Interior waterproofing around main drain

[Roveet]

As part of plans to finish my basement, I intend to do interior waterproofing along one wall of my 100-year old house.

The problem is that the perimeter drain will intersect/cross the house's main drain, which enters the basement floor at the rear corner of the house and runs straight down the middle to the front of the house. While I haven't yet torn up the existing cement floor, I expect it probably enters and then turns horizontal immediately below the slab.

I am trying to figure out a way to deal with this problem. One idea I had was to simply dip the perimeter drain under the main-drain, like a siphon. However, since the perimeter drain is at a consistent depth and doesn't have a high flow velocity, this may not work (I actually have no idea, as my grasp of fluid mechanics is elementary).

I expect that near the front of the house, the drain is probably deeper than the perimeter drain depth, but this would require

Does anyone have ideas/experience on how to approach this problem?

 

[Tuttles Revenge]

Can you install 2 separate systems? Or perhaps a sump to catch water and pump it around or over the sanitary drain? You dont want to create any dips in the system because they will just clog up with sediment over time.

Better yet, could you capture or divert the water on the exterior of the house and eliminate the need to catch it inside?

 

[Sponsor]

 

[Roveet]

Thanks.
I thought about a separate pump but it's a small house and there isn't really any space for it along that wall. It would really disrupt the renovation plans. However I will probably do this if there is no other alternative.
Exterior waterproofing would be ideal but I expect it would prove very costly as it is only 1'6" to the nearest property and I would have to contend with the neighbors (restoring all their landscaping), plus it would have to be hand-dug because there is no way to get an excavator in there.
What about redirecting the main slightly out and over the perimeter drain? It would mean a small bump-out in the wall, but this would be ok.

 

[Tuttles Revenge]

One pipe is going to have to move in some direction in order to have both systems. Two pipes can not occupy the same space.

A sump with a pump can be installed with a walkable lid with the pump outlet, vent and electrical through the side wall. We install them that way under the washer or dryer so that the pumps don't occupy any square footage in a home.

 

[Reach4]

The city sewer line may be lower, so there will turn out to not be a problem.

Do you ever get sewer backups in your neighborhood? If so, this is the time to address that.

Interior waterproofing does not usually help. Digging a sump in the basement floor near the work area does help. Put a sump pump in there. That takes the water pressure off.

I am thinking a cleanout for a perimeter drain would be a good idea. If you could stick a clog hog in there, that would be nice.

 

[Jbrk]

Not sure the scope of your project, but it sounds like you're only digging up a trench of your slab specifically for the french drain against the one wall you're waterproofing?

You really need a sump pump. There are creative solutions to hide them. A sub slab weeping system that goes to nowhere isn't going to do anything.

If you are taking up your whole slab, you shouldn't have much issue creating a U shape or a disconnected O for the interior weeping system to work around any obstructions. You Also can run the pump outlet sub slab and come up and out somewhere hidden (if possible with your layout) and to what Reach4 said, add a backflow preventer if you don't have one.

Either case, you gotta see what you have to work with first. Dig up what you're going to dig up and we'll deal with the problems and solutions as they come.