Sump pumps, storm drain, french drains and flooding

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I've been consulting with a neighbor about upgrading his sump pump system after a nasty failure. We've already replaced the existing pump that sits in a sump at the foot of the basement steps, outside of the house with a Home Depot cheapy with a 2 year warranty that's about to expire.
One problem is that the cord was (and still is) running under the door, to a non-GFCI outlet in the basement. Since the area enclosing the foot of the stairs is all cinderblock and brick, I suggested the he run some conduit and mount a weatherproof outlet high on the stairwell wall to power the pump. What's the preferred method for making the electrical connections to sump pump that has a 3 prong 110 VAC and sits outside the house in a concrete and cinderblock stairwell?
Second question: When his house floods, he says that water comes up quickly through a drain in the floor under the basement sinks. He believes that this is a storm drain and not a sanitary one because the occasional leaf or piece of street debris will come up but never raw sewerage. He says the water smells like streets do after the get slightly wet from the rain. That, to me, says storm drain.
He also says that when this happens, the sump pump is NOT pumping continuously. The floor of his basement is all dug out around the perimeter - I assume that French drain was to deal with weeping cinderblock walls, which we all have to some extent in this neighborhood - the site of an old natural spring. Neither of us knows anything about the French drains other than mine was dug in 1971 because they wrote that in the concrete!
I think we're seeing two problems here. One is that the sump *does* overload in a heavy rain as it's happening. That's not a plumbing problem as much as it is a landscaping one. Regrading and perhaps gravel runoff trenches with perforated drain pipe should reduce the flooding of the stairwell (very impressive - can rise several inches in just a few minutes).
But I don't think any of the sump pump work we do is going to affect the water that pours impressively out of the floor drain about a day after very heavy rains begin and continue. When the weatherman issues flood warnings, that's when the floor drains tend to rise. We both got flooded when a hurricane passed by in 2003 or so, and both times we had water come up through the floor drain. Their houses sits noticeably lower and closer to the old spring and is graded so that a lot of water passes by the house on both sides.
So do the immediate rains overflowing the stairwell sump and soaking rains causing water to come up from the floor drain mean they are not interconnected in any way? He is certain that the french drains connect both to the outside sump and the floor drain. However I see no marks on the concrete to indicate a connection. All I see in a very odd 1/2" square hole between the floor drain and the wall. It doesn't sound like connecting the sump to the storm drain system would be allowable by code. Why would you use a pump if you could just dump any excess down the storm drain?
I thought of using the cave diver's trick of dyeing the sump water and then flooding the floor drain with a hose to see if they were connected.
One solution he proposed is to dig a sump around the floor drain allowing the mounting of a traditional sump pump. I've seen how fast the water can come up from a 3" drain and when it does come up, it replenishes itself unless it is constantly pumped by a fairly powerful pump with a 1 1/2" outlet hose lifting it less than 8' - I guess a new sump to catch the initial overflow from the floor drain isn't a bad idea.
I suggested just using a 12VDC self priming pump and an electronic water detector and relay. Stick the inlet hose down the floor drain and activate it when the water is an inch below floor level. He says the occasional leaf debris will jam up the pump and it will likely need constantly oiling to keep from sucking air and burning up.
So, suggestions, brickbats, netnanny noises? (-;
-- Bobby G.
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On 4/3/2011 9:56 PM Robert Green spake thus:

I would think that your described method would be the way to do it. If the location is wet but not submerged, use PVC conduit; otherwise, use the raintight stuff (forget what it's called). And the outlet box should have a raintight cover over it that completely covers the plug (make sure it's big enough and correctly oriented).
--
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to a

the
and
pump.
sump
and
That's something I will probably have to ask my AHJ. I would think this is an indoor pump and that pumps mounting out-doors will be wired straight through with wire and no plug at all. Less of a chance some dickwad will unplug it when I am not home although IIRC, code requires external electrical devices to have a shut off switch, in which case a plug is probably easier to deal with.
This may all be rendered moot when we find out where our floor drains exit and when my neighbor regrades his house so that all the run-off from the street (he's at the bottom of a 5 block uphill run) rushed BY the stairwell instead of into it. Might mean even building a low wall around the area.
Thanks for the input.
-- Bobby G.
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*A weatherproof box with a bubble cover and a GFI protected receptacle.

*A backflow preventor could possibly prevent this from happening. Where does the floor drain go? Finding that out may expose another problem such as a clogged up dry well.

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system
sits
to
the
pump.
sump
It would have to be watertight and installing it will be a bitch. I can't see any way to do it without breaking up the floor. That may have to happen, anyway, and if it comes to that, I would probably dig a sump around the pipe, cut it lower and drop a sump pump in. That way, when water came up from the (assumed) city storm sewer, it would first fill the sump and then be pumped out. The floor drain would still be operational in this scenario.
Thanks for the idea. It's one of many things to consider.
-- Bobby G.
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*I saw somewhere on the World Wide Web a backflow preventor that was part of a drain cover. It had a built-in float that would rise up and seal the drain if water came backing up.
Check this out: http://www.plumbingsupply.com/floodguard.html
Here's a backflow preventor for sewerage, but you need to break up the floor to install it: http://backwater-valves.com/
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Different tack. Look into what might cause the backup. Story:
We had almost yearly water in the basement becaue of tree roots. Therefore we had the sewerline to the street (dating from ~1930) replaced. Since the neighbor across the street had done the same a few years back, and had recurrences of basement flooding after that, I asked the contractor who did the work to look into the town's sewerline in the street for blockages causing backup. He did, found debris and/or other problems and the town told him to fix that. Good for the contractor and us. So far that has fixed the problems. And the tree is doing fine although it is an ugly DPW oak. But it gives shade ...
--
Best regards
Han
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t-email.me:

the first obvious question:) does the homes basement or at least the level of the french drain sit above the elevation of the area?
a often ignored but very effective solution is to dig a trench from home to say street level install PVC drain pipe.
in a heavy rain situation the sump can let gravity drain off the excess water...
and you definetely need to find out where that floor drain?? goes. have a plumber run a camera down it.
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That's a good idea. We had a big 70 year old red maple die last year, and it was growing directly over the service connection. I would expect a plugged connection to the street to cause problems with water draining from the floor drain backing up. How does a blocked connector explain water coming from the sewer and back into the house?
<the first obvious question:) does the homes basement or at least the level of the french drain sit above the elevation of the area?>
Hell no! Home basement is 7 feet below grade and is about level with the big park out in back that always ends up with about an inch or two of standing water after a "flood alert" rain.
<a often ignored but very effective solution is to dig a trench from home to say street level install PVC drain pipe. in a heavy rain situation the sump can let gravity drain off the excess water...>
In this case gravity is my mortal enemy because it's the force enticing all that water to seek the lowest level it can. That's a little bit of my basement and a whole lot of my neighbor's who is graded even lower than I am. He's at the end of a T intersection where the five blocks that are uphill from us feed into. That started this whole endeavor because their basement stairwell floods just like a scene from "Titanic." We both thought increasing the pumping capacity at the sump would fix the problem with the floor drain. Now we believe that both the sump and the floor drain are not interconnected.
<and you definetely need to find out where that floor drain?? goes. have a plumber run a camera down it.>
It's looking like that's the only alternative, unless someone like an inspector or a water company worker can tell me otherwise. Believably. (-:
Thanks for responding!
-- Bobby G.
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It appears that the floor drain and the footer drain are separate. The sump probably pumps water that is coming in around the footer of the house, which is proper. However, the floor drain is going out to a stream, ditch or something that rises after the heavy rains. The floor drain is not needed. If possible, find out where the floor drain dumps into. Plug it. Be sure you plug it good. Make sure no water can seep by.
I have seen a few homes that a floor drain was put in and ran to a ditch/stream to avoid a sump pump, only to find out the basement floor is lower than the stream/ditch after a heavy rain.
Hank
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I think Hank is on the right track. As he suggested, I'd try temporarily plugging the floor drain and see what happens the next heavy rain. But first I'd try to figure out where it goes via the dye idea and the geometry of the location. The downside to plugging it would be that if it is indeed some kind of opening in the floor that lets water in when there is a lot of it in the ground in that area, then plugging it might leave that water with nowhere to go. That could result in enough pressure buildup that it could break the concrete floor, but more likely the water will just come pouring in somewhere else.
For the stairwell outlet, I'd use PVC conduit or Liquidtight with an outdoor outlet box with cover. GFCI either at the outlet or back at the panel for the whole circuit. While at it, if it's a breaker panel, I'd put in GFCI for all the basement outlets, since frequent water problems and having people there dealing with them is the norm.
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wrote:

system
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to a

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pump.
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and
quickly
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cinderblock
of
drains
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warnings,
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then
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<I think Hank is on the right track. As he suggested, I'd try temporarily plugging the floor drain and see what happens the next heavy rain. But first I'd try to figure out where it goes via the dye idea and the geometry of the location. The downside to plugging it would be that if it is indeed some kind of opening in the floor that lets water in when there is a lot of it in the ground in that area, then plugging it might leave that water with nowhere to go. That could result in enough pressure buildup that it could break the concrete floor, but more likely the water will just come pouring in somewhere else.>
Got a friend who was a Colonel in the Army Corps of Engineers who said that if the floor drain empties into a gravel dry well under the house, sealing the drain could turn my basement into a virtual "boat" and could crack the slab. We are both reluctant to close up the drain for a number of reasons. While I might consider "hatching it" with so sort of waterproof temporary covering, I don't think I would plug it completely. I'd prefer to stick a pump inlet into a rubber stopper so that I could pump out any water that exited through the drain. I was also tied up all day with doctors and didn't get a chance to call public works and talk about the problem with them.
<For the stairwell outlet, I'd use PVC conduit or Liquidtight with an outdoor outlet box with cover. GFCI either at the outlet or back at the panel for the whole circuit. While at it, if it's a breaker panel, I'd put in GFCI for all the basement outlets, since frequent water problems and having people there dealing with them is the norm.>
Almost all the outlets where there's any chance of water contact have been GFCI'ed, mostly in memory to my 4' 10" mom who, when I was a kid, picked up an old Philco radio during a basement flood. Her arm flexed so hard she hit one of the workers (house was still sort of under construction) in the stomach - I remember hearing him groan and double over (he was 6'6" and heavy and the radio went flying out of her hand. My first vivid memory of what electricity can do. My neighbor wants to leave his sump pump cord where it is - going under the basement door - but I am going to try my best to get him to do it the right way.
Of course, these discussions and other investigations are pretty much concluding that the french drains and sump are completely isolated from the storm sewer system. We began this endeavor assuming that heavying up the sump pumping capacity would end water coming up through the storm sewer drain.
We're now pretty much convinced that the improved sump pump won't help the floor drain problems at all. Tomorrow or Wednesday we will be flushing some detergent down the drain in the middle of the basement floor. If the effluent of the sump pump comes out sudsy, we'll know they are interconnected. I suspect we'll see nothing. Short of a pipecam, I don't know how to determine that the drain is connected to the storm sewer. I'm hoping some long-term inspector for the area knows the answer to that and what the best mitigation techniques are. If two adjoining neighbors have the same problem, I'm betting we're not the only ones.
Thanks for your input, Trader!
-- Bobby G.
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wrote:

a
and
and
quickly
or
cinderblock
drains
minutes).
very
the
hole
then
leaf
<It appears that the floor drain and the footer drain are separate. The sump probably pumps water that is coming in around the footer of the house, which is proper.>
I concur because I believe that the previous owner had considerable moisture that wicked thru the cinder block walls during heavy and prolonged rains. I think it was a basement moisture mitigation system wholly unrelated to the floor drain.
<However, the floor drain is going out to a stream, ditch or something that rises after the heavy rains. The floor drain is not needed.>
Actually, mine has seen service on a number of occasions I dumping the water heater, slop sink overflow, broken washer hose. I would be reluctant to "brick it."
<If possible, find out where the floor drain dumps into. Plug it. Be sure you plug it good. Make sure no water can seep by.>
Well, I have thought about that. A civil engineer I know said that if I do that, I could crack the slab because that water will now be trapped and possible under pressure but I think he said that not knowing that the floor drain most likely connects to the city storm drains. Hydrostatic pressure is what I believe he was concerned about.
<I have seen a few homes that a floor drain was put in and ran to a ditch/stream to avoid a sump pump, only to find out the basement floor is lower than the stream/ditch after a heavy rain.>
I believe, based on the time lag between the rain and flooding that the storm drains, which I believe this floor drains empties into, that the city storm sewer pipes (70 years old) just overflow and the water above a certain level back up into the floor drains. I base that assumption on the fact that we've both used those bell-shaped bottom-screened emergency pump sitting over the drain grate and the only stuff stuck on the filters are leaves. No human muck and as I said, a lot of "asphalt street after the first rain in a while" smell. Not enough to require even one scrape of the pump screen for a two day session. Lots of bug eggs, I found, so when the rains stop and the water level slowly returns, I flush it again. The rate and flow and "feel" of the flooding really suggests a free flowing system where water is seeking its own level.
Thanks for your input, Hank.
-- Bobby G.
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I guess I should have been a little more specific. Sorry.
When you find out where the floor drain runs to, it must be disconnected at that point and removed if possible. Then totally sealed off. Just blocking off at the floor could possibly get under the concrete floor and raise/crack it. ( as the civil engineer stated). So, you see the importance of disconnecting it and sealing it.
One poster suggests a anti-backflow valve (check valve) which may work, but they are not 100% successful. By disconnecting and sealing, the problem should be fixed permanately.
There are companies that will push a camera down the floor drain so that you can see where it possibly goes.
With the sump pump, the floor drain is basically useless and only a problem. You can run a hose from the hot water heater to the sump if you want to drain your tank.
Good luck.
Hank
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On 4/4/2011 12:56 AM, Robert Green wrote:

The problem sounds complex and the damages sound at least potentially very expensive. I would invest in a consultation with a licensed hydrologist who can inspect the plot, foundation, sump, french drain, etc. and make a competent recommendation. I'm told that such a consultation may cost about $400; but given the cost of mitigating the problem, the cost of doing well-intentioned but ineffective "repairs", and the potential costs of damages, it might be a good investment.
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wrote:

a
and
and
quickly
or
cinderblock
drains
minutes).
very
the
hole
then
leaf
<You need to determine where the storm drain goes.(Perhaps by putting dye down the drain) If it is linked to a soakaway/French drain, it serves no purpose and should be eliminated ofa better soakaway devised.>
Easier said than done. I have no idea where the storm sewer ends. It could be in a culvert at the end of the street or it could run underground for miles.
<If it is linked to a system of drains (sounds like it is) there are check valves available to stop most of the water coming back up the drain.>
There's a little voice in my head telling me "check valves on storm sewers aren't legal here." I don't know why I would think that, but I do. It's a question for my local plumbing inspector.
<You might consider two sump pumps, set to start at slightly different levels. They need to be regularly checked by operating the float switches.>
My sump has got two pumps. A 110VAC unit as the main, and a 12VDC unit sitting up on a six inch cinderblock to handle any overflow or failure of the AC pump for any reason. They do NOT share an output pipe.
<This is one of many types, you will have to find one suitable for your location/problem. http://www.rimbach.com/scripts/Article/PEN/Number.idc?Number >
The big issue now is where does the water go when it exits via the floor drain and where does the water come from when it flood the basement by coming up through the floor drain? The floor drain could exit into a gravel pit under the house or connect to a city storm sewer system. The next few days will be devoted to trying to figure that out - cheaply!
-- Bobby G.
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use
The one year that I tried that I was exceptionally unsuccessful. Solid rubber mat covered with three heavy cinder blocks *slowed* the rate of infiltration but water kept on flowing. A shaped rubber plug banged in with a mallet might work but the area's directly under the slop sink making access difficult.
Not even sure WHERE I would get a cork/stopper for a 3" diameter drain pipe.
-- Bobby G.
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I got an expanding rubber stopper (metal plates on either side of the plug with a screw and wingnut) for that at the local hardware store (now unfortunately defunct). But it didn't help if it forces the backup up the stack, where cracks let it out in a different area.
I think a backup valve instaled in the sewerline is the only choice. I also think that could be tricky if it ever got plugged up on the home side.
--
Best regards
Han
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On Tue, 5 Apr 2011 02:55:37 -0400, "Robert Green"

Go to a plumbing supply house and get a plumbing test plug of the appropriate size and use it. Have been using one in my basement for years, after one disaster, and it stops all the water, all the time
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On Apr 5, 9:15am, "Stormin Mormon"

I think it has been determine NOT to plug the hole at the basement. If you do, water may get under the basemant concrete, raise it and possibly crack the floor. Besides, it would still seep in around the foundation.
Those rubber plugs are mainly to keep out sewer gases, Radon and etc.
Hank
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