Designing a dry well for yard drainage

[Badfish740]

What granpajohn said. 3 layers of progressively smaller sizes of stone. With regard to just filling and grading with dirt, one of the obstacles I'm dealing with is a small lot with a lot of obstructions. If it was as easy as backing up a triaxle dump and dropping a full load of dirt that would be one thing. I'm dealing with a spot in the back corner of the yard surrounded by fences on all sides. The only access to the backyard is through a 10' wide gate. I feel it would be easier to bring in loads of stone in my pickup a little at a time. I can drive to the quarry just up the road on a Saturday, pick up a load, back it into the yard, and shovel it off. Clean dirt, at least around here, is harder to come by, and IMHO, harder to move.

 

[M1sterM]

Sounds like a good plan. And I agree about using the landscape fabric...it's necessary if you want to maintain "interstitial space" for water collection. Not sure if you really need 3 sizes of stone, though. If you don't get any "minus" material (e.g. no fines in the stone), you could probably get away with just the 2 inch stone for the drainage layer (or 2-4 inch, depending on how your yard classes their stone).

Are you going to leave it as a gravel pad (for piling firewood, perhaps?), or going to cover with topsoil and plant it?

 

[razerface]

I believe those numbers are the stone sizes; not the layer thickness

.

oh,,,I was reading it in english

" = inches
# = number

example: 4" = 4 inches,,,,,,,,,,,,,,,,,,,,, #4 = stone size (and it will not be 4 inch stone)

 

[Ashful]

Call me simple, but I'd order a tri-axle of topsoil and grade out that low spot. Water runs downhill, and it sounds like your neighbors are downhill.

You have to be a little careful here, in that you are typically not permitted to affect runoff to or from a neighboring property, but in this case it appears net runoff will remain un-changed. You are simply varying your storage capacity prior to runoff.

Stone, fabric, etc... is that what the rest of your yard is? Keep it simple. I've done this in many places on my yard, and once grass is established, it's a stable solution.

Do note that what most sell as "top soil" is very heavy in clay. You typically want to order "premium topsoil", or have some organic product mixed in with the top soil (ask supplier for recommendation), if you want anything to grow in it.

 

[Badfish740]

Call me simple, but I'd order a tri-axle of topsoil and grade out that low spot. Water runs downhill, and it sounds like your neighbors are downhill.

Can't fit a tri-axle into the yard-no way, no how. The rationale is that stone is cheaper than topsoil and easier to move in my case.

Do note that what most sell as "top soil" is very heavy in clay. You typically want to order "premium topsoil", or have some organic product mixed in with the top soil (ask supplier for recommendation), if you want anything to grow in it.

That's the thing-I don't want to grow anything (got enough to mow, fertilize, etc... ) This is going to be combination firewood processing area and firepit/hangout area. If I tried to grow grass there it would just get torn up and turn to mud anyway.

 

[razerface]

That's the thing-I don't want to grow anything (got enough to mow, fertilize, etc... ) This is going to be combination firewood processing area and firepit/hangout area. If I tried to grow grass there it would just get torn up and turn to mud anyway.

i think we are all confused since your first post mentioned you would be covering everything with sod. I was anyway!

After grading,,,,,there will be no more mud, even if you use dirt,,,,that is the point of grading,,, the water will run off instead of laying in a pool,,,since the low spot will no longer exist to collect water.

you will have to use a top layer of stones with fines to make surface water run. Big stone will not do that. Bigger stone on the bottom will help the sinking till it all settles,,, if you have room. If you get grade wrong,,and go high,,you will move the wet spot to a different place where you will not want it. Run a laser and see what you have.

 

[Badfish740]

i think we are all confused since your first post mentioned you would be covering everything with sod. I was anyway!

Whoops-the project sort of evolved in my head which never made it into a post. I thought about it some more and questioned the decision to put grass there given what I want to use the area for.

 

[Highbeam]

You have a 10 foot gate? That is all you need to back in a tri-axle. Max width of that truck is 102" and he will have no problem making it through a 10 foot gate. Assuming there is a path on either side of the gate to drive to your hole.

Skip the fabric, you aren't building a road. You are filling a low spot in your yard. Fabric is for separation, it is to keep the gunk from pumping up and contaminating your gravel with clay. That pumping up will only occur if you are driving on it which kneads it like dough if the ground is soft. After you fill this hole it will "heal" and become just as hard as the surrounding ground over the summer.

A little at a time with your pickup will certainly work and can be a pleasant chore if you have the time. If you want gravel, choose a crushed product that includes the fines. In my part of the country we call that "5/8 minus" or "1.25 minus" meaning the big rocks were crushed and everything able to pass through a 5/8" or 1.25" screen is in the pile. We use the 5/8 minus stuff right under asphalt paving.

If you're looking for a complicated project, get into plumbing or sheetrock in the home. What you have here is a hole in the groudn that needs filling.

 

[Badfish740]

You have a 10 foot gate? That is all you need to back in a tri-axle. Max width of that truck is 102" and he will have no problem making it through a 10 foot gate. Assuming there is a path on either side of the gate to drive to your hole..

I thought the gate would be the limiting factor, but regardless, after you get through the gate and the 10' wide space between the fence and the side of the house there are two trees in the way and no room for the truck to make a swing to back around them. They are mature sugar maples and as much as they'd make good firewood I ain't cutting them As for the rest of it, 10-4. I think I have a plan now...

 

[Ncountry]

I would not be overly confident in filling the low spot with topsoil. The underlying problem (the clay and the slope of) is still there. If you have a bowl full of water and fill it with top soil, you have a bowl full of mud. Covering the area with land fabric 1st and then some stone,fabric ,and top soil again would probably float the yard over it. As long as the new topsoil level is above the old water line

 

[Butcher]

Yessir I'm cornfused.

 

[bsa0021]

I don't mean to dispute the professionals here, but the previous house I owned had a major water issues. All the surrounding properties were sloped toward my property. The water was so bad when it rained my garage would flood (rear garage door) from the water running from the back of the property into the rear door.
Fed up, I started digging / picking by hand. It was all clay. I went down as far as I could and filled the hole with broken concrete pieces from an old slab. Covered with landscape fabric and topsoil. Of course I was in my 20s so digging by hand was a challenge. I don't know why it worked but it did.

 

[Badfish740]

I don't mean to dispute the professionals here, but the previous house I owned had a major water issues. All the surrounding properties were sloped toward my property. The water was so bad when it rained my garage would flood (rear garage door) from the water running from the back of the property into the rear door. Fed up, I started digging / picking by hand. It was all clay. I went down as far as I could and filled the hole with broken concrete pieces from an old slab. Covered with landscape fabric and topsoil. Of course I was in my 20s so digging by hand was a challenge. I don't know why it worked but it did.

For the heck of it, I decided to do a little investigating of my soil. I pulled a soil report and the soil for my area is described as "gravelly loam." From Googling, loam sounds like a good thing, but it still doesn't seem to drain well, but I suppose the grade issues have to do with that as well. Anyway, I got back to the post hole I had been digging, and went down as far as the handle on the digger would let me (about 40"). The hole kept filling with water as I was digging so I ended up getting my shop vac out and sucking the loose stuff out as I went. The soil seemed uniform all the way down. Basically its an orangish-brown soil that seems sticky but gritty-there's a lot of broken up rock in it as well. I took some of it and spread it out over a rag and ran some water over it. With the silt washed away I was left with what looked like sand, bits of rock, a lot of gold flecks (mica, I think), and little globs of soil with the consistency of gritty silly putty. I'm guessing that's clay. About an hour after I finished digging the hole was completely full of water and still is, granted it's been raining on and off all day. The water was running in from the bottom fast enough that I could see it. Is the ground really just this saturated or could I be dealing with an underground spring?

 

[semipro]

.could I be dealing with an underground spring?

That's why I asked above if you were on a septic system.

 

[Badfish740]

That's why I asked above if you were on a septic system.

No, no septics around here. The subdivision was built in 1967 right after the town had a municipal water system put in. I have an old aerial photo dated 1938 that shows exactly where my house is now-it was just farmland then. Any other kind of waterline, delivery or waste, is unlikely as well. My water and sewer come from the street in front of the house, as does the water and sewer for the house behind me. There are no easements on my deed.

 

[blades]

Quite possible you have a spring/ under ground seepage bubbling up there, Likely caused by all the other construction/ basements over the years. A secondly would be if at anytime in the past was there a septic system or just a holding tank, prior to city sewer? If you do not know it would be wise to find out what was there before the subdivision was built.
So many subdivisions have been built on marginal land that at one time were runoff buffer areas. Back filled to create lots, a practice that is highly regulated now but wasn't many years ago.

 

[Badfish740]

Quite possible you have a spring/ under ground seepage bubbling up there, Likely caused by all the other construction/ basements over the years. A secondly would be if at anytime in the past was there a septic system or just a holding tank, prior to city sewer? If you do not know it would be wise to find out what was there before the subdivision was built.

See my post above-just farmland.

So many subdivisions have been built on marginal land that at one time were runoff buffer areas. Back filled to create lots, a practice that is highly regulated now but wasn't many years ago.

I'm leaning toward this as the reason. I'm guessing the machines were brought in and the land was reshaped anywhichway without regard to all the stuff you have to get permits and variances for now.

 

[granpajohn]

A spring is ground water that reaches the surface.

Jurisdictions that certify perc tests for septic systems, only allow a wet season test because of seasonal high groundwater. That season is now for a reason.
(Here is the schedule for my county:
(broken link removed to http://www.aahealth.org/programs/env-hlth/well-septic-systems/wet-season-perc) )

I think you probably have just uncovered high groundwater. Typical for this time of year.

 

[woodsmaster]

I would say there is spring, septic tank, sewer, something under that area. The grass is green there and that means its warmer there. Something in the ground warming that area. Often after a tank is buried the ground will sink like that over it from all the dirt not making it back directly over the hole.

 

[Badfish740]

I would say there is spring, septic tank, sewer, something under that area. The grass is green there and that means its warmer there. Something in the ground warming that area. Often after a tank is buried the ground will sink like that over it from all the dirt not making it back directly over the hole.

I talked to my county NRCS rep and found that its just high groundwater as grandpajohn said-not much I can do about it except fill the area with stone. Its going to be in the back corner behind the barn, so I'm not as worried about it as I was. The town (we have municipal water and sewer) confirmed that there are no lines, tanks, culverts, etc...of any kind running under my property and the neighborhood was built new with public utilities in the late '60s. Before that it was farmland, and examining old aerial surveys confirms that there was nothing here but cropland (no old buildings, etc...).

 

[Lake Girl]

Justwood has a valid point on a cistern. A small one, a couple/few interconnected barrels as you initially described (geotextile surround to stop silt infiltration) and a small pump, would provide water for gardens and washing vehicles. Something to think about especially if you are on metered water.

Bring in rock as described above so the area is usable...