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How do you survey lumpy ground?

 
Paul Overton
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A friend has a field with relatively little slope. He would benefit from gentle swales and other waterworks. But the surface is very lumpy; clumps of grass and six inch mounds of dirt all over. I had to drive across it in a hurry one day and it nearly shook the car to pieces.

An A-frame or water level is useless, I think. Where do you put one of the legs of the frame, or one of the stakes? On top of a lump of earth and grass? In its valley? Will it be possible to get true level anywhere without guessing?

I googled this but got no luck. I think A-frames/water levels are best for smooth surfaces but I don't know how to survey broken ground.
Lumpy ground.GIF
[Thumbnail for Lumpy ground.GIF]
 
Robin Hones
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My amateurish 2 cents....

The A frame will not work as the spread between the legs is fixed. Get a water level set up with a long tube that will give you the flexibility as to where to place the stake.

Measure the troughs not the hills. If you are surveying for swales you can always dig down, but you cant dig "up".
 
kevin downs
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You can find survey levels on ebay for $30 bucks or less. Find/make some tripod legs. It is just so much easier, especially when you have slopes, mounds, etc with a level. If you don't want to buy a level rod just get a 2 x 2 and a old measuring tape. It just makes things so much easier and quicker.
 
Paul Overton
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Robin Hones wrote:Measure the troughs not the hills. If you are surveying for swales you can always dig down, but you cant dig "up".


Thanks, but it still seems like I'm missing something; in the picture above (which of course is just made up) where would I put a swale? The pockets are usually just about a foot wide.

Or are you suggesting I remove the peaks and leave the valleys, and then do the surveying?
 
Tom Davis
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Bunyip Level would be my first suggestion.
Dumpy if you have more patience.
P.A. Yoemens, in Water for Every Farm talks about "tryiing to follow the remaining spots or areas of original surface or, if this is impractical, they should avoid all noticeably high and low spots."
He goes on to describe avoiding local wind blown high spots around shrubs and trees.
Also, the practice of "normalising" the line is discussed, where one does a second pass on the "contour" line where one uses pegs of a different color, and if the orignial peg is out of contour due to a localized high or low spot, you can adjust it higher or lower as needed.
Thus, you can produce a more uniform, better looking line of contour.
He also mentions, "The rule for Normalising"
High can go higher and low can go lower -- meaning a local high spot marker can move higher to compensate and a localized low spot can move lower to compensate. Buthe suggests using common sense.
If the survey peg is the front of your swale or contour feature, those local high and low spots will be covered by the dirt you dig out of the ditch
Anyway, check out his book pages 231-45.
Also, Simple Surveying for Farmers by Frank Debenham (mentioned is Yoeman's book, but I had to order from Aus seller. Out of print but not public domain yet.)
 
Paul Overton
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Matt, I am not quite clear on those instructions, can you explain?

Here's the same with a water level. Does he need to smooth the bumps? If not, where does the swale go?
Water level.GIF
[Thumbnail for Water level.GIF]
 
Tom Davis
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P.A. Yoemens, in Water for Every Farm talks about "tryiing to follow the remaining spots or areas of original surface or, if this is impractical, they should avoid all noticeably high and low spots."
I drew my first file to help explain, and tried to attach it, that didn't work. I use Open Office and permies.com wouldn't accept the file extension.
Then I tried to copy and paste, nope.
Then I used snipping tool, nope.
So, sorry, that's the best I can do now -- just try to follow the "original" surface, not the blown out, eroded/slumped whatever surface variations and "normalize" the line to smooth out those surface bumps.
No, I would not try to knock down every single hole and mound, that sounds like a lot of work.
All of that can be "smoothed out in the ditch.
Maybe just try building a small one, 10-15 feet long using whatever leveling method clicks in your head -- trial and error usually clears up a whole lot of "what-ifs" for me.
The level markers are the front of the ditch, throw dirt down slope of those markers.
And remember, it won't be perfect.
 
Paul Overton
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Sorry Matt, still not getting it. Guess I'm dense.
 
Tom Davis
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Maybe buy Water for Every Farm
Maybe my explanation stinks?
http://www.small-farm-permaculture-and-sustainable-living.com/land_surveying_basics.html
Maybe this helps
ftp://ftp.fao.org/fi/CDrom/FAO_Training/FAO_Training/General/x6707e/x6707e00.htm#9
 
Paul Overton
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The first link is helpful. It describes two methods of surveying which I think will work.

The second link is broken, could you attach it to this thread?
 
Paul Overton
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Nevermind. I was able to access the second link from Google's cached web page feature. I'd like to attach it to this thread but I can already tell that's going to be a pain. So for now, just search for the file name (e.g. x6707e01.htm) and clicked the "cached" copy.
 
Paul Overton
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I'm thinking a grid survey, with many samples (just a few feet apart), then input into a computer, and the values averaged out, should show where bigger swales could be dug. Thanks Matt for your help on this.
 
Paul Cereghino
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I think you might be trying to be too precise. The slope at the bottom of the swale produces water movement. The elevation between the bottom of the swale and the lowest elevation on the berm is storage. Your surveying is to define an approximate swale position, which is easiest as slope gets steeper. If you slope is so low and ground so irregular that you can't figure out the general orientation of the swale, you might not need a swale. Otherwise, you only need to design for storage and flow and not necessarily for a 'perfect contour'. I like the idea proposed to start the survey using all high spots, as the low spots are likely eroded or excavated... than even out your line if you like even lines or are using equipment, which finds advantage in even lines. If you are trying to move water around the site, focus on the finished grade on the bottom of the swale.
 
Sam Phillips
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Location: Tuscon, AZ
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Has anyone experimented with the mappir2 camera and drone? It's only $800 for the equipment but there's a $80 per month fee for the use of their cloud services. If you're just doing your property you'd only have to pay that once though and I could see it being worthwhile for as opposed to the cost of manual surveys in a consulting business if it works well. The videos on the site show the personal drones and cameras mapping agricultural fields but I could see this being very useful for a designer. Has anyone tried this? Thoughts? website: http://www.mapir.camera/
 
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