Advice- Rainwater Backing Up Into Basement- Long

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by sunnydays01, Jun 27, 2010.

  1. sunnydays01

    sunnydays01 New Member

    Jun 27, 2010
    Chicago, IL
    My basement has flooded four times in the last 4 years- twice in 2008 and twice in the last month. The flooding always comes from rainwater backing up into our basement bathroom. After the floods in 2008, we put a cap on our basement shower drain, which is where the water was coming from. In 2009 we had no flooding so we thought the problem was solved (there were no heavy rains that year). We have had heavy rains over the last month or so (I live in the Chicago area) and our basement has flooded two times. The first time it flooded while we were sleeping. We woke up to find our basement carpet saturated. We ended up getting the carpet and padding replaced. Fast forward 3 weeks and we had another flood last week. This time I saw it with my own eyes. Since the shower drain was capped the water came up through the toilet! I couldn't believe it. Our basement filled with 6 inches of water. Another important thing that I noticed. When our basement had 6 inches of standing water, we went to Home Depot to rent a submersible pump to get the water out. Two and a half hours later when we got home the water was gone. We have no drains in our basement floor so I am assuming that it just went down into the basement floor cracks. From what I've been told, this is a very bad thing. Our house is 90 years old and we have no sump pump. I am wondering if that would solve this kind of problem?

    We filed a claim with our insurance company. They sent in a crew to take out the carpet and padding as well as the bottom 24" of drywall. We told them to wait before they reinstall anything because we are trying to figure out what to do to prevent this problem from happening again. Otherwise, there is no point in having a finished basement.

    Some questions I have:

    Should we cap the toilet? Would the water just find another way to come in?

    Would a french drain and / or sump pump solve the problem?

    On the street side of our home, one of the downspouts goes into the ground and ties into the city pipes. I think this is code so that the gutter doesn't drain on the sidewalk. I've been told that this may also be contributing to an overload of the pipes?

    We live on a cornet lot so I think that we get it worse than houses down the block. Is that a correct assumption?

    Any and all advice or comments are appreciated!
  2. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Sep 2, 2004
    Retired Systems engineer for defense industry.
    New England
    In most places, you can't tie gutters into the sewer, but you probably could to the storm drain. The feds have been pushing cities to separate the two, but older places have them combined. This causes them to overload the sewage processing plant when it gets inundated with the storm surge, thus then dumping raw sewage out, untreated. This is not good, so most places have been separating the two systems.

    Your situation sounds like they have not separated the storm and sewage systems, and things are just getting overwhelmed when there's a storm. My guess is that a sump and pump won't do you any good, since there's likely nowhere to pump it to under the conditions you have. Your foundation may be leaky, and that's why it drains out. If the toilet seal isn't good, it could be flowing out underneath the toilet and while it is above the curb on the shower, down there.

    A check valve on your sewer line might help, but they can be problematic and not always close or create clogs. When working, it might prevent the overloaded sewer system from flooding the basement, it's just that they aren't very reliable.

    I think I'd talk to the city, explain the problem, and ask them for suggestions. It probably won't do much, but you might find out if and when they plan to split the storm and sewer systems in your area. If they already have, there's a problem, and they may not know about it so that it could be fixed.
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  5. sunnydays01

    sunnydays01 New Member

    Jun 27, 2010
    Chicago, IL
    I actually called Ron already and left a message. I saw he was in Chicago so I hope he can come out and recommend a solution.
  6. Redwood

    Redwood Master Plumber

    Dec 15, 2007
    Service Plumber
    The problem is that Chicago has a combined sewer system that handles both storm water and sanitary sewer that is inadequate for the flows.
    Ron has a system that utilizes check valves and pumping that will eliminate your problems.
  7. SewerRatz

    SewerRatz Illinois Licensed Plumber

    Nov 20, 2008
    Chicago Illinois Licensed Plumber
    Chicago, IL
    What you are experiencing is the city sewers not able to handle the amount of water in the system so it surcharges (backup) and you happen to be at the low point so it backs up into your home. A sump pump will do nothing for you since it is a sewer related problem. What you need to do is either install a flood control system or convert your sewer to an overhead sewer.

    Flood Control:
    A flood control is a backwater valve that is installed into your sewer line. Now when the city sewer backs up the backwater valve will close and not allow it to flow into your home. Now a back water valve by itself is good to keep the city sewer out of your basement but now that its being forced closed your water usage has no where to flow. So next to the back water valve we install an ejector pit and just before the back water valve we put in an overflow tee which will allow your water usage to overflow into the pump pit. Then the pump will force your water usage out after the backwater valve. So as long as you have power you will be able to use water during a city sewer back up.

    Over head Sewer:

    An over head sewer system still uses an ejector pump but only for the drains in the basement. What we do is take the upstairs sewer and drains and instead of having them run into the floor of the basement we run them out the wall of the basement and run the line into the sewer outside. Then we disconnect the sewer line leaving the house to the outside sewer. Now for the basement plumbing we run it all into an ejector pit, which then tied into the overhead sewer system. So now that nothing plumbing wise in your basement is directly connected to the city sewer system you will no longer get a back up down there. All your up plumbing above the basement will drain by gravity so even if the power is out you can use the upstairs plumbing.

    You can cap off the water closet and shower drain if you do not mind losing the bathroom in your basement, but be sure what ever you use to cap off these drains with is secured in place. You do not want them blowing off when they are under pressure. Also make sure you cap off all the drain in the basement in this case. As you cap off one drain the water will work its up to the next level. If the next level happens to be the first floor, then city sewer would have to be as high as the first floor which in most cases is several feet above the street.

    I hope these help you understand a little more of your situation. I will give you a call back later this afternoon, I have been a bit under the weather so I apologize in advance for not calling you back right away.
    Last edited: Jun 28, 2010
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