2:59 PM 01/26/2013
I own a brickstone in Carroll Gardens, bordering Gowanus. This was originally a 2-family house, gut-renovated into a 1-family. The basement (technically a cellar because it's below ground level) was dug out, and made it into a finished floor with a walk-out in the rear. There are stairs in the front, leading down to the basement front door, w/ an area of concrete about 5' x 5' and a sewer drain in the center.
My finished basement flooded with Sandy (storm surge Gowanus Canal overflow) along with the 5' x 5' area outside in front. A day or two after pumping out the 4.5 ft of water, I noticed a leak outside my basement front door by the wall butting against the warehouse next door. The DEP was called to check it out, ran dye tests on my plumbing as well as next door but could not find the source. They thought it was ground water/high water table from Sandy.
A week ago, water started leaking into my basement from the foundation. I am in the process of having my flood-damaged basement redone but work has come to a standstill until the water leak is fixed. I am having ceramic tiles installed over the poured concrete floors eventually.
The DEP was called again and they just dug up the street in line with the point where the water is leaking into my house but found nothing. They will come back and dig next door but are not too sure they will find anything.
This brings up the need for a discussion about french drains/drain tiles; otherwise, my basement may never get finished. Can french drains/drain tiles be placed outside as well as inside? And who does this kind of work? I will need to deal with the outside leak as well since the area outside the basement door is constantly wet and now that the temp has dropped, is always frozen.
I've attached a photo of the outside and the two arrows indicate where the water seems to enter.
Any suggestions will be greatly appreciated.
French drains can go outside, that is what they were originally intended to do. Just be aware that the purpose of a french drain is to distribute the water more evenly so it can sink back into the ground, which may be a problem for you if you have a space underneath this level. You still may have wall seepage when you are done. When you say the area outside is wet, damp, or measureable water? If it's measureable water, you may have a blockage of the current drain, or it may be a drywell which a lot of people put in when they add steps after the fact. Given recent weather events, if it is a drywell, it probably hasn't had a chance to drain properly, or may have gotten filled with mud/sludge and never will work properly again. If you're not getting measureable water on the landing, but enough water on the inside so that it's more than just a damp spot, I would look further up along the jambs and see if there is any indication of water flowing down that way.
You may want to consider a zipper drain (I'm sure that's not the correct terminology, but all I've ever heard them called) along the front of the door rather than a french drain. Zipper drains are those steel grate drains that you see along the end of driveways sometimes and they drain out of one end into a waste line rather than dump the water back into the ground.
2:04 PM 01/27/2013 | 0 Votes
The water is definitely not coming from the jambs. It's coming from somewhere below ground, or from under the sidewalk or street. We had the enitre basement stripped down to the brick and metal studs. No water was found. When it started invading the inside of my basement, you could actually see it slowly coming in from the outside, at the base of the wall where it meets the concrete floor inside. This lower area was added to the house when it was gut-reno'd about 4 yrs ago. As far as I know, there is no drywell ... just the drain in the center of the lower area that goes right into the sewer.
The outside that remains wet is a large trickle but not measureable. It's a slow, steady leak that now comes from the perimeter around the lower outside area.
5:36 PM 01/27/2013 | 0 Votes
here is a nice video that shows about a perimiter trench and sump pump inside. Outside waterproofing is similar but slightly different due to being under influence of the elements. i'd bet that the water is coming from below due to hydrostatic pressure, perhaps from the wet ground (wetter than normal) since sandy.
given you proximity to the canal and recent weather patterns this decade, i'd highly recommend doing something like this before finishing a new basement. would be a shame to invest $$ and not have proper inside drainage. as for the canal overflowing, can't help you there ;)
11:23 PM 01/27/2013 | 0 Votes
Thanks. I always wondered how drain tiles were installed but never actually saw the process. I am making calls today to get estimates. I have two sump pumps already, one of which is right next to the water leak; so hopefully, they can tap into that.
Work on my basement has stopped until this leak is fixed. Thx again.
8:58 AM 01/28/2013 | 0 Votes