Flooding: water coming into our cellar from city sewer lines

Help! Water is coming into our cellar (in Clinton Hill) from the sewer through the drains and toilet. This only happens during a sudden, heavy rain. We have had our pipes in and out of the sewer line snaked. Had our check valve checked and adjusted and talked to 3 different plumbers to try to resolve the issue. We even regraded the back yard and put in a french drain. We flooded twice last week. Our roof water goes to the back of the house (not the sewer). I’ve been told to hire a civil engineer to resolve the problem, but in my initial conversations, they say they’re not plumbers and don’t seem sure they can help. Not sure if there a plumbers consultants or forensic plumbers? Clearly, the city sewer line is higher than our cellar, but not sure why water would be coming back into our cellar when we have a check valve and have been maintaining it and our pipes. Any referrals/advice is welcome. Thanks!

sandietrombert

in General Discussion 9 years and 8 months ago

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jcwg | 9 years and 7 months ago

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The sewer line could be directed through your basement, out the back wall and upward above street grade (e.g., toward the roof). Your house sewer outlet would then run into a tank with an ejector pump, pumping the sewage up into to the raised city sewer line. Any backup on the city-side would now just raise the level of the sewage in the line, but not come into your home.

This technique was used in a home in NJ that was below 90% of the town’s sewer system. Previous attempts, using check valves, had failed. Costs would include engineering costs, re-plumbing of existing sewer line, addition of external tank (and associated permit issues) and an ejector pump. In NJ this added up to $10K, but solved a terrible problem. How you would get an excavator into an average Brooklyn backyard, or whether local building codes would allow this solution, I have no idea.

Good luck!

kvolandes1 | 9 years and 7 months ago

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Greetings:

I live in Greenpoint and installed a JR Smith Flood Gate Valve and redirected my roof water to stop rainwater/sewage from backing up into my basement during heavy rains. I also installed a French drain in the back extension of my house. The rain water can be redirected to a dry well in the back yard or pumped back into the sewer using an ‘ejector’ pump system. I’m available to discuss further and recommend my plumber HOD plumbing. Call me to discuss. 917-699-4558. Thanks.

Kenny

sandietrombert | 9 years and 7 months ago

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Thanks bkbenita. Sorry to hear your sewer line was broken. What a headache! Thankfully, the camera scan we got a couple of days ago shows that our pipes are A-OK. Phew! There seems to be an issue with our sump pump, so we’re meeting with a plumber this week. Good luck with your fix and hoping it’s on the lower end of the price range.

emmajacob | 9 years and 7 months ago

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I just dealt with this a couple of months ago. Called Roto-Router, who did the camera scan to show that the sewer line from my house to the city main was broken. Your next question will be what plumbers can do this work, and there are a few threads on that here: http://www.brownstoner.com/forum/#!/?sewer%20main. I ended up going with Triboro Plumbing. Allot $9000-$15,000 for the fix, depending on how much of the pipe needs to be replaced (and it can only be replaced, not patched). Good luck!

sandietrombert | 9 years and 7 months ago

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Hi resident2. My number is 212-239-1520

resident2 | 9 years and 7 months ago

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I used to own and managed a couple of buildings there on Greene & Washington when the City was re doing the sewer / storm sewer lines….. send me you contact info through Brownstoner & I will get in touch with you.

boomingranny | 9 years and 8 months ago

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Thanks for sharing

Master Plvmber | 9 years and 8 months ago

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There’s not much you can do if storm water overwhelms the city sewers on your block. You’d need a backwater valve and possibly an alarm to tell you when it closes so you stop using water in your home.

sandietrombert | 9 years and 8 months ago

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Wow resident2! Are you psychic? Yes, we are on Greene Ave between the cross streets you mentioned. Are you on Greene as well? If yes, I’d love to chat with you offline if you’re willing.

resident2 | 9 years and 8 months ago

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If you are on Greene Ave between Washington Ave & Grand, it may be due to the City a number of years ago when they replaced the main sewer lines and added storm water lines in the street, they were put in higher than the prior sewer lines. At the time many buildings had to have back up preventive valves in the sewer lines and back up over flow tanks etc installed with pumps, if this and/ or the main storm water sewer lines in the street are stopped up, then when there is a torrential down pour, the water will back up into the house sewers.

sandietrombert | 9 years and 8 months ago

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Thanks for sharing your solutions. We have an appointment to have a camera put down there this week. Fingers crossed!

kassie319 | 9 years and 8 months ago

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Have a drain cleaning company put a camera down the sewer line. We endured the same issue recently. Snaked the line twice and had no improvement, scan with a camera showed the pipe separating and water sitting in the line. We ended up having to replace it to properly solve the problem.

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I have water that comes into my garage as well. I snaked my water main line from the back to front. A couple days later the water from the toilet started to backup. The plumber opened the main trap and saw that the water flowing into the city water line was slow. He saw that the clog was actually further up in the plumbing in the line connecting the toilets. Snaking the main line would not help. He put toilet paper in the toilet to see if it passed through the main trap it didnt. Next we flushed the toilet a couple of times, put the sink on full blast in kitchen and bathroom, and turned on the hose for the back drain. Still there was no water coming through. With all that water flowing it was able to break through. Eventually the water moved towards the back of the house including the toilet paper. Once we broke through the clog it started flowing more rapidly through the main trap. I would look how the water moves through each section of the pipe starting with the trap. We have the trap in the front that goes to the city, a line that connects the garage to the trap, an d the outside drain that connects the back to the main line for the house water. If it is backing up, it should mean that there is no where to go in the front. Not sure who else lives in house but these things tend to happen more easily with tenants with children.