Replies

1. 
   john7g | Sep 01, 2009 01:55pm | #1

   while you have the excavator have you thought of perimiter drains around the outside of the foundation to help prevent the water form getting inside in the 1st place?  Do you know the source of the water? 

   If you're only going to dig a ditch away from the house, ditch witch type machines are better and quicker. Hand dig what the ditch witch can't get which shouldn't be much, even next to the house.

   CALL BEFORE YOU DIG.   to locate  all your underground utes.

   For pipe I prefer rigid PVC.  Any slope is good but aim for 1/4"/ft if you can. 

    

1. 
   craig19380 | Sep 01, 2009 06:20pm | #2

   John - thanks for the info. I have called 811  (1dig) and they are coming out to mark for the utilities.

   I'm pretty sure that I have springs that run directly under my house. Spring time is when it really kicks into gear. I live at the base of a hill. I think I need an excavator...probably need to go down around 8' .   My main concern is how far down, under the concrete floor pad , should I begin the pipe ?

    

   Thanks again

1. 
   john7g | Sep 01, 2009 08:30pm | #3

   for sump pump drain I'd run the drain pipe through the foundation and not under it.

   for a perimeter drain pipe on the outside of the foundation go right to the footing being careful not to undermine it. 

   but I'm missing the reason for "how far down, under the concrete floor pad , should I begin the pipe ?"

1. 
   craig19380 | Sep 01, 2009 11:27pm | #5

   John  -thanks again for the reply. Maybe I'm just not knowlegeable enough on the subject. My thoughts were to dig a sump pit in the left front corner of my basement. dig a trench on the outside of the house, deep enough down to tie into the new sump pit. and run the pipe down the trench (perpendicular to front of house) down hill to empty into daylight. The sump pit will extend down from the top of concrete pad in basement , approx 2 - 3 tf in depth.

   My question was " how far below the concrete pad should the pipe be started ?

   Maybe the issue is that I don't know exactly what the foundation is comprised of....

   The basement wall is made of cmu's. Under these I would imagine is the footer ? Under that crusher/gravel ?

   You are saying to bring the pipe through the foundation, I'm not sure where that means?

    

     

1. 
   john7g | Sep 02, 2009 12:08am | #8

   through the foundation = drill a hole through the CMUs. 

   Under those CMUs in undisturbed soil will be a footer that is wider than your wall to spread the load of the house onto the soil.  If you were to remove soil to run a srain line from your sump it's difficult to return the soil back to orig and there becoems apth for water to flow taking soil with it and undermining the footing without you knowing it.  It's my opinion to never screw with anything under the footing or the footing itself.  Take a look at the attached pic, its probably close to what you have. 

   Drilling a hole for the sump drain through the CMUs will not be that difficultas long as you locate the hole in one of the 2 cells in the CMU and not centered on the brace that's in the center of the CMU.  Resealing with mortar and your preferred sealant is pretty simple.  I'm assuming that in your sump pit will be a powered sump pump. No? 

   Better option is to try to prevent the water from entering the basement in the first place with perimeter drains.

2. 
   cussnu2 | Sep 02, 2009 06:53pm | #13

   to go through the CMU, he would have to use a pump which is what he is trying to avoid.

3. 
   DanH | Sep 02, 2009 01:24am | #12

   Basically, you only need to drain the water table down to below the floor of the basement. However, keep in mind that the water table will, when drained, slope down towards your drain pipe, and will be higher elsewhere. If you can successfully locate your pipe in the actual "underground stream" then this isn't a problem, but otherwise you need to go deeper to keep the entire floor dry.Typically, in a new basement, the drain tile is installed in two loops, one around the outside of the foundation footer and another around the inside. This guarantees (as much as any such thing is guaranteed) that the water table will be drained down to below the basement floor across its entire expanse. If your basement, with it's existing sump system, already has such tile installed, you can tap into that and be good to go. You can get a feel for how deep you need to be by noting where the existing tile empties into the sump -- aim for about 6" below that and you should be pretty well off.Otherwise, you should attempt to tile as much of the perimeter of the foundation as you can, going down a minimum of 6-12 inches below the basement floor. The more of the perimeter you can hit, the shallower you can go and still be effective.Also, in addition to calling your locator service to mark your utilities, you should obtain some sort of transit or optical level (or in a pinch use a water level) and determine accurately where on the downslope your pipe should exit (allowing for the roughly 1/8-1/4" per foot slope of the pipe). You don't want to get it all buried and discover that you didn't bury it deep enough or slope it enough.
   As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz

2. 
   KFC | Sep 01, 2009 11:37pm | #6

   for sump pump drain I'd run the drain pipe through the foundation and not under it.

   for a perimeter drain pipe on the outside of the foundation go right to the footing being careful not to undermine it. 

   but I'm missing the reason for "how far down, under the concrete floor pad , should I begin the pipe ?"

   I think he's trying to figure out how to do an interior french drain that is operating simply on gravity to relieve his sump pump from constant duty and to serve when power is out.  So he's kind of asking how low does it need to be to collect the "spring" water, while remaining high enough to drain with minimal digging.

   I agree he should address the outside as well, especially since he says he's at the base of a hill.  I'd run perf pipe (in gravel and fabric) around the three uppermost sides, double barreled with solid to catch downspouts, and tie them together on the down hill side into solid all the way to daylight, with cleanouts here and there.

   As far as an interior french drain, that's kind of a #### shoot.  You could go down 8 feet, but if it really is a spring six feet away, miss it anyway.  You could have an interior perimeter drain, but if the "spring" is in the middle, the water level has to saturate the entire sub base before it will collect in the perimeter. 

   If you have proper drainage base under your slab, then any sump should catch the water as it rises up, so in theory all you'd need would be to use gravity to drain the sump, with the pump acting as a backup.  A pipe near the bottom of the sump would be deep enough.

   Did I get any of that right?

   K

   edited to add: I didn't see the op's subsequent comment about footing concerns being his depth issue before I posted this.

    

   Edited 9/1/2009 5:10 pm by KFC

1. 
   Bing187 | Sep 01, 2009 11:58pm | #7

   I could be wrong, but I think John is on the wrong track.

   You have a sump pump in the cellar, right? Hopefully, there is an interior drain system (french drain) that runs the perimeter inside under the floor in stone, which empties into the sump pit. You should be able to tell by a hole in the side, or two sides of the pit w/ 4" pipe sticking thru.

   Your problem is ground water rising during wet season...if this  is ground water, it's coming from below, not thru the walls. You want to daylight a drain from under the slab to grade somewhere. Sound right so far?

   Ditch witch won't work here, you need a 7' deep trench, and room to put 4" sched 40 in, and pitch it. 1/4" to ft is good, though level will still drain.

   Only caution aside from the already mentioned digsafe stuff is that. 1) the builder may not have run a drain to daylight for a reason...like ledge in the path of where you want to run your pipe. 2) if there isn't stone under the slab, with perforated pipe to let the water flow easily to the point you're draining to....You may still not be able to keep up. Having said this, *usually* where there's a sump pit, there's a drain system (or at least stone) in place. I would check out the sump pit; if there's pipe, that's what I'd tie the daylight drain to.

   Hope this helps

   Bing

2. 
   KFC | Sep 02, 2009 12:13am | #10

   I get everything you're saying, but still would encourage the exterior drainage, unless I knew for sure there was only a true spring causing the issue.

   Relieving the subsurface plume of water uphill of the house almost always helps.

   kl

3. 
   john7g | Sep 02, 2009 12:12am | #9

   I'm starting to think your right. 

   you & bing replied while I was building my previous post.  I don't like the idea of messing with anything under the footer once the footer is poured. 

4. 
   KFC | Sep 02, 2009 12:15am | #11

   And I was starting to think I was wrong...  about his depth concern, anyway.  Multiple posts happening rapidly here.  Kind of nice, actually.

   k

    

5. 
   craig19380 | Sep 03, 2009 02:27am | #18

   Thanks to all that have responded. John - thanks for the foundation drawing, appreciate your time !

    KFC/all - yes I have an existing sump in the left rear corner of my basement. I'm not sure though that there is a french drain. I suppose I would know when I dig the other sump pit. The existing sump is made of  what I guess is clay chimney flue  pipe ? approx 11" x 11" x 1" in wall thickness. Doesn't appear to have pipes leading in from a french drain system. If needed , I could dig and install the french drain to ensure the spring water flows from the existing sump to the new sump.

   I still have a question though , once the trench is dug , would I need to tie into the new sump or simply the external tiles , on the outside of the house, id existing ?  I had intended to glue and drop/roll the pipe into place and hoped to pull the pipe in from the basement and connect from there.

   Same question I'm still not clear on, if I'm running the pipe to the new sump. Based on John's drawing, I would be running the pipe under the footer, correct ?

   Thanks again for all the great advice/thoughts

2. 
   DanH | Sep 01, 2009 08:50pm | #4

   Be sure to call your states locator service and have them mark utilities. And remember that they likely won't mark your house's water and sewer lines.

   As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz
3. 
   BryanSayer | Sep 02, 2009 08:00pm | #14

   There are battery backup sump pumps, using marine batteries. Basically a second pump is connected to a marine battery, and maybe a recharge station or something.

1. 
   cussnu2 | Sep 02, 2009 08:53pm | #15

   safer still are water driven backup pumps.

   Personally, while a drain to day light would be more foolproof, if you going to dig a second sump pit you would probably be money ahead to just put in a second pump and not bother with the digging.  The second pump should in theory reduce the work load of the first pump (and if it doesn't the daylight drain won't either) plus you have a builtin backup failure pump.  I would then add either a battery backup or a water backup pump.  Water driven won't work if you are on a well since the well pump won't come on if the electric is out.  Anyway, you would save the hassel of digging your whole front yard up not to mention there is a not so small risk of collapse in trenches like that and unless you have a steel reinforced shoring cage to work in, it can be a dangerous situation.

1. 
   brownbagg | Sep 02, 2009 10:58pm | #16

   7 feet DO NOT GET IN THE TRENCH FOR ANY REASON, glue the pipe together and then roll it in. 7 feet will kill you. to do legal you have the cutback 10 feet

1. 
   cussnu2 | Sep 02, 2009 11:12pm | #17

   Glad I'm not the only one that thinks safety.