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I work with ArcMap 10.1.

There is a proposed area for building a dam. I'm just trying to calculate the approximate volume of dam in different elevations.

I created a raster of area and also other several rasters with different fixed elevations (50, 75,100 ...) and tried to calculate cut and fill volume through this order. But after calculation, when I open the attribute table the numbers don't make any sense. I attached the picture of table.

I have these questions:

  1. Is this even a right way that I've chosen to calculate volume of a reservoir? If it is not how can I calculate it?
  2. How can I find out what is the unit of numbers that were given in attributes table (cubic meter?, cubic kilometer, 1000cubic meter?, ..)?

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closed as too broad by PolyGeo Mar 13 '17 at 5:39

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    What steps did you take to try to calculate the volume? – MaryBeth Dec 31 '15 at 19:38
  • I create TIN from contours. And Raster from TIN for dam area. And on the other side create a TIN with Fixed elevation For example 150m In cut&fill order used them on before and after requirements – Amir Arsalan Dec 31 '15 at 21:16
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Use a projected coordinate system suitable to your region. UTM is common for this. Those units appear to me to have been generated from:

x=decimal degree

y=decimal degree

z=your layer units such as meters.

So basically nonsense. Fractions of a degree / meter.

For this to make any sort of logic you need to:

  1. Convert the all to the same units such as meter (x,y,z) and put 1 in the z-Factor.
  2. Use actual units in x and y (not degrees) and then convert these units to 1 in the z units.

It is all here.

If the x,y units and z units are in different units of measure, the z-factor must be set to the appropriate factor, or the results will be incorrect. For example, if your z units are feet, and your x, y units are meters, you would use a z-factor of 0.3048 to convert your z units from feet to meters (1 foot = 0.3048 meter).

  • Tanks for responding. I create a pline in Civil D 2015 and gave it elevation manually. Next I added it to GIS. I didn't change any unit setting and the coordinate unit is UTM. I used (0.3048) as Z factor and the same numbers that don't seem to be volume of a reservoir showed up. – Amir Arsalan Dec 31 '15 at 20:29
  • Can you show me the screen capture in ArcCatalog that shows the coordinate is UTM and I should be able to help? I think it is not and Arc is viewing it as CGS 1983 – If you do not know- just GIS Dec 31 '15 at 20:32
  • How can I Set my projected coordinate system on UTM? Would you mind tel me step by step? – Amir Arsalan Dec 31 '15 at 21:10

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