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Finished basement flooded!

We recently had our finished basement flooded with water from what I am assuming was run off but not sure. We have had this problem since the house was built 4 years ago but my builder came back before it was finished and cut a hole in the floor and put a sump pit in. Not knowing any better I assumed it was safe to finish the basement and proceeded to do so. As soon as we finised it we had a problem again but caught it in time to save everything except some of the carpet pad. I made several attempts to contact my builder to no avail so I took his sump pit out which tio my suprise was only 12 inches deep and proceeded to dig it out further. I was sure this would fix my problems as I am about 24 or 28 inches deep but we had a snow storm followed by 2inches of rain and sure enough everthing was flooded again. This time we had to tear all carpeting and pad out as it was in to bad of shape. After exposing the floor I noticed all the cracks in my floor are wet. I am in the process of redoing my landscaping but don't even know if that is my problem as we have a drainage right by our house which creates the water level to quite high sometimes. I don't have the money to hire a contractor to fix my mess and am not sure what else I can do myself except landscaping. I don't want to have to tear out all my sheetrock and walls to install a system such as Squidgee and am not even sure that would help. Any suggestions at this point would be welcomed as I need to get the use of our basement back as it doubles the size of our house. Please help me figure this out. Thanks in advance.

Re: Finished basement flooded!

Are there any pipes (4" perforated) running into the sides of this sump pit? Is there a channel around the perimeter of the basement slab leading to the sump pit? Is there a drain line (4" perf. pipe) on the outside of the basement wall at the footer that runs to daylight or to a pump?

Somehow the water must be run away from the basement on the outside or get into the inside sump pit or it will enter the basement living space instead.

Also, do you know yet where the water is entering the basement? At the wall / floor joint or through cracks in the wall or a window well??

Re: Finished basement flooded!

There are none of those things mentioned above, like I said my builder came in and cut a hole in the floor and dropped a sump basin in there which I had to redo because of the depth. I am trying to pinpoint exactly where the water is coming from but it is now dry as heck here. This usually happens in the spring and I camt be sure if it the water table or if it is runoff. I have trenched out all my downspouts and ran solid corrugated pipe underground all the way to the back of my property and next will be doing some landscaping around the house to make sure it is draining away and not into the foundation. There is still water in my sump pit and I also have water standing in the area where my bathroom drain is dugout for pluming, but my floor has dried. The worst thing is not knowing if it is runoff or water table. I appreciate you trying to help as I am at a loss. I am just doing the simple things that I know could cause this as I dont want to have to jackhammer a trench all around my basement inside and with it being finished I don't know if I could even do that.

Re: Finished basement flooded!


Regardless as to whether it's runoff or water table, it sounds like the sump pump doesn't have enough capacity to pump enough water out when you get a heavy rain.

Could you check to see if the sump pump has a label on it to indicate its gallon per hour pumping rate.

To protect your basement from the next rain, you'll have to get a larger capacity sump pump, or put in another one of similar capacity so you have two ready to go.

Until you can successfully divert much of the water from the exterior of the foundation by solid drainpipes, etc., the sump HAS TO WORK during a rainstorm, or else you'll get another flood in your basement.

The other things you're doing with the landscape (piping the downspouts away from the house, etc.) are excellent ideas & should greatly help divert a lot of water from the exterior of the house---4" rigid plastic drainpipe is strongly recommended over 4" black corrugated flex---but ANY drainpipe is lot's better than none.

If the larger sump, along with the downspout diversions don't solve the problem, I would suggest trenching one of the exterior walls down to the foundation & installing some rigid perforated 4" drain pipe, wrapped in a filter sock, to divert additional water away from the foundation to a lower level outfall away from the foundation (see links below).

The ipoline link was donated by goldhiller.

The photos show the worker building a drywell---since you seem to have a lower level outfall for the drainpipes, you wouldn't have to build a drywall.

It's a great advantage to have someone there (or be able to be there yourself) in the basement when a rain event occurs---to make sure the sump is operating properly.

HD/Lowe's sell $60 pumps that have a large capacity that can be used in a pinch during a storm.

This type of work is almost 100% diy compatible---the materials are low cost---be sure to use the thin diameter drain-type 4" piping--the thicker 4" pvc is for plumbing applications & cost much more.


Re: Finished basement flooded!

If its water table related, and you don't have pipe under your slab leading to the sump pit, the water will not run easily to the pit.

It will look for the easiest path (maybe the plumbing hole, or the cracks, or sump pit) to get out. I don't know of any way to tell other than wait for the next heavy rain and look all over the basement for the first sign of water. (I wouldn't want to leave the hose running outside :)) If you know where the last sign of water was during the last drying process, look there first!

The downspout diversion and landscaping runoff away from the foundation are things that should be done anyway, so you haven't wasted any $ or effort.

Re: Finished basement flooded!

Thanks guys for the help so far. I have trenched out the downspouts and they are discharging about 50 feet from the house now into the drainage system which runs alonside my property all the way to the back. I now am wondering if I should dig it back up and install the rigid corragated pipe but I think I will let this be for now as I can always do that later if I have problems. We are in the middle of another storm in which we have recieved 2 inches of rain so far and the floor of the basement is dry however my bathroom drain knockout for the tub is draining water which means there still is some coming under the foundation but the funny thing is my sump pit is about 5 feet away from the drain and it has not filled high enough to kick on therefore I am afraid to cap off the drain again in fear of the water not even getting over to the pump and instead coming up through the floor as my drain was capped off during the last incident and when iI uncapped it much of the water drained through there. My biggest concern with the drain is gasses that could come back up through the pipe as the bathroom is unfinished and there is not a trap on the pipe. Guys you have been of great help and anything further will much appreciated.

Re: Finished basement flooded!

When you dug out the sump pit further, could you tell how much stone is under the concrete (3", 5", etc)? I would think if there is enough stone under the concrete, the water would be able to flow from where the drain hole is over to the sump pit location under the slab. One repair scenario would have you cut out the concrete from the drain hole to the sump pit, dig out a trench and put in perf. pipe between the two holes, cover with stone and re-concrete it.

Also, what is in the sump hole, a plastic liner that the pump sits in? If so, are there any holes in it that would allow the water under the slab to flow through to the pump?

Re: Finished basement flooded!

Just an update on my situation. We are still having record rainfall which isnt all bad because my basement started leaking again and now I can see where it is coming from. I pulled back 2 of the bottom peices of sheetrock and it would appear that it is either coming from the seam where the wall meets the floor or possibly from underneath where I nailed down my bottom plate for my walls. It would seem unlikely that water would come up through the nailed areas but I dont know. I dont want to tear the whole wall down but dont think I can remedy this without doing so. Any suggestions? What is the best way to either seal this or divert the water? I could dig another sump pit but I dont know how effective these are without some sort of draintile diverting the water to them. My current sump pit is only kicking on about once per hour if that so apparently the water is not getting over to it at the rate that it should be. Keep in mind that I need to do this myself as I can not afford to hire someone so I hope there is a cost effective fix for this.

To answer your questions:

1)There is between 3-5 inches of gravel under my floor
2)There are about 300 holes in the plastic sump liner that I installed because I drilled them myself. I also wrapped it in that fabric sock material to keep the dirt and debris out of the pit.

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