Build DEM / Surfer (.grd) surfaces & model layers from Google-Earth elevation, your X/Y/Z data, or an uploaded DEM · Hydro Geo Solutions LLP
Pick where the elevation comes from — the matching input appears below, then build the DEM / Surfer grid.
Grids the selected DEM (chosen in “Data source” below — Google elevation, your X/Y/Z, an uploaded DEM, or a DEM fetched for your AOI) and exports Surfer .grd, ESRI .asc and GeoTIFF for direct surface import into Visual MODFLOW Flex, plus model layers. Every download is named after the selected DEM.
Input points may be irregular or variable-density (rows/columns need not match) — the interpolation handles scattered data, and TIN honours every elevation exactly. The exported grid is uniform (Surfer/ESRI/Flex require it), so pick a cell size for your finest area of interest; Flex can still refine the model grid locally when draping this surface. Nodes outside the data convex hull are written as NODATA.
Grid B is resampled onto Grid A's mesh (bilinear), so grids with different cell sizes, extents or registration line up cell-for-cell. NoData in either grid → NoData in the result. Typical use: water table = Top (A) − DTW (B), with the clamp keeping it below ground.
Topography above = Layer 1 top. Define each layer's bottom by its own X/Y/Z data, a thickness below the surface above, or a fixed RL. All layers are gridded on the same geometry as the top and kept monotonic (no crossing surfaces).