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Finding contour - Resources Ontario

 
John Point
Posts: 9
Location: Ontario
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I couldn't find a thread about this but I assume there is one on here somewhere so please feel free to guide me there. I am pretty new to this and I  am finding the "on contour" part of permaculture the most difficult. How do you find the contour of your land? Is it as simple as using a site like this http://www.giscoeapp.lrc.gov.on.ca/matm/Index.html?site=Make_A_Topographic_Map&viewer=MATM&locale=en-US or do you need to hire a surveyor?
 
Adrien Lapointe
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Location: Kingston, Canada (USDA zone 5a)
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Depending on what you are trying to get done, the crude contour map you can find on the government's website can be sufficient. It can give you an idea of general positioning of elements. I find that the scale is too large in most cases to be really useful for my design. I tend to use it for context, meaning that it tells me where the water is going on the macro level. It will often help me determine if there are chances of runoffs from adjacent fields or if there is lots of seasonal streams going through.

I personally like walking the property to get a general sense of the contour. I can gather information like the orientation of the slope, the steepness, the ground condition (is it a wet or a dry spot), etc. That is a starting point in the design. You can then overlay that information on a map.

A simple A-frame is sufficient in most cases to finely position earthworks. I like to lay the earthworks following the keyline pattern and all I use is an A-frame.
 
Jack Edmondson
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Location: Central Texas zone 8a, 800 chill hours 28 blessed inches of rain
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John,

One can survey the land themselves easily.  There are many discussion here and elsewhere on the web of " A Frame " contour mapping.  The water level or " Bunyip " is another effective tool.  There are also many videos of how to use the newer rotating laser levels.  All work on the same principle.  Pick a spot, find spots that are level with the original spot, mark and repeat.  Soon the contour line takes shape.  The A Frame and Laser level are one person operations.  The water level usually takes two.  All can be done for under $500.  Much cheaper than a surveyor and accurate enough for land shaping.

                           
               


 
Adrien Lapointe
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My preference is the A-frame with a level attached to it instead of the the plumb line. The water level works but is really slow for my liking. I would only recommend getting a laser level if you know you are going to do many design.
 
Jack Edmondson
Posts: 233
Location: Central Texas zone 8a, 800 chill hours 28 blessed inches of rain
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John,

I forgot to mention, the reason for marking the contour lines oneself, most contour maps have a fairly large elevation change between contour lines.  My property has a slope of about 40 feet (12 meters?), which is the contour interval of the topographic maps published for my area.  On a map it looks level, but it is not.  Even a 'flat' piece of land has some contour, even if it is measured in inches of slope.  Hard to see with the eye, much less a map, but water will surely follow that slope. 

If you are doing any kind of water harvest or pacification, you will need to know even small gradients of slope across your land.  A map will not be nearly accurate enough for what we do.  The best way is do it carefully yourself.
 
dj niels
Posts: 181
Location: CO; semi-arid: 10-12"; 6000 ft
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I have tried using a water level, and also an A-frame level, but each time I try I get different results. Part of the problem is that I don't have a nice even turf.  My land is high desert. Each plant tends to be 2 to 3 feet apart, and the bare sand in between the clumps has blown or washed away, so I am dealing with a lot of humps and dips and can't get an even line. Anybody have any ideas for how to work around that?

My land has such a very gradual slope, it took me several years to even see that there was a slope. It is only about 6 feet -rough guess- in vertical difference between the highest point and the lowest point (on a 2 acre property).  I want to do some contour swales, but can't figure out the contours.
 
Jack Edmondson
Posts: 233
Location: Central Texas zone 8a, 800 chill hours 28 blessed inches of rain
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DJ,

Sorry to not respond sooner.  I wanted to give my answer some thought before I shot it out there.  Here is my take for your situation, which I see two determining factors.  Minimal slope and (relativity) easy to move soil.  I would not use the a frame.  What I would suggest is picking two points as far away from each other as you can measure.  Use a laser level or a long thin tube for your water level.  Pick 2 equal points on contour and mark.  Cut that in half with another point on the same elevation.  Then in half again, finding points on contour.  Use lowest level (depression) in the surrounding terrain when you mark all these points.  Trench indiscriminately from point to point after you are comfortable with your base measurements. 

You are not fighting a lot of slope or heavy clay soil.  You have more flexibility where you put the swale.  The top of the swale'e elevation does not mean anything.  It is only at the lowest level where water will settle that needs to be level to stop the water from seeking a lower level.  You can control that by trenching.  Sandy lose soil is easier to move.  Pick your line and shape the bottom of the trench to it (within reason.)

The biggest challenge I would see for your soil is how does water move across the landscape without soaking down into the sandy soil?  Are swales your best strategy to hold water?  Do you get a lot of run off?  Is the surface crusted which slows absorption?  How deep to bedrock or hard pan?  Also you need to stabilize that sand to keep your swales clean.  It sounds like you have a lot of wind erosion.  Until you can get roots into the berms you will need to mulch to keep the berms in place and the swales from washing in. 
 
dj niels
Posts: 181
Location: CO; semi-arid: 10-12"; 6000 ft
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Jack, thanks for those ideas. I will look into it more and see what we can come up with. Yes, we, my son and I, discussed the idea that maybe we don't have to be too picky on contour. I have not really seen any runoff on my land. I did once see some puddles, when I happened to be out there during a heavy rain, but the water usually soaks in almost immediately.

I have actually built several hugel beds, as close to contour as possible, in my zone 1 area, and have noticed that even though the raised beds do dry out and need to be watered more often, they help to direct the wind up and away from my planting beds on the terrace between the berms. But that takes a lot of wood and other organic matter for each one, so I have been considering trying to extend those berm lines into the outer zones, with swales that I might be able to get someone with a machine to help with.
 
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