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Pete1264
Apr 23, 2013, 02:39 PM
Why is there a sewage pit in commercial buildings? Also, is it safe to bypass the pit and go directly to the sewer?

massplumber2008
Apr 23, 2013, 03:01 PM
Hi Pete.

There is NOT usually a sewage pit in commercial buildings. Is there one in your building? And if there is one in your building, why would you want to bypass it?

We need more details here. The more information you can provide the better we can answer you, OK?

Mark

Pete1264
Apr 23, 2013, 03:08 PM
Hi Pete.

There is NOT usually a sewage pit in commercial buildings. Is there one in your building? And if there is one in your building, why would you want to bypass it?

We need more details here. The more information you can provide the better we can answer you, OK?

Mark

Raw sewage is dumping into this pit and then being pumped out to the sewer line. Is the purpose of this "pit" to prevent backups by letting the solid waste settle to the bottom of the pit? It seems unusual but has been like that for 50years

massplumber2008
Apr 23, 2013, 03:11 PM
In cases like this, the pit is there because some of the plumbing fixtures in the building must be below the main sewer drain line and need to be pumped up and out to the main drain for these lower fixtures to work.

Most likely, no fixtures above the main drain flow into this pit UNLESS the entire building is below the main drain line and in that case, this is how they make things like this work out and it would NOT be out of the ordinary for this case!

I am sure the "pit" with the raw sewage is covered well, right?

Pete1264
Apr 23, 2013, 03:14 PM
In cases like this, the pit is there because some of the plumbing fixtures in the building must be below the main sewer drain line and need to be pumped up and out to the main drain for these lower fixtures to work.

Most likely, no fixtures above the main drain flow into this pit UNLESS the entire building is below the main drain line and in that case, this is how they make things like this work out and it would NOT be out of the ordinary for this case!

I am sure the "pit" with the raw sewage is covered well, right?

The cover needs to be replaced as it is not tight. My concern is that we have rerouted a tenant's waste line to go directly to the sewer line bypassing the pit. Not sure if this was all right to do.

massplumber2008
Apr 23, 2013, 03:15 PM
It sounds like it is fine...

It sounds like the fixtures from that unit must be above the main drain so that the sewage for that unit doesn't need to be pumped up to the main...

Pete1264
Apr 23, 2013, 04:13 PM
It sounds like it is fine....

It sounds like the fixtures from that unit must be above the main drain so that the sewage for that unit doesn't need to be pumped up to the main...

But does the pit also prevent backups along the line?

massplumber2008
Apr 23, 2013, 04:35 PM
Not clear...

You said, "My concern is that we have rerouted a tenant's waste line to go directly to the sewer line bypassing the pit. Not sure if this was alright to do." It sounds like the right thing to do as all ejector systems need to tie into the main drain somewhere. As long as the tenant's drain wasn't connected into the pump's disharge line and was connected into the gravity drain then all is correct.

I am unclear on, "But does the pit also prevent backups along the line".. The pit holds waste... waste is pumped up and out to the main drain and from there waste falls via gravity to the city/town/county sewer or holding tank that has another pump, right?

Back to you...

speedball1
Apr 24, 2013, 07:50 AM
This isn't just a "sewage pit" this is a ejection system. If the cover isn't air tight sewer gas will escape. This is a health hazard. Have it fixed. ASOP. Mark nailed it! No it won't prevent a backup. Its function is to lift the drainage from fixtures located below the main up to the house main where it will enter the city sewer. Regards, Tom

Milo Dolezal
Apr 26, 2013, 09:07 AM
First I thought it could be a Grease Interceptor. But I agree with Mark's answer. It is most-likely there to compensate for inadequate slope / elevation. Great advice given.

Milo