Barn floor drain pipe - depth slope?

lhfarm · Jul 26, 2005

I had a floor drain and a cleanup sink drain put in my new barn floor. You can see the floor drain pipe in the attached picture. I will run solid pipe from the corner of the barn to edge of field (about 80'), which drops off quickly. How deep should I place the pipe and what is a reasonable slope? And since I am using my new BH to dig the trench, is there a trick to getting the slope correct while I am digging?

BTW, you can see the water line and electric line I placed in a trench last weekend. It was my first time using the BH for a trench. The trench was about 40' long and I used my 12" bucket. Thanks to the advice here, I was able to dig a trench that was amazingly level /forums/images/graemlins/grin.gif.

beenthere · Jul 26, 2005

With the drain line, I would have it drop at least 1" in 12', if mine. I also would place it in as straight a line as possible, or at least without any 45 or 90° elbows. That way I could run a tape through if needing cleaning.
For depth, I wouldn't be less that 12" just to avoid tearing into it with surface tilling, etc.
Sounds like you have the 'tricks' down to get a good ditch with the bh. /forums/images/graemlins/wink.gif A 12' 2x4 and a level will get a slope easily. Could even put a block on one end of the 2x4 to add the 1".

fig · Jul 26, 2005

Ihfarm,

Rule of thumb would be 1/4" of slope per foot. 80' run...1/4" per foot...you would be 20" deeper at the other end (drop off in field). You want it to be pretty consistant; and you need to put something like pea gravel or crush and run down to keep your pipe from sagging or setteling out too much when you back fill and things settle out on top too.

Fig

lhfarm · Jul 26, 2005

Now that I've boldly stated I can dig a level trench, guess I should figure out how to do a slope /forums/images/graemlins/blush.gif. So I dig a few feet and then drop a 2x4 with an appropriate block under one end to represent the slop and get the 2x4 level. Dig a few more feet and repeat the process - right?

Then do I lay down some gravel, lay the pipe, then cover the pipe with gravel?

Thanks,

riptides · Jul 26, 2005

How about shooting the grade with a transit or level?, it may already have a natural slope. Then you can dig a uniform depth to your hearts content.

-Mike Z. /forums/images/graemlins/grin.gif

lhfarm · Jul 26, 2005

( How about shooting the grade with a transit or level?, it may already have a natural slope. )
Don't own nor have I ever used a transit - but I know how to operate a 2x4 /forums/images/graemlins/grin.gif

Eric_Phillips · Jul 27, 2005

Before you start to dig, take your 2x4 and level and check the natural slope of the ground. If you have at least the 1/4" per foot slope just dig at a consistant depth. No transit needed. I have also tested things like this with some string and a string level. The trick to that is getting the string tight enough so it does not sag.

Eric

lhfarm · Jul 27, 2005

Good advice, thanks! I would really like to learn to use a transit. Some day I have a stock pond that I would like to enlarge. I can't believe the list of tools I need to acquire that I've made since getting this tractor (NH TC40DA).

beenthere · Jul 27, 2005

There are small sight levels that can be used pretty easily, and if rested on a pole, and aimed at another pole held by a helper, will give you the general slope.
I have the 6" yellow tube hand level shown here.
http://www.survey-equipment.com/catalog/handlev.html

You could put stakes in every 10' or so, and then use the hand level to get heights at each stake, and then plot the slope to figure out how deep your trench should be at each stake.

willfick · Jul 27, 2005

I don't have a level or transit, but the bucket and tube method (I use 100' of 1/4" tube and a two gallon bucket) is an easy way for one person to measure levels over a two hundred foot distance, accurate to as close as you can read a tape measure. Costs next to nothing. In the picture I've got a piece of string holding the tube to the bucket handle. I plan to upgrade to a clothes pin.
The water moves through the tube faster than you'd think; a second or two to settle out from several feet change in level.
Wm

lhfarm · Jul 27, 2005

( I don't have a level or transit, but the bucket and tube method (I use 100' of 1/4" tube and a two gallon bucket) is an easy way for one person to measure levels over a two hundred foot distance, accurate to as close as you can read a tape measure. ..
Wm )
Can you explain extacly how this works. Sounds like the price is right /forums/images/graemlins/smile.gif.

willfick · Jul 27, 2005

OK, I'll give it a shot.
Take a bucket near full of water.
Get a 100' roll of 1/4" clear plastic tubing. A couple of dollars at Lowes, Home Depot, etc.
Put the bucket some where so that the water level in the bucket is higher than anywhere you want to measure. Put one end of the tube in the water and secure it to the bucket. I had the one in the picture tied to the handle with string, a light clamp would be more convenient.
Unroll the hose to the first place you want to check and suck lightly on the end for a second. The water will, quicker than you think, syphon to where you are.
Hold the end of the hose up and the water will stop perfectly level with the water level in the bucket. Tape measure or yardstick down to the ground. That gives you the ground or ditch bottom level relative to the bucket.
Then move the end of the tube to the next place you want to check, measure again, and in your head arithmetic will tell you the difference in elevation of the two spots.
Did I get that right?
When I built the spillway for my pond I used this to get the foundation right for the water level to be 8" below the top of a footbridge 150' away though the woods. Thirteen years later I'm still using the same piece of tube.
Wm
New bucket, though.

lhfarm · Jul 27, 2005

Great! /forums/images/graemlins/laugh.gif I'll give it a try and let you know how I do. Thanks again for all the advice.

willfick · Jul 27, 2005

Ooops.
I forgot the part that makes this slightly less than foolproof.
You have to be sure that the end in the bucket stays under water. If it catches air the instrument is not accurate. I think.
Anyway, if there's any doubt in your mind, you don't have to minutely check the length of the tube - just lay the end of the tube down and let the water run for a minute or two to clear any air out.
Good luck, Wm

jloppy · Jul 27, 2005

1/4 per ft is right on....but, remember that more slope is NOT better. By saying this, understand that waste water will have trash in it. If the slope is too much the water will outrun the trash, thus causing a clogged drain sometime in the future.

Good luck!

lhfarm · Aug 8, 2005

I finally got back on my drain project. I used the bucket and tube method to make a water level. From the point where I took the shot (~50'), there is a drop of over 11". I was really surprised. So I figure I can dig at a pretty constant depth and be pretty close to the proper slope. Just have to wait till next weekend to do the digging.

In case you are wondering why the drain doesn't run straight out from the barn, there is an old shed built into the hill, just out of view. So I had to run the line to the back of shed.

Thanks for the advice. I'll post the final results.
/forums/images/graemlins/grin.gif