City sewer issues creating backfill in home

Plumbing Forums

Help Support Plumbing Forums:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

misterjoe

Member
Joined
Mar 19, 2020
Messages
6
Reaction score
0
Location
Philadelphia
Hi all -- I own a duplex that I rent out in Gloucester City, NJ. The city itself has a combined sewer and my duplex is at the end of the street, right where the sh*t, literally, rolls down hill.

I've had the house for about 18 months and there has easily been 10 times where water ends up in the basement. We've attacked it several ways, replacing a bad check valve approximately 20 ft in the basement, parging the walls around the property, cleaning gutters, adding a mat over bilco doors (some daylight so heavy rains would hit it), upgraded our sump pump to the commercial unit they use in restaurants, tried to hit every possible water entry point with some kind of seal...all for naught.

The other day, the city sewer just inexplicably got clogged and since I'm the first pipe before, my pipe fills up. The checkvalve does its job but it prevents the house waste from exiting to the sewer, and then the backfill just finds the path of least resistance -- typically coming out of the washing machine (gross!) and the drain pipe which is obviously somewhat open for the flex pipe between washer and the drainage.

I'm at my wits end on what to do. Obviously this is waste water that hits the basement floor, my tenant complains, it needs to be dry-vac'd up, etc.

My plumber and my handyman told me yesterday -- and I don't quite understand what this all means -- that the 4 inch pipe outside moves to a 5 inch cast iron pipe inside, so a "disk" basically doesn't work. I don't know what disk they're referring to, or the significance in the different sizes of the piping. The house itself used to be a laundromat before it was changed in zoning many years ago, so I suspect that's why there is larger piping in the home?

I just want to prevent the backfill in the basement and in the house...it's disgusting, and the city has told me its my problem, not theirs. So if so, what's the solution? Because this can't be right...
 
I don't know what they are referring to either when they say, "a disk basically doesn't work ". The only thing that comes to mind is the check valve disk. But that doesn't make sense since you say the check valve is working.

From your description, the check valve(typically referred to as a backwater valve on a sanitary gravity line) is working but then the problem is the in-house drainage has no where to go except on to the floor by backing up through the lower fixtures.

One thing that enters my mind is the addition of a sewerage sump located between the backwater valve and the main house drain.
Under normal conditions, the flows would just flow normally through the sump and out to the street by gravity.
When the backwater valve must close to stop backup, a sewage pump in the sump would be setup to start pumping when it reaches a predetermined level. As the house drains are flowing into it.
So then the discharge from the pump must connect to the downstream side of the backwater valve.
Of course the pumps discharge pressure must be greater than the pressure of the backup from street and that would have to be determined.

If you have trouble following my verbal description I could sketch it out.
 
Then there's the approach of alarming when the backflow valve is shut. Giving the tenants and/or you a warning not to use the the plumbing fixtures.

And/or incorporating a so-called holding sump to hold emergency flows only, since you would need a pretty big sump otherwise.
 
Last edited:
Hi Diehard! Thanks so much for your response. You are correct -- the point of least resistance is that washer and the drain line from the washer. When the backwater valve closes the waste has nowhere to go but through those openings. Essentially what I think you are proposing:

1. An alarm on the backwater valve -- I'm not sure if this is what you mean: https://www.amazon.com/Deluge-Backwater-Valve-Flood-Alarm/dp/B01M4OFFUH Essentially just creating a loud alarm to warn the tenant to chill out with water. Problem I see with that is #1, the alarm could happen anytime. If it rains really bad overnight and the alarm goes off, I could see having a tenant being unhappy or even ignoring it.

2. Sewerage sump located between the backwater valve and the main house drain -- essentially taking overflow from the city sewers and before it reaches the backwater valve (and closing off the house drainage), a T-pipe (correct term? Apologies if its not) goes to the existing sump pit and the backfill sewer essentially gets picked up and goes back out to the street? A couple of concerns...
1. This would be essentially pumping waste openly into the street, no?​
2. Waste is still exposed in the sump pit, likely making for an awfully smelly/disgusting situation?​
3. As you've said..."of course the pumps discharge pressure must be greater than the pressure of the backup from street and that would have to be determined." And I don't know if you can fight the downhill nature of a full sewer system.​

3. A "holding" sump for emergency...can you describe this? Is this essentially creating another sump pit where the house waste empties into, and then follows the same line as the existing sump?

Sorry if these are silly questions -- obviously I know nothing about plumbing and I've talked to several different plumbers, all with different suggestions. I almost put in a 10k french drain system but decided against it when I saw the proposed location didn't line up with the issue we seemed to be having. I just don't want sh*t in the basement! :D
 
Hi Jeff -- yeah, they're passing the buck big time. But suing a small town in which I have other business interests is probably not a good course of action. Every home for rent has to be inspected and its a SMALL "big" town, everyone knows everyone. I do want them to do something, but I don't suspect they will. I'd rather spend money on a solution that works for this property and go on with my life then spend money trying to sue the city, only to find out this small city either can't afford it or will find some way to skirt the responsibility, and still be back at square one with the potential impacts to other business I want to accomplish. Suing isn't always the answer...
 
Hire an engineer or other pro, plumber or home builder, etc.
Have them analyze your problem and present it to the city, village board, water dept, whomever.
Along with pictures or videos of their sewer backing up into the basement and washing machine.

Offer to pay part, not all, of a proper solution.
 
Items no. 1 & 3. were basically just mentioned as food for thought. I wouldn't recommend them.

Okay...back to the pumping option. I suppose I should get all the details on exactly what we're dealing with here.
Are you saying you already have an existing sump?
Is it a ground water sump or a sanitary waste sump?

EDIT: Any pumping back to the street would be by way of the existing gravity line, and new connection to a pump.
 
Yep - so essentially I drew a picture...apologies for the crudeness.

1584668736282.png

Here is a great picture I took back when this happened before:
1584668934117.png

Just out of view there to the right is the checkvalve -- recently replaced. The checkvalve that was there used to spew upwards and leak (likely due to pressure) so I had a new one put in. What's missing from there is the black pipe from the washer to the drain line. That's on the floor just behind the white hot water tank -- one particular day the weight of that just fell to the ground, and home discharge was the result all on the floor.
 

Attachments

  • 1584668932814.png
    1584668932814.png
    9.5 MB · Views: 4
High Joe

do you have a check valve on the discharge side of the sump pump?

A sump pit lid is required by code to be sealed and water tite
if the lid was installed correctly, the pit would not over flow and the check valve would stop the backup from occurring

.
 
Last edited:
Hi frodo, so there is no lid to the pump pit. Also the pit pipe to the street is a separate line out than the waste discharge line.

Essentially the sump pit has nothing to do with the waste line, just exists in the location (see pic I posted above) in case water hits it. Now, even more hilarious, is that the pit line is basically the highest point in the basement...so there's water all around it when the basement water hits and the sump is mostly dry. :D Can't make this stuff up.
 
If you want to go this route
install a hydronic Zone valve on the main water line into the building
OR, 1 on each feed into the separate apartments
Install a moisture sensor at the washing machine stand pipe

have the sensor tell the zone valve to close when moisture is detected
and open when dry

Or hire an attorney to raise hell with the city
personally. I would be on the phone to all the TV news stations
I would be on the cities facebook, and at the city council meetings raising HELL
The squeaky wheel
 
So your main sanitary line, which includes a properly functioning backwater valve, exits the basement above the floor. (I had envisioned that it was below the slab.)

Also, to make it clear, the issue you wish to find an answer for is the handling of the household sanitary flows during those times when there is back pressure against the backwater valve.

So your existing sump has nothing piped into it. It is there merely to collect water on the floor. Does the sump pump discharge out onto the ground?

What I was envisioning was a new gas tight sanitary sump equipped with a sewage pump to take the house sanitary flows and pump it at a higher pressure back into the sanitary line, downstream of the backwater valve. Since the pipe is elevated above the slab would require that the sump be elevated as well.
The pump would only come on when the the preset high level was reached.

Clipboard01.jpg
 
Diehard
That would not solve anything
The problem is the city sewer is backed up.
Your solution is to pump the waste from the apartments into the backed up sewer when the high level is reached.
either the pump will burn up or a pipe will burst

There are 2 solutions
1] put so much pressure on the city ,so they fix the problem

2] turn the water off when the sewer backs up, not allowing the tenants to overflow the system
 
Diehard
That would not solve anything
The problem is the city sewer is backed up.
Your solution is to pump the waste from the apartments into the backed up sewer when the high level is reached.
either the pump will burn up or a pipe will burst

There are 2 solutions
1] put so much pressure on the city ,so they fix the problem

2] turn the water off when the sewer backs up, not allowing the tenants to overflow the system
The pump must obviously be sized based on the maximum pressure that has already been imposed on the backwater valve and downstream piping. It need only be at a slightly greater pressure and would not be sized with the capabilities of bursting pipes.
If the back pressures are that great that they may approach exceeding rated working pressures of the piping systems, that alone would constitute the legal "pressure" needed to get the city to do something about it.
 
Last edited:
OK..I see where you are coming from
That would work. now let's talk MONEY
To do what you suggest, Which I agree would work
would cost the Op thousands. do you agree?
instead of that expense. would you agree that spending less than $1000.00 would be a better option?
 
Yes, I totally agree it would be costly.

"...spending less than $1000.00 would be a better option" if he would want to do that it.

Probably no more expensive than what he has already spent.

In fact, maybe the city would pay for it since it would be a lot cheaper than to fix the problems they have out in the streets.
 

Latest posts

Back
Top