draining ditch..

[Mean Jean]

I had the same problem last year with a low spot.
I ended up installing a french drain as someone else suggested.
80 feet long and dug by hand.
Starts at 14 inches deep and ends at 25 inches deep.
Rule of thumb is drop roughly 1 inch every 10 feet.
Use 4 inch weeping tile.
Wrap tile in cloth and the another layer of cloth over the stone for backfill.
I wouldn't do by hand again. Rent a ditch witch for $80 a day.
I spend 3 nights just digging the thing.

 

[JB4310]

Actually, a water level is much more accurate than a transit or a rotary laser level.

I have a rotary laser because it is much faster and more convenient in many situations, but a water level is more accurate and never needs calibration.

The few projects where I have considered hiring a contractor I will ask them about water levels and if they claim that their expensive laser is more accurate, they do not get the job. They just do not have the engineering skills I want.

There can be no arguing with water, it's the basis of all spirit levels.

That's why I often recommend people use the water from what ever problem they are trying to correct, to aid them in the solution. Whenever I dig a drainage trench that has minimum percentage of pitch due to topographical limitations, I flood the trench to make sure it will work once the pipe is laid in.

The water level in the link does not look like a construction grade precision measuring instrument. For it to be accurate the containers on each end would need to be leveled independently or have precise markings around them so the water in them could be used to level them. Or do they just use the top rim?

This of course is splitting hairs, cause almost any type of "everyday" construction has a tolerance of +/- 1/4"

I agree with you in principle/ fact, the longer tube of water is going to be more accurate than the little bubble in a 1 inch tube. But that's pretty harsh sending the contractor home cause he's not familiar with a primitive water level I've never seen one used in construction, I have seen water filled hoses used to level ships in dry dock.

JB.

 

[CurlyDave]

...But that's pretty harsh sending the contractor home cause he's not familiar with a primitive water level I've never seen one used in construction, I have seen water filled hoses used to level ships in dry dock...

I just didn't hire any contractors who couldn't understand the primitive science behind a water level, but who thought their laser level was more accurate because it was expensive. Big difference between sending someone home and not hiring him in the first place. I want a contractor who understands that his high school physics course applies just a much in the real world as in his high school class. There are guys like this in the business.

I used to use water levels in construction frequently. Then laser levels came down in price, and I have a self-leveling one that is much faster. But, if it is really important, I still get out the old hose with two clear sections of tube on each end.

 

[JB4310]

I used to use water levels in construction frequently. Then laser levels came down in price, and I have a self-leveling one that is much faster. But, if it is really important, I still get out the old hose with two clear sections of tube on each end.



Well I said primitive, but how old can it be, how long has hose been around?

The concept of using water is very old, they probably used some type of open channel filled with water and took elevation measurements off that ???

How do self leveling lasers work? do they use mercury ?

I have a little torpedo laser, but you still have to level it using the bubble. Bought when they first came out several years ago, has come in handy for certain jobs. Cost around 200. back then, they probably give them away now.

JB.

 

[CurlyDave]

How do self leveling lasers work? do they use mercury ?

No mercury, they have an optical system suspended from a pendulum-type bearing.

I now have a Bosch, which can be calibrated. I used to have a Johnson Controls one that had no calibration, but it was stolen. Don't know if it didn't need calibration or if it just didn't have it.

They all come with some kind of a laser detector, which means they can be used outdoors, the detector will "beep" when the laser hits it even if you can't see the laser beam.

 

[JB4310]

Well this raises an Abstract question in my mind. What is level? a straight line parallel to the surface of the earth?

It can't go on forever like a traditional line we learned about in elementary school geometry.

I know with larger construction projects like bridges, the curvature of the earth has to be figured in.

How would that water level work over a long distance? would it be a straight line or curved with the earth? I suspect curved.

JB.

 

[CurlyDave]

You are right, it would be curved over very long distances.

 

[Egon]

How would that water level work over a long distance? would it be a straight line or curved with the earth? I suspect curved.

Best also add in atmospheric pressure as well as gravitation force to the question JB.

 

[JB4310]

I guess you could draw a straight line between the two ends of a miles long water level, but the only place it would be truly level would be at the center of the line. The further you went away from the center the less level it would be. Seems pretty basic, does that sound right?

JB

 

[bcp]

I've never yet had a project in which I had to account for the curvature of the earth.

Bruce

 

[beeforty]

I've never yet had a project in which I had to account for the curvature of the earth.

Bruce

I don't want a project that big either. I have enough trouble finishing the ones on my own 2+ acres:laughing::laughing:

 

[HunterWare]

Over any large distance the problem would be compounded by the fact that gravity differs measurably as you move over ground. This happens with elevation changes, but also over even ground due to density changes in the ground beneath. One can google "Gravity Map" and see... Not that a water level is really useful on these scales, but still interesting.

 

[LoveTheSmellofDiesel]

Came across this video based on the above info, good info. Was looking to see how to use it for drainage slope.

YouTube - How to Build a Water Level

 

[CurlyDave]

Over any large distance the problem would be compounded by the fact that gravity differs measurably as you move over ground. This happens with elevation changes, but also over even ground due to density changes in the ground beneath. One can google "Gravity Map" and see... Not that a water level is really useful on these scales, but still interesting.

If you are really worried about gravity variations, a water level is far superior to a laser level for a drainage ditch. The water in the ditch will always flow in the direction the water level indicates...

 

[HunterWare]

By the time earth curvature was introduced into the discussion of how to lay your drainage ditch I figured we had well moved into the realm of intellectual curiosity and away from practical considerations. One doesn't mark off levels for several kilometer intervals with a water level and that is the scale you are talking about when you are talking measurable (in relation to ditch depth or the size of a mere pebble in said ditch) earth curvature or gravity shifts.

Water levels are, of course, pretty handy for figuring out how you want to cut a ditch through a field and ground clutter.

 

[JB4310]

Well as far as the original problem goes, like I mentioned, I would use the water in the flooded ditch to show me exactly what to do.

Just get in there with some rubber boots and a grub ax and start cutting a channel. if it's pretty obvious what needs to be done, leave it diked in one spot so you're not always working in mud. then when you think you are close, open it up and let the water flow. it'll show you what else may need to be done.

I approach every water control situation with "the lowest common denominator" mentality. wasn't trying to complicate things

JB

 

[dave1949]

Well as far as the original problem goes, like I mentioned, I would use the water in the flooded ditch to show me exactly what to do.

Just get in there with some rubber boots and a grub ax and start cutting a channel. if it's pretty obvious what needs to be done, leave it diked in one spot so you're not always working in mud. then when you think you are close, open it up and let the water flow. it'll show you what else may need to be done.

I approach every water control situation with "the lowest common denominator" mentality. wasn't trying to complicate things

JB

That's just too much common sense :thumbsup: I have done the same, depending on the soil type, saturation, working in a puddle, can make the digging easier.
Dave.

 

[NormL]

notme seems to have disappeared for the last three weeks. I wonder if he got 'er done? I'm curious because I have a situation with some parallels to his. I'm hoping he comes back with the method he used and it's effectiveness. I have a 10 acre farmyard with numerous low spots and is generally shaped like a bowl in that melt and rain water gathers rather than flows away. Think mosquitoes!! The soil type is HEAVY clay and virtually waterproof. I have some swales but more are needed. Once I have the backhoe I hope to make some trenches and either lay drain-tile or backfill with stone. Thoughts?

 

[SixHoeBob]

If someone showed up on my project with a water level, I would laugh at them and then insult them until they left. On one hand we are talking about theoretically getting the pipe to the absolute correct grade, on the other hand it has been suggested to use black corrugated pipe. The black pipe is near impossible to work with. I doubt many can get PVC as perfect as the water level discussion implies.

My $2300 Rotary laser is more accurate than any project requires, and it will do slopes up to 10%.

The holes always go down. If you put the holes up stones will get in the pipe.
The low position for the holes allows the water to enter the pipe as opposed to standing in the stones.

Filling the low area without installing the drainage pipe first will result in a
reoccurring swamp.

 

[andrewy]

Has anyone had any experience with this stuff?
http://www.ndspro.com/drainage-systems/french-drains/ez-drain-french-drain/

It's a slotted corrugated pipe with a synthetic aggregate surrounding it, and the whole thing is covered in a geotextile sleeve. The manufacturer claims it is cheaper than pipe + gravel (when viewed as an installed system) , and I can believe it. It looks like the consumer version is available by special order from lowest and home depot for around $45/10 ft.

AndrewY