Global Mapper v25.0

Extracting volume data from water rise analsis

Hope this isn't too stupid of a question! I've created a surface from a lidar scan of a water basin (drained) that has an irregular shoreline and angle of repose. Also, the bottom surface is quite irregular as well. When using the water rise analysis, can you extract to volume at that level? Or do I need to create a surface and shift its elevation while calculating volume between surfaces? It would be cool if I could input a level change parameter like 1 decimeter and Global Mapper would spit out a csv : )

Comments

  • 946
    946 Global Mapper User Trusted User

    Create one contour line at the water level.

    Create an area from that contour and use it to calculate the volume.

  • Brilliant! Thanks for that. It would still be cool to set and increment and generate a csv with the level rise function lol!

  • Hi @X1aero

    Yes you can do exactly what you ask (i.e. specify a vertical increment, over a vertical range with results pasted to clipboard) under the Volume Calculation Parameter Setup as shown below.

    There is also an excellent forum posting on the subject here: https://www.globalmapperforum.com/discussion/15921/tools-for-calculating-volume#latest

    Hope this helps.

    Cheers,

    /al

  • 946
    946 Global Mapper User Trusted User

    I think that this solution will skip some area to be calculated as just by increasing the base height of initial area of interest, in the case of a basin, you will not take into account the horizontal increase of area.

    Something like in this print:

    or am I missing something?

  • No the above will work, I've just done it. I ran contours in the basin and picked the max water height by selecting highest closed contour. I turned this into a polygon, selected the polygon, from right click menu select Analysis/Measurement --> Volume - Measure Volume (Cut-and-Fill)

    Refer screen below, the base of the basin was 567 and top water level was 667. Step size 1m increments. The output file provided cut and fill volumes. Ignore the cut, but fill volumes are your volume. Also provides 2D fill area at said level (water area - handy for evap) and 3D fill area. Cheers,