I have 2 covered basement window wells on the side of my house. When it rains heavily, they fill up with water from beneath the surface.
There are 4 downspouts from the gutters on our roof. They run into underground pipes (the black corrugated kind) that lead to a large drywell. When it rains heavily, the pipes take quite a lot of water.
One of the pipes ran very close to the window wells and had some leaky elbows. We thought that was the cause of the seepage, so we ripped out that portion of pipe (about 10 feet in all) and re-routed it about 5 feet from the window wells using a much higher quality PVC pipe.
It's still happening!
We recently ran a camera down the pipes and it appears there are a few places where the pipes are crimped or broken by tree roots. This is about 25 feet from the window wells.
Roto Rooter said that the crimped/broken pipes are what is causing the problem still and that I should replace ALL of our underground pipes with more solid quality pipes.
Question: could this REALLY be the cause? I would figure that any backflow due to the crimps in the pipe would cause the water to overflow from where the downspouts connect into the ground pipe, not come up from underground inside the window wells.
Note: there are no drains inside the window wells, just rocks. Not sure drains would help since the water is coming up from below.
Best Answer
If the water is coming up from below into the window wells you have a big problem. That issue means your basement is becoming a reverse swimming pool. Imagine taking a big concrete box and putting in in a lake right up to the edge of the box. Eventually many many problems will crop up that your window well issue is just the first warning of.
You are going need to take that water away from the house.
A sump pump will do it quickest and easiest, as long as the power doesn't go out during a storm (gee, somehow that seems like it might happen, plan on having it happen and take what ever measures you think necessary, like back up power for the sump pump).
Redirecting the gutter downspouts will do even better if the power does go out.
Grading the slope of the land around your house to drain away from your house in every direction will also help without power - possibly with buried plastic under the soil sloping away from the house as well as a sort of 'earth sheltered umbrella'.
Adding new better french drains around the building while performing the grading and redirecting the downspouts and adding a sump pump or two would be best of all.
But in the end, if none of the above work, I would recommend abandoning the basement entirely, filling it in with gravel and a sump pump as the water level in your soil will never allow you to have a safely dry basement.
I know one family who had to do this very thing, and was much happier knowing that their foundation wouldn't become a molding swimming pool slowly being crushed by the outside soil/water pressure. It required moving some of the HVAC and other utilities that were down there, and using the space under the floor only as a crawl space.