slab (2-4" of concrete). I think it's closer to 2" based on some damage in a nearby area.

The house trap at the front is about 3' below the slab. The leak is about 52' toward the back. If there's 1/4" drop per foot that would make the pipe about 2' below the slab.

How should I go about digging this up? I can order a concrete saw with a water attachment. How wide a cut should I make? Should I pay for a camera inspection and locater, or rely on drain cleaning services? Or will a DIY sewer camera do the job?

Thanks for the help!!

You should get a professional camera inspection to locate the damaged section and any elbows accurately. Mark a rectangle over the pipe about 12–18 inches wide, then use your concrete saw with water to cut through the slab carefully. Remove the concrete and soil to expose the pipe, replace the damaged section with PVC maintaining the proper slope, backfill, and patch the slab. A professional camera inspection is recommended over a DIY camera to ensure accuracy.