# Drywell installation



## hamproof (Jan 4, 2010)

Hi,
A bit of a background info. I've an issue with standing water on the lawn. This happened a few years back. I bought the house from the original owner. For the first 4 years, there wasn't any issue. Then whenever the sump pump kicks in, the discharge line on the outside that goes to a pipe underground overflows. 

Suspecting a block in the line to the storm drain, I hired contractors (a plumbing and sewer company) to dig up the old lines and replace. But it turns out the discharge line was never connected to the storm drain and is confirmed by the city inspector. Also, it is almost impossible for me to tap into the storm drain according to the inspector as they do not allow an arbitrary tap. So, the sump pump just discharges to this black flexible tube that goes in and under a tree in my yard. The guys who came did not dig any further under the tree. So, as a temporary solution, a PVC pipe was installed and routes the water somewhat to the back part of the house.

However, after 2 years, this is again causing standing water. I suspect the original black tube actually goes under the tree and somewhere else where a drywell already exists. But perhaps to find this and maybe replace the original black tube might be more time consuming as there's a big tree above it now.

Now, I would like to install a drywell. I found some online (flo-well, naturalstore) for $150 or so including shipping. Who do I call to do the install generally? Plumbing guys? Or landscaping guys? How much can I expect to pay? I used servicemagic to find a local company and was quoted $2400 and up. I figured labor can't be more than $1000. 2 guys at $60/pp for the whole day ($120 x 8hr = $960). 

Thanks.


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## nap (Dec 4, 2007)

I can't give you much of an estimate of costs but you forgot equipment costs. Generally there is a $/hr charge for the equipment used to dig the hole. There may or may not be an operator charge on top of that.

You also have to consider the gravel that is needed to surround the dry well.


curious about the black flexible tube; were there any slots in it? was it covered with some sort of mesh stocking material?

If either of those were present, the tube was actually the means of drainage. If it was installed directly into the dirt, that might have been the cause of the blockage itself. It needs a bed of gravel to help things drain quickly.


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## Daniel Holzman (Mar 10, 2009)

Installing a drywell under your circumstances may not do any good. Presumably the sump pump comes on because you have a high water table. Putting in a drywell that is below the water table will do no good at all, since the drywell will simply fill up with water and provide no storage. You need to verify that the specific location you plan to put the dry well in has a groundwater level below the bottom of the drywell.

This can be done by excavating a small hole at the location of the drywell, and seeing how high the water is. Remember to do this when groundwater is high, typically the spring, as that is when you will need to pump.


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## hamproof (Jan 4, 2010)

I only saw maybe 2-3 ft of the black tube only. Nothing unusual. No mesh, no holes. Previously the sump pump discharges into a PVC pipe which connects to this black tube just on the outside of the house. This black tube then goes into the ground. I only realized it goes under the tree after the guys came out to dig it out. We initially thought this black tube goes to some PVC pipe which taps into the storm drain.

This company snaked it initially and didn't get more than 4-5 ft. Not sure why we all assumed it is connected to the storm drain  Wasted a a few hundred bucks paying them for a job they didn't really do since they were out with a little tractor (not sure what it is called) and 2 guys who were onsite for 4 hours while waiting for the city inspector.

Anyway, I assume the company I hire to do the install will know to do the water table test to make sure it is feasible. I suspect there's already an existing dry well somewhere in front of the property. The black tube can't just go underground to no where. But since they can't snake it past 4-5ft, not sure if it is worth trying to find it.

The house was built in 85. I bought it in 01. This happened around 05 time frame. The neighbor next door who has been there since the houses were built said there wasn't any issue previously. So, I assume the black tube and whatever it is connected to is doing its job for a good many years.

But I'm having a hard time finding contractors. For drywell install, do I contact plumbing/sewer or landscaping guys? 

Thanks.


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## nap (Dec 4, 2007)

I would think a plumbing contractor although since this is not dealing with septic waste, I wouldn't think it would have to be a plumber.


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## hamproof (Jan 4, 2010)

If a drywell is feasible but cost prohibitive, what other alternatives do I have? Thanks.


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## hamproof (Jan 4, 2010)

I talked to the city guy again and he said a drywell will not work due to the soil being mostly clay  He sympathizes with my situation since his own house has the same problem too. Also, I asked him about a french drain and he said it is not going to work either and also the city will not allow water to drain to the sidewalk. 

He said previously, the sump pump discharge was probably discharging to the side walk though I'm not sure how this is possible since there's isn't much slope from the house to the side walk. I can't see how the previous black tube that goes from the side of the house to under the tree could possible go all the way to the front of the house near the sidewalk. Is there a way I can see where this outlet could possibly be? 

The only thing I see unusual in my yard is this circular metal plate. Around 6" in diameter, with the engraving "Water Works" if I'm not mistaken. Maybe I should dig around it to see what the heck it is?


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## nap (Dec 4, 2007)

that is likely the access to a water valve to be able to shut off the water to your house.




unless there is a more accepting type of soil below the clay at an accessible level, I don't have any ideas for you. You might speak with people that build in that area or maybe even the city folks and ask if the clay is all there is or is there something below it. If you have a different type of soil below accessible, you could dig your drywell deep enough to allow drainage into that soil.


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