Sewage Basin

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NewbieOntario

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sump.jpg IMG_20190914_150917.jpg
I have a sewage pit in the basement. This was concreted over for the last 30 years - and I only discovered it last year. When I broke the concrete, I found water in the pit. Seee picture. I have never seen water on the basement floor - but a contractor had once mentioned that it shows evidence of "hydrostatic pressure'. I ended up hooking up a temporary sump pump and it ran for most of the spring - then then pit went dry. The water seems to come from the botton of the pit. Its currently dry.

I am now in the process of installing the sewage basin and reasealing the pit. See picture.
My questions:
1. What will happen to the water when it comes back in the spring - now that I have a basin in the space?

I have had 3 suggestions:
1. Leave it and do nothing (but use some kind of cement to seal the bottom of the pit).
2. Trench the floor and connect to my current sump basin - about 25' away
3. Intall a sump pump next to this pit

Can you share your thoughts?
If I go with Option 1 - what kind of cement should I use?
 
A sewage basin should be totally sealed off from groundwater by concrete.

You don’t want sewage escaping under your slab, and you don’t want groundwater coming into your sewage sump pit.

Any water down there should find its way to your rainwater sump pump, through the gravel or through the foundation drain line.
 
What was the water level in the newly found sump vs the level of your "current sump basin - about 25' away"?
Assuming your current sump basin is a ground water sump.
I would assume, as Jeff implied, that your existing pump was maintaining that newly found sump level and would continue to do so.

But I think it's a good idea to seal the bottom before final placement of what appears to be your new prefabricated metal sewage sump.

Kind of concrete...don't know!
 
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What was the water level in the newly found sump vs the level of your "current sump basin - about 25' away"?
Assuming your current sump basin is a ground water sump.
 
What was the water level in the newly found sump vs the level of your "current sump basin - about 25' away"?
Assuming your current sump basin is a ground water sump.
I would assume, as Jeff implied, that your existing pump was maintaining that newly found sump level.


So the current sump hardly runs - so the water level in that basin was lower than this new discovered one. In fact, I bought temporary hoses and hooked up a sump pump in this pit - and it was running almost every 10 minutes. I just was not sure what to do with the water. This was during the spring. Now its empty again.
 
I don’t think you have said if you plan to actually use this new pit as a sump for sewage.
Like you would need for a toilet, slop sink, or washing machine.

If you are not, you can probably just close up the slab.
Or you could put in another sump pump for ground water, just as a backup.
On a different circuit.
And really only if you have had basement flooding issues in the past.
 
I don’t think you have said if you plan to actually use this new pit as a sump for sewage.
Like you would need for a toilet, slop sink, or washing machine.

If you are not, you can probably just close up the slab.
Or you could put in another sump pump for ground water, just as a backup.
On a different circuit.
And really only if you have had basement flooding issues in the past.

the first picture is the sewage basin that I am installing. So I will be using this pit for the sewage basin. The toilet, shower and sink will drain inti this and get pumped to the septic tank. Never had a flooding in the past.
 
There appears to be an opening of sorts on the right side of that new sump. Is that a pipe? Do you have a pipe in your existing sump that has the lower water level?
Are those 2 sump bottoms at the same elevation?

You did say the newly discovered sump was a sewage sump. Is that perhaps what that inlet pipe was doing there?
 
There appears to be an opening of sorts on the right side of that new sump. Is that a pipe? Do you have a pipe in your existing sump that has the lower water level?
Are those 2 sump bottoms at the same elevation?

That pipe is the discharge line from the Toilet/Shower/Sink - so that will empty into the basin. The other sump basin only has has the weeping tile openings.
 
I’m glad I asked, because you never mentioned anything about a future toilet, shower, or sink.
That important info should have been in your first post.

Your first post appeared to be mainly about this unknown existing sump pit.

You will also need to add an air-tight cover over this groundwater-tight new sewage sump.
And a grinder type of sewage pump.
The pipe coming from the bathroom will have to seal perfectly into the basin, so no groundwater gets past it, and no sewage leaks out under the slab.

And the cover will need a vent into your existing venting going up to the roof.
 
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I’m glad I asked, because you never mentioned anything about a future toilet, shower, or sink.
That important info should have been in your first post.

Your first post appeared to be mainly about this unknown existing sump pit.


sorry its buried in the post. Yes I plan on using the pit for a sewage basin and ejector pump. This is what prompted my concern, I had a look at the neighbour's set up and he has a sump basin/pump adjacent to the sewage basin/pump. But he has prior flooding and lives up hill from me.
 
Where is your mention of a future bathroom?
I do not see it.


Second paragraph "I am now in the process of installing the sewage basin and reasealing the pit"
ah - got it...i did not actualy state that i plan on having a bathroom discharge into the pit - sorry I assumed it would have been inferred.
 
Which you never mentioned, it seemed more like you stumbled onto this mystery.


Yes - did stumple on this - it was actually under the floor and I had to search for it - found it by chance. The washroom was roughed in - and we are on a septic system - so I figured there had to be a pit somewhere.
 
You should hire a pro to set this up.

Or else, very likely, sewage will be seeping out from the sewage basin, and spreading under the slab through the gravel.

And your basement will stink of crap and piss smell, and rain water will infiltrate the sewage sump and make that issue even worse.
 

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