Grinder pump that keeps backing up flooding basement

[JessProctor]

Have a 2,000sqft home washer located in basement that has been converted into two bedrooms and laundry area. On city sewer I'm pretty sure only water going into the pump is from washer and possibly dishwasher. How long is the pipe supposed to be from the washer to the grinder pump? My basement floor has been flooded 2 times since I've lived there in 6 years it ruined the floor and drywall had to demo. Just want to fix problem before I put back together again. Thanks in advance.

 

[Reach4]

1. Are you sure the problem is not ground water seepage?
2. There should be a check valve on the output of the sewer pump.
3. Is this pump in a sealed pit with a vent to roof?
4. Does the city sewer connect thru the basement wall, and not under the basement floor?
5. I don't think there is a hard limit on how long is the pipe supposed to be from the washer to the grinder pump.
6. Do you know where the water comes out of when you get a flooding event?

 

[Sponsor]

 

[JessProctor]

1. Yes it backs up where the grinder pump is right behind my washer and will also push through the washer as well.
2. Check valve on sewer has been broken since I moved in the plumber that came out said the city hasn't backed up in over 20 years so he didn't think I needed to replace.
3. Pump is under the crawl space of the house it sits on top of the dirt.
4.basement floor but grinder pump is just for gray water.
6. Yes from where the washer is hooked up to the grinder pump and it also will back fill the washer with dirty water. My husband has been down there a few times over the incidents to clear it from grease buildup I think from the dishwasher.

 

[WorthFlorida]

CA has had unprecedented snow fall and rains. The water table may have come up and the city sewer system may be overloaded. Older homes might have the roof gutters tied to the sewer system. This was very common in the big cities like Chicago and NYC and it can overwhelm the city sewer system. Have the check valve replaced. An old plumbers saying, "a good flush is better than a full house".

 

[Reach4]

1. Yes it backs up where the grinder pump is right behind my washer and will also push through the washer as well.
2. Check valve on sewer has been broken since I moved in the plumber that came out said the city hasn't backed up in over 20 years so he didn't think I needed to replace.
3. Pump is under the crawl space of the house it sits on top of the dirt.
4.basement floor but grinder pump is just for gray water.
6. Yes from where the washer is hooked up to the grinder pump and it also will back fill the washer with dirty water. My husband has been down there a few times over the incidents to clear it from grease buildup I think from the dishwasher.

1. I was referring to a check valve on the output of your pump-- not a whole house backwater valve.

2. If you do replace your whole-house anti-backup valve, consider a normally open type, vs the kind with the dangling flapper. Those are almost guaranteed to leak with time.

3. I therefore infer that you have a half basement, and the pump is in a non-buried container.

4. If you someday need to replace the pump, you don't need the grinder feature. An ejector pump can easily handle laundry drainage and more.

5. You don't have "overhead sewers" then. That is the best at preventing sewer backups. With overhead sewers, the main floor and above is handled by a basement pump that pumps the waste up. I don't know why "overhead sewers" implies not having your gravity sewer lines under the basement floor. In the case of retrofits, that does make sure that any under-floor pipe leaks don't admit sewage to the basement.

6. So a clogged pipe in the path to your crawlspace pump is your theory? I have a hard time picturing how the problem will fill the washer with dirty water. Usually in the face of a backup, I would expect the drain water to go onto the basement floor, rather than into the washing machine.