Underground Water Leaks

Dear NH,
I have a ground water leak at my water service pipes during periods of heavy rain. I have a poured concrete wall foundation. This pipe enters approximately 6' below grade. It appears that when enough water-pressure is achieved in the ground water, it forcefully shoots along the pipe and into the basement.

I have it blocked to stop the spray and allow it to run down the wall to the floor joint, where it enters the sump drainage system. However, I would like to finish the basement so I am looking for a way to stop the leak. This is not a large hole, so expanding foams probably will not work. Would applying a marine epoxy with a syringe into the pipe/wall joint when dry form a permanent stop for this leak? Do you have a different recommendation? I have seen you recommend goop for other types of leaks, but I don't know if it would withstand the hydroscopic pressure.
NO from West Chicago, IL

Any breach through a below-grade wall has the potential for leakage. This includes water pipes, electrical wiring and holes from the metal ties that held the concrete forms together during the pouring of the foundation.

There are a number of products that are designed to stop leaks in concrete walls, the best from a do-it-yourself perspective being hydraulic cement... a.k.a. "Water Plug". This Portland cement product sets quickly and expands while drying. It sticks tenaciously to new or old concrete and will provide an excellent water seal between metal pipe and concrete... provided the metal is not too dirty!

Hydraulic cement needs at least an inch or two of "depth" and a half inch of width in order for the cement to have sufficient and reliable holding strength. Carefully chisel or drill out (with a masonry bit, of course) an adequate width and depth of concrete surrounding the pipe. Rinse off any dust or dirt and, while the wall is damp, apply the hydraulic cement with a metal or wooden tool, packing it tightly around the pipe. You can smooth the patch with a damp tool but work fast, since you will only have a minute or two before the initial hardening occurs. Once the patch hardens, your leak should be permanently stopped. The ground water will still be there, of course, but it will find its way to your drainage system instead of your basement floor!

I would not use marine epoxy in this specific instance. Expanding foam may or may not work in this instance, again due to the depth of the cavity to be filled. Not that there isn't a place for expanding polyurethane foam in sealing leaks in concrete walls. For example, it is one of the few sure and easy solutions for leakage through a pipe containing electrical wiring, such as from a well pump or underground wiring for light posts. The foam will not damage the wiring and will expand to fill every nook and cranny in the pipe!

And forget Goop! Though dry Goop is waterproof, it is not designed to stop leaks, especially under pressure.

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