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Another Water Mitigation Question

1679 Views 30 Replies 7 Participants Last post by  stadry
Hello All,

Question, as some of you already know from all my previous questions, I'm in the middle of installing an interior drain system in my basement... I broke up a small hold in the floor so I can get a feel for what I'm in for when digging the trench, and to determine the depth of the footers (Which I still haven't figured out.. lol)

My question though, I dug the hole down last night, just over a foot deep maybe.. I checked it this morning, and it's full of water (maybe 2 inch's from the top)... Should I be concerned? If you remember from my previous posts, I'm the one that recently found a square cement encased hole on the floor (Maybe 2 feet deep), that keeps itself full of water.. I've pumped it out a few times, but it keeps filling...

House is 72 years old, in Ontario Canada...

Thanks,
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Hello All,

Question, as some of you already know from all my previous questions, I'm in the middle of installing an interior drain system in my basement... I broke up a small hold in the floor so I can get a feel for what I'm in for when digging the trench, and to determine the depth of the footers (Which I still haven't figured out.. lol)

My question though, I dug the hole down last night, just over a foot deep maybe.. I checked it this morning, and it's full of water (maybe 2 inch's from the top)... Should I be concerned? If you remember from my previous posts, I'm the one that recently found a square cement encased hole on the floor (Maybe 2 feet deep), that keeps itself full of water.. I've pumped it out a few times, but it keeps filling...

House is 72 years old, in Ontario Canada...

Thanks,
I would want the trench 10-12 inches deep, depending on frost depth the footing could be much lower.

The deeper you put the trench down the more water you will have to pump.

Was there a gravel layer under the slab?
Hello,

No, there was No gravel under the cement... About 3-4 inch's of cement, then dirt.. another 1-2 inch's down was Very wet dirt...
Hello,

No, there was No gravel under the cement... About 3-4 inch's of cement, then dirt.. another 1-2 inch's down was Very wet dirt...
Ayuh,..... Sounds like a very high water table,.....

Whatever pump you use is gonna run alot,....

I'm the one that recently found a square cement encased hole on the floor (Maybe 2 feet deep), that keeps itself full of water.. I've pumped it out a few times, but it keeps filling...
Why not use this hole for yer pump,..??
Ayuh,..... Sounds like a very high water table,.....

Whatever pump you use is gonna run alot,....



Why not use this hole for yer pump,..??
Hello,

My plan is to use this hole, but I'm wondering if it's too small though considering the amount of water I might be dealing with now...???

If the water table is really this high, am I wasting my time with this?
You gotta do something, so I don't think you're wasting your time. You've exhausted any possibility that surface grading may improve conditions?
You gotta do something, so I don't think you're wasting your time. You've exhausted any possibility that surface grading may improve conditions?
Hello,

Yes, the outside is all done, or almost completed (Need to finish one gutter) The old Cinder block walls are leaking at times, so I'm working on repairing all the walls as well, and was planning on putting up dimple board leading into my drain system in case in the future if the walls decide to leak again, which I'm sure they will...

I'm just concerned now, will the pump be running all the time attempting to drain an entire water table?

Thanks
I mean, what's your alternative to the pump?
Hello,

My plan is to use this hole, but I'm wondering if it's too small though considering the amount of water I might be dealing with now...???

If the water table is really this high, am I wasting my time with this?
You want it a little lower than normal to give the dirt a chance to dry out under the slab.

You can decide what to do before you finish. you set up the pump with the float to turn on maybe 4" below the slab and time how long it runs and time how long it takes to fill back up to that level and then try it deeper and see the difference.
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and was planning on putting up dimple board leading into my drain system in case in the future if the walls decide to leak again, which I'm sure they will...
Ayuh,..... The real Cure, would be doin' this, ^^^, Outside the foundation, with a drain to daylight,......

Otherwise, a pump or two is where ya gotta go,.....
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let me understand - you're thinking your home's foundation is maybe 3"-4" thick vertically ? that is seriously undersized impo so i'm thinking i don't 'get it'
10-4 on the dimpleboard,,, consider 2 pumps ( they're cheap - $150 for 1/3rd hp automatic 'gould' on ebay incl shipping ) w/1 mounted 5" higher than the other as backup pump !
sumps we use are 22gal - sometimes we'll double them up side-by-side,,, in fairness, some pumps never turn on as the managed leaking water percolates into the soil
let me understand - you're thinking your home's foundation is maybe 3"-4" thick vertically ? that is seriously undersized impo so i'm thinking i don't 'get it'
The Concrete Floor is about 3-4 inch's Thick... With no gravel under the cement...

I dug some more yesterday, and discovered that my footers are basically directly under my basement floor, so the basement floor slab is sitting on top of the footers... The footers are also a lot smaller then I expected, but I'm no engineer... They must be the footers as I was able to push a metal rod through the dirt underneath, well past where the wall would have been...

So the current "Hole" in the floor that I recently discovered, full of water, I'm planning to use as my Sump Pit location... What would you do, use the existing hole (Cement walls, 24" X 27" but only 20"Deep), or would you jackhammer that to bits and drop in a plastic sump pit?

Thanks
3-4" thick floor's fairly common,,, its called a 'floating slab' & serves 2 purposes: 1, prevents bsmnt walls from inward movement due to exterior soil pressure; & 2, is nicer to walk on than mud.dirt

IF that existing "Hole" in the floor is in the right location for your situation, then its fine IF the managed water can easily drain into it,,, we ALWAYS set plastic sump w/multiple 3/4" drilled holes into side & bottom to allow the water into the sump,,, both under & around the sump is 3 to 4" of clean drainage rock - we use #57,,, we also line the excavation w/soil filter cloth

ALWAYS install cleanouts too,,, these systems are low maintenance, NOT NO maintenance
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3-4" thick floor's fairly common,,, its called a 'floating slab' & serves 2 purposes: 1, prevents bsmnt walls from inward movement due to exterior soil pressure; & 2, is nicer to walk on than mud.dirt

IF that existing "Hole" in the floor is in the right location for your situation, then its fine IF the managed water can easily drain into it,,, we ALWAYS set plastic sump w/multiple 3/4" drilled holes into side & bottom to allow the water into the sump,,, both under & around the sump is 3 to 4" of clean drainage rock - we use #57,,, we also line the excavation w/soil filter cloth

ALWAYS install cleanouts too,,, these systems are low maintenance, NOT NO maintenance
Okay, So your recommending to use the location, but remove the cement walls, etc. in this hole and use a proper plastic sump pit... Okay, Makes sense..

And yes, I noticed one of your other posts about adding Clean-outs, which I'm planning to do now as well..

Thanks for your input, I'm sure I will have more questions soon.. :)
Do not remove the cement walls.

With the cement walls you can put the pump in with no round plastic basin and no need to wrestle with gravel, just a shallow flat layer of the latter on the bottom needed.

That "hole" with the cement walls, given the size you specified, will perform better as-is compared with a typical pit with basin builit from scratch because it has more space to store water between pump cycles.

Carefully drill two 4-1/4 inch holes in the cement sides of your defacto pit to accept the ends of the basement perimeter drain pipes coming in on the level or a slight downslope. If the pit is too far in from the foundation walls then extend the perimeter drain pipes inward to reach the pit. If you are unsure of the height for these 4-1/4 inch holes, their being a tad low is better than a tad high. (Actually it will work with one 4-1/4" hole but the pump cycling will be a little less efficient.)

When you dig the perimeter trench for the 4" perforated drain pipes, do not dig below the bottoms of the foundation footings.
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allan, you do this work for a living ? ? ? here's my take: door A, $35 sump properly installed in the right location vs door B, use an incorrectly constructed 'hole' he found in the floor,,, hhhmmmmmm ( thinking )
tell you what - i'll take door A be be certain its done right THIS time,,,
there's been no posting of the existing hole's capacity so on what comparison do you base your post ? good sumps = 22.5 gallons vs existing 'hole' = htf does anyone know ?

IF you're a pro, that's fine - let me know why you posted that advice - i'm not too old to learn,,, jomamma is but that's another story

1 more thing - this is just a guess but i'll bet the hole's walls are concrete, not cement
The hole's dimensions were given as (rectangular) 24" x 27" x 20" deep. I estimated that the volume of the hole below where the perimeter drain pipes dump in is about 25 gallons which gives extra time for some additional water queued up in the perimeter drain pipes to dump into the pit during the same cycle before the pump sucks it dry and stops.

The pump should start before the ends of the perimeter drain pipes as seen in the pit get more than 2/3 covered. Maybe a higher water level if you know that the drain pipes come in with a downward slope. How many gallons does your plastic basin hold before filling up past the drain pipe holes?

More opinions: http://www.cockam.com/watertab.htm
Hello All,

I'm just worried the current "Pit", "Hole", whatever, might be too small for the amount of water I think I'm going to need to deal with..

Example, I just dug a test whole, about 2 fee away from that Pit, and once I got about 10-12 inch's down, the hole started filling with water.. Everything under the cement floor is wet already... So I have a feeling there's a larger water problem then I anticipated.. It's just all underneath...

Thanks,
I'm just worried the current "Pit", "Hole", whatever, might be too small for the amount of water I think I'm going to need to deal with..
Ayuh,..... I see that as a function of the pump(s), not the size of the pit,.....
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