Grindstone Lake Morphometry

The table below summarizes information about the Grindstone Lake basin. The lake has been "sliced" into layers, or slabs, of water that are 2 meters (6.5 feet) thick. The table reports the volume of each layer and the surface area at the middle of each layer. Adding up the layers yields a total volume of 46.9 x 106 m3 (cubic meters). The surface area of the lake was determined by GIS from the Landuse maps(lit cite) and equals 216 hectares (2.16 x 106 m2).

To estimate the area at the top of any layer, use the following formula: Regression of : Area (hectares) @ top of layer vs depth of layer top (meters) A(z) = (-5.1998)*z + 219.35.

To estimate the volume of any 1 meter thick layer, use the following formula: Regression of: Volume of 1m layers versus mid-layer depth (z) V(z) = (-0.5.181)*z + 22.158.

 Table 1 Morphometry of Grindstone Lake. Areas in hectares (1 hectare [ha] = 10,000 m2). LAYER (meters) AREA (hectares at mid-depth) VOLUME (x 105 m3) 0-2 216 43.053 2-4 212 41.271 4-6 201 39.191 6-8 191 37.111 8-10 180 34.031 10-12 170 32.951 12-14 160 30.871 14-16 149 28.791 16-18 139 26.711 18-20 128 24.632 20-22 118 22.552 22-24 108 20.472 24-26 97 18.392 26-28 87 16.312 28-30 76 14.232 30-32 66 12.152 32-34 56 10.072 34-36 45 7.732 36-38 30 4.872 38-40 19 2.792 Total Volume = 46.9 (x106 m3)

 Table 2 Complete depth profiles of area (at top of layers) and layer volumes for Grindstone Lake. Z1 and z2 refer to the top and bottom depths of a particular layer. DEPTH Z (meters) AREA @ top (hectares) LAYER FROM z1 to z2 (m) LAYER VOLUME (x106 m3) 0 216 0-1 21.638 1 215 1-2 21.378 2 212 2-3 20.895 3 206 3-4 20.375 4 201 4-5 19.855 5 196 5-6 19.336 6 191 6-7 18.816 7 186 7-8 18.296 8 180 8-9 17.776 9 175 9-10 17.256 10 170 10-11 16.736 11 165 11-12 16.216 12 160 12-13 15.696 13 154 13-14 15.176 14 149 14-15 14.656 15 144 15-16 14.136 16 139 16-17 13.616 17 134 17-18 13.096 18 128 18-19 12.576 19 123 19-20 12.056 20 118 20-21 11.536 21 113 21-22 11.016 22 108 22-23 10.496 23 102 23-24 9.976 24 97 24-25 9.456 25 92 25-26 8.936 26 87 26-27 8.416 27 82 27-28 7.896 28 76 28-29 7.376 29 71 29-30 6.856 30 66 30-31 6.336 31 61 31-32 5.816 32 56 32-33 5.296 33 50 33-34 4.776 34 45 34-35 4.256 35 40 35-36 3.476 36 30 36-37 2.696 37 24 37-38 2.176 38 19 38-39 1.656 39 14 39-40 1.136 Total Volume = 46.9 (x106 m3)