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White Gardens
11-26-2008, 09:15 PM
I know Pea Gravel is the standard for filling a trench after laying a drain pipe, but is that the best rock to use.

I was thinking any sort of crushed/screened gravel. I've always been told that angular rocks don't pack together so tight and allow water to flow through them better.

Any thoughts or experiences???

Smallaxe
11-26-2008, 10:06 PM
I did a french drain of the roof of a large house. I used baseball sized rocks at the bottom of a 2 ft. deep trench along the foundation. Filled it over with 1" - 1 1/2" wash stone up to, a couple inches of the top. Layed down fabric then put 2" of wash stone on top of that.

The best results that I ever had.
[My experience in sandy soil, so take it for what it is worth. :) ]

BTW, in the 'v' shaped hole - Put down fabric on the foundation side of the 'v'.

NC Greenscaper
11-27-2008, 09:20 AM
I usually use 1- 1 1/2 gravel, but I line the trench with fabric, fill with gravel (and corrogated pipe) in some cases), cover the top with fabric, cover that with sand/dirt, sod/seed.

White Gardens
11-27-2008, 10:39 AM
Well, Here's what I'm thinking.

26-28 inches deep, 2-3 inches gravel in the bottom, 4 inch corrugated tile pipe with silt sock, and fill the trench the rest of the way with gravel.

Do you guys still think I need to line the trench with fabric or is the silt sock take care of that for me.

The pipe is going to carry away water from two downspouts also. And I was also thinking about using PVC pipe with holes in it next to the house where my run is straighter, and flexible pipe where I start curving it out away from the house only so that it can be rooted out someday if there is a clog.

White Gardens
11-27-2008, 10:45 PM
So, after driving alone for 4 hours today, I come to a conclusion that I'm going to:

1.) Use a solid pipe 10 feet along the house so water from a downspout won't push water towards the foundation. Then turn it along the garage and turn it into either corrigated black pipe (with slits), or PVC with holes to at least the corner of the garage.

2.) I think I am going to line the trench with fabric to help keep silt out of the drain, and also have a sock on the tile pipe for added protection.

3.) then I think I'm going to fill it with washed gravel and fold the fabric back over to encase the drain.

I'll post some picks later after the wife brings the camera home.

vaham
11-28-2008, 01:50 AM
Well, Here's what I'm thinking.
Do you guys still think I need to line the trench with fabric or is the silt sock take care of that for me.

The silt sock only protects the pipe. If you enclose the stone in filter fabric, it's absorptive rate and transport capacity will remain fairly high over years of use. Without the fabric, especially in clay soils, over time the fine silt will infill all the voids between the stone, and when a dry spell hits, will solidify, and effectively seal off the migration route for the runoff-meaning the water does not get through the gravel to the pipe.

EagleLandscape
11-28-2008, 08:21 PM
yes, line the trench with fabric. we use like 3/4" rock. remember, the smaller the rock, the more water the drainage field can hold. just make sure its washed rock, and not something like decomposed granite, or crushed limestone. fines, are bad.

White Gardens
11-28-2008, 08:28 PM
yes, line the trench with fabric. we use like 3/4" rock. remember, the smaller the rock, the more water the drainage field can hold. just make sure its washed rock, and not something like decomposed granite, or crushed limestone. fines, are bad.

I've been wondering about the rock. I definitivly want at least a well screened. I was also thinking no more than an inch, but closer to 3/4 will work better.

So do I use an an angular/crushed stone, or more of a smother pea gravel style. I've been told both ways, I like the angular as it leaves more voids between the rocks, but I'm not 100% positive.

White Gardens
11-29-2008, 05:17 PM
Here's a few pics of the progress.

I first had to dig out 4.5 tons of river rock. there was probably 4-5 inches of it in that small area.

Found the old 90 year old clay drain tile. It is 2/3 the way full of silt.

Tree roots are no fun to to trench through but the machine did well. I only had to cut a couple of them.

The one pic of the machine next to the garage; almost slid it into the siding, but I will say, this Vermeer really handles tight spots well and had no problems driving away from a distance of a quarter of an inch next to the siding.

More pics will come as the trench comes along.

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White Gardens
11-29-2008, 05:20 PM
One more pic.

Also, the trench is no less than 26 inches deep, no more than 38 inches deep and 6 inches wide.

A 4 inch drain tile will be placed.

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EagleLandscape
11-29-2008, 05:24 PM
thats deep. are you just using it to carry the rain water from the gutters, or french drain and rain water from gutters?

White Gardens
11-29-2008, 05:31 PM
Part of the project is going to entail a buried electrical service, so the run next to the garage had to be no higher than 19 inches below the surface for the conduit to lay on top of my tile, and still be around 18 inches below the surface.

So that is why it is deep to start with, and I wanted a steep grade at the end to help push the water out faster.

It is going to work as a foundation drain, french drain, and drain for the gutters too.

EagleLandscape
11-30-2008, 12:47 PM
Looks good, have fun backfilling:)

Inject the trench with a water hose to help settle it once you have backfilled. Tamp, and let settle another week or so, and then revisit for a final tamping/cleanup.

What are you going to do with all of the extra soil. Particle size and structure looks really good. I'm guessing you havent had rain in a while?

White Gardens
11-30-2008, 08:38 PM
Looks good, have fun backfilling:)

Inject the trench with a water hose to help settle it once you have backfilled. Tamp, and let settle another week or so, and then revisit for a final tamping/cleanup.

What are you going to do with all of the extra soil. Particle size and structure looks really good. I'm guessing you havent had rain in a while?

The dirt is a medium grade, highly erodible top soil. It was, and I say was, fairly dry until we got 6 inches of snow last night and today.

The dirt is going to build a berm in front of the area that I trenched along the garage. I think in Pic #1. It's going to help divert some of the surface water away from that corner.

The trench is going to be compacted as I fill it. I'm just going to use my sledge hammer every 4-6 inches of washed gravel.

txgrassguy
12-02-2008, 02:50 PM
Everything sounded okay until you mentioned fabric across the top of the pipe or trench.
Fabric is bad news as it will clog and "blind" the drain.
Remember that 4" corrugated pipe is smooth on the inside and fines/soil that migrate into the drain can easily be washed out to the collection basin.
In fact my crews are currently installing over 700 linear feet of corrugated perforated and solid pipe to drain a property prone to flooding during a rain event.
The work pays well too, $4500 just for the drain work.
Provided I can get my camera to function properly I'll take some photos.

White Gardens
12-02-2008, 08:19 PM
Everything sounded okay until you mentioned fabric across the top of the pipe or trench.
Fabric is bad news as it will clog and "blind" the drain.
Remember that 4" corrugated pipe is smooth on the inside and fines/soil that migrate into the drain can easily be washed out to the collection basin.
In fact my crews are currently installing over 700 linear feet of corrugated perforated and solid pipe to drain a property prone to flooding during a rain event.
The work pays well too, $4500 just for the drain work.
Provided I can get my camera to function properly I'll take some photos.

Do you think I should line the trench with fabric and not cover it, or not put in any fabric at all. the suggestions for this fabric is to put it on top of your backfill and put soil on top of it. I'm going to have to wait another 3-4 days for the snow to burn off to finish it.

Now I'm confused on what I should do.

EagleLandscape
12-02-2008, 08:32 PM
you need fabric where you are using rock. or else the soil will fill in the pore spaces between the rock, thus eliminating the unique characteristic of the rocks ability to carry water easily.

txgrassguy. thats only $6.40 a ft. are you using rock in that as well? or is it just solid drain pipe? we charge 10' ft for drain with rock minimum.

White Gardens
12-02-2008, 08:57 PM
you need fabric where you are using rock. or else the soil will fill in the pore spaces between the rock, thus eliminating the unique characteristic of the rocks ability to carry water easily.

txgrassguy. thats only $6.40 a ft. are you using rock in that as well? or is it just solid drain pipe? we charge 10' ft for drain with rock minimum.

Ya, I'm going to use fabric over the whole thing then, I want rock all the way to the surface to help create a good drain field.

EagleLandscape
12-03-2008, 12:14 AM
well, you want to place soil for like 4" at the top. you don't need to have the rock exposed. it will look ugly, and it will become hard to maintain. wrap the fabric over the top, and cover with 4" of soil.

White Gardens
12-03-2008, 09:05 AM
well, you want to place soil for like 4" at the top. you don't need to have the rock exposed. it will look ugly, and it will become hard to maintain. wrap the fabric over the top, and cover with 4" of soil.

Thanks, I was thinking that. In the area next to the house and garage is going to have mulch put down, so a couple inches of soil and a couple inches of mulch should do the trick. the rest of the run is in the driveway, so putting rock over my fabric won't be a big deal.

Thanks for your help. I've been 90% positive on how I wanted to do this project so it would last for many years, thanks for helping confirm my initial instincts on how it should be done.

This project is 100 feet and I'm charging around $2700, that's including 3-4 yards of mulch and the removal of the 4.5 tons of rock to get started.

txgrassguy
12-03-2008, 09:33 AM
John, the trenching was at $6.40 a foot with corrugated 4" solid and perforated pipe (per my design) as back filled with concrete sand. The site is comprised of mostly sandy soils (located on the shores of a lake)and extremely easy to trench.
The grading, repair to existing septic system, and the installation of a five station irrigation system is all extra.
Right now the job has already experienced two change orders taking it from $9,800 to approaching $11,500 with a finish time of three more days.
Total out of pocket expenses including all equipment rental, labor, irrigation parts, etc is right at $4,189.00. Not bad for myself, two employees and five days of work.

White Gardens
12-03-2008, 09:31 PM
Ok, Here is what I decided.

The first 6-7 inches, including the 4 inch pipe is going to be pea gravel. My main concern is that the daownspout will fill the perforated pipe and leach out next to the foundation and garage. I'm hoping that the pea gravel will help keep the water in the pipe in low flow situations, but let water travel through it to the pipe.

Then the rest of the trench is going to be filled with a washed crushed gravel around 1 to 1.5 inch diameter/size. I'm thinking the the angular stone will help water travel down to the drain pipe with no problems as it doesn't pack as tightly as pea gravel does.

I'll take some more progress picks in the next couple of days. Besides, the landscaping side of Lawnsite is slowing down pretty good, so I like to post stuff if I can. :sleeping:

Tyler7692
12-03-2008, 11:39 PM
Why don't you use solid pipe by the garage?

qualitylandscaping
12-03-2008, 11:50 PM
We lay #2&3 Washed Stone Blend under the pipe. #2 Washed only on top of it. 4mil poly sheeting in a U shape covering the walls and base. Landscape fabric on top covered with driveway stone, mulch, or turf.

Pic #1- is the #2&3 Stone
Pic #2- is the #2 Stone (its about the diameter of a quarter)
NEVER use pea gravel or crusher run (limestone)..... Always make sure its washed, as you don't want any dust or fines.

White Gardens
12-04-2008, 12:12 AM
Why don't you use solid pipe by the garage?


There is water coming strait to that direction and I do believe that there is some ground seepage around that area too, so I'm trying to catch it if I can.

I wanted to use solid, but I discussed it with the homeowner and he wants the perforated pipe all the way.

White Gardens
12-04-2008, 12:15 AM
We lay #2&3 Washed Stone Blend under the pipe. #2 Washed only on top of it. 4mil poly sheeting in a U shape covering the walls and base. Landscape fabric on top covered with driveway stone, mulch, or turf.

Pic #1- is the #2&3 Stone
Pic #2- is the #2 Stone (its about the diameter of a quarter)
NEVER use pea gravel or crusher run (limestone)..... Always make sure its washed, as you don't want any dust or fines.


The problem I'm having with suppliers is that they are full of crap. I haven't found one company yet that has true washed stone, it's usually just screened. I called one place and they said there was no fines in their "clean" stone, and low and behold I go there and it's muddy. Then I get in an argument with the scale house guy and left.

I'm wondering if I'm going to have to wash the stone before I use it, even though the temps have been hanging around freezing here lately.

Thanks Steve,

I'm kinda wondering at this point though if I'm just going to be stuck with what's available. To me though, regardless, I am thinking of finishing this project the best I can. And I also figure if farmers have no problems just sticking corrugated, perferated pipe in the ground directly, and it works for years, then I'm ahead of the curve on this one, but, I am not justifying doing inferior work.

qualitylandscaping
12-04-2008, 12:22 AM
I'm assuming you're going to a quarry, not a garden center/ nursery?

Is there a Hanson pit close to you? (www.hanson.com). They have some of the best stone products I've ever seen.

If your only option is to buy crap with fines mixed in, it would be a good idea to wash it. Dump-spread it, go over it with a high pressure stream and kiss your profits goodbye.


Good luck

qualitylandscaping
12-04-2008, 12:25 AM
Have no idea how close this is to you, but may be worth a shot.

http://www.valleyviewindustries.com/products.htm

White Gardens
12-04-2008, 05:21 PM
Have no idea how close this is to you, but may be worth a shot.

http://www.valleyviewindustries.com/products.htm

I just got off the phone with these guys.

Unfortunately screened and not washed is only available. They also supply the local material yard in Bloomington, which is where I get most if not all fill type of materials and some landscaping rock. That is the place that I felt the 1-2 inch rock was muddy.

Thanks for all the help, that was some great piece of info.:clapping:

I think I'm going to have to just get the best product I possibly can and know that I have a good lined trench that shouldn't get any/little silt intrusion after it's done.

Here's a thought I had too. My dad has an old one at our farm and I was contemplating using it. This Pic is only a reprensentation. The one available to me is much older, sits at a 35 degree angle, simple electric motor, with a simple screen. I could just put it up to the back of my truck, shovel in one scoop at a time, and discharge into my wheelbarrow. I would love to be able to throw water onto the rock as it is screened, but, I would have to devise a way to cover the electric motor so water doesn't get on it.

http://www.productionsales.com/images/Neco.jpg

White Gardens
12-04-2008, 05:37 PM
Actually a little closer to this design.



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qualitylandscaping
12-04-2008, 11:22 PM
There has to be somebody that has washed stone! I found Valley View by doing a search on yellowpages.com for gravel in Bloomington. There were several other listings, VW just caught my attention b/c they had a website listed.

Or do a google/yahoo search for the same. I honestly can't believe there isn't anything out there.

EagleLandscape
12-04-2008, 11:37 PM
just buy pea gravel, it will be fine.

yes, quality is right, someone is going to sell that stone. i doubt there is not a yard available within 50 miles or so. unless you live in the boonies.

White Gardens
12-09-2008, 05:05 PM
So, after a lot of calls, and cold, then warm, then frozen ground, I'm about done.

Luckily I was able to get the driveway section done today so they can actually park close to the house again. I used a large simplicity garden tractor with a bucket to remove my pile of mud/frost/dirt over closer to where I'm going to build my berm towards the front of the house. Unfortunately, it was raining, so I couldn't drive up any closer to the exact area as I would have liked.

I did get the trench filled first. The drainage pipe is encased by 4-6 inches of pea gravel, and the rest of the trench is filled with CA-11. Basically it's CA-6 without the gravel dust. It was fairly clean, angular, and the best I could come up with after talking to suppliers the last 4 days.

I couldn't tell you how many times I heard, " Just use pea gravel ", or, " You don't need fabric if you have a silt sock ".:hammerhead:

Oh, the kicker. I broke the tip of my left pointer finger when I was hammering nails to hold my fabric in the frozen trench. Not a glancing blow either. Full Swing, hand at the end of the handle, and square on the finger nail. I almost passed out.

EagleLandscape
12-09-2008, 08:33 PM
glad to know its getting done.

pea gravel will hold more water... just fyi:) the smaller the particle size, the more water it can retain.

White Gardens
12-09-2008, 10:45 PM
glad to know its getting done.

pea gravel will hold more water... just fyi:) the smaller the particle size, the more water it can retain.

I took that in consideration. That is why I used it around the pipe. I figured the pipe will be able to retain some water and get it moving down the drain, rather than moving into the pipe and leaching out where I didn't want it to.

The CA 11 is angular, shouldn't hold any water, so it should allow any water to seep downward towards the pea gravel and drain pipe.

I've thought long and hard about it, I'm trying to not have any issues when it's done. I also considered using solid pipe around the house, but the homeowner didn't want it.

Now, if I could only get my wife to think about something long and hard.:laugh:

EagleLandscape
12-09-2008, 11:31 PM
Haaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

GAmower
12-20-2008, 02:43 AM
In our area the downspouts have to be solid all the way out (to your rock pit, city drainage system) and a second line of perforated pipe for the perimeter drain. All PVC non of the big O products. I is easy to rotorotter later if you have a problem.
J

midsouth grass master
03-07-2010, 07:52 PM
Hate to post this as its too late to help, but angular rock actually compacts very tightly and has the least pore space. Round rock will not lock together and this prevents it from compacting and thus leaving pore space for air and water. I worked in a soil testing lab in college and we frequently tested sands for these characteristics. Think of two triangles placed opposite one another and arranged in opposing directions... notice they lock together and fit like a puzzle. Butt 2 circles together and notice the difference and available pore space above and beneath where the outside diameters touch. Angular rocks and sand are only desired for construction where they are used in foundations and road bases. Hopefully this will help you next time.

Dave88LX
08-12-2013, 01:36 PM
So what is the consensus about fabric over the top of the drain? I'm at the point right now in mine where I need to decide if I want to fold the top of the fabric over, or, get rid of it. FWIW, in this area, I am going to have crushed stone all the way up to the surface.

White Gardens
08-12-2013, 01:55 PM
So what is the consensus about fabric over the top of the drain? I'm at the point right now in mine where I need to decide if I want to fold the top of the fabric over, or, get rid of it. FWIW, in this area, I am going to have crushed stone all the way up to the surface.

Cover it over as tight as possible.



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Dave88LX
08-12-2013, 02:13 PM
I'm confused...

White Gardens
08-12-2013, 02:35 PM
If you can line the whole trench with fabric, then cover it over, then that is the way to go.

If you can keep your trench as covered as possible, then it will extend the life of the drain by keeping as much silt and debris out of it.


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Dave88LX
08-12-2013, 03:18 PM
I got you now. My concern is silt and debris sitting on top of the fabric and blocking it that way. Is that a concern, or, how is that alleviated?

whiffyspark
08-12-2013, 03:23 PM
Rocks should be on top of the fabric as well rocks all around

Dave88LX
08-12-2013, 03:48 PM
Got that... So, as long as one takes care of their yard, they shouldn't have to worry about that junk falling through the rocks. :)

White Gardens
08-13-2013, 09:36 AM
I got you now. My concern is silt and debris sitting on top of the fabric and blocking it that way. Is that a concern, or, how is that alleviated?

In the case of this job I did, I just did a light layer of mulch over the top in the landscape bed and rock in the driveway.

Talked to the HO just the other day and they still haven't had any water in their basement. I think they had a tiny trickle earlier this spring when we had 7" of rain in a week and that was it.



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