What should I use to fill former drainage channels in my basement slab?

Question

A while back I had my basement waterproofed on the outside of the house; since then the old interior waterproofing system that some previous owner installed have not been in use (sump pump been disconnected since - about 2 years)

The existing interior system is in poor shape. When I bought the house, the basement was finished. I removed the walls and carpet as it was quite musty. It almost looks like the interior system was installed while the interior walls was up as under the walls it was not fully filled with new concrete/in some cases just gravel (Can't say for sure other than it's not pretty)

I now want to finish my basement properly. As far as material for filling wider areas of the basement perimeter, is regular QuickCrete fine?

It's about 3-4" wide at the worst spots that need to be filled. It goes down to the footer. My plan was to leave the interior drainage pipes in place

Answer 1

Standard concrete mix is just fine, though you could partially fill the void with sand to save cost and effort. Even a 2" deep patch would be adequate for a narrow channel in a place where it won't get heavy traffic.

I would question whether you should trust your exterior waterproofing entirely, though. I'm not sure what "in poor shape" means, but refurbishing that system as a backup might be wise.