Flood-prone ground
tr_flood_prone
What it does
Ground close above the drainage: height above the nearest stream (HAND) and the ground within a few meters of it, the first to flood when the streams rise (a terrain screen, not a flood model).
Like Height Above Nearest Drainage workflow (Fill + Flow Direction + Flow Accumulation + Con + Flow Length) in ArcGIS Pro and GRASS r.stream.distance (HAND) / SAGA in QGIS. Run by the product's terrain engine on 30 m cells from Copernicus DEM GLO-30 (full resolution): 740 x 930 = 688,200 cells; no model was called.
Flood-prone ground
Flood-prone ground (HAND up to 3 m above streams that drain 1.00 km2 or more): 69.817 km2, 11.3% of the area; 274 stream link(s).
Parameters
| Parameter | Value |
|---|---|
| cell_size_m | 30 |
Numbers
| Measure | Value |
|---|---|
| prone_km2 | 69.82 |
| prone_pct | 11.27 |
| hand_max_m | 3 |
| threshold_cells | 1,111 |
| stream_min_catchment_m2 | 9.999e+05 |
| streams | 274 |
| max_order | 4 |
| backend | pure |
| hand_median_m | 22.39 |
| unreached_pct | 3.262 |
| dem.rows | 740 |
| dem.cols | 930 |
| dem.cell_m | 30 |
| dem.crs | EPSG:32737 |
| dem.missing_frac | 0 |
| dem.elev_min_m | 1,562 |
| dem.elev_max_m | 2,456 |
| dem.elev_mean_m | 1,824 |
| dem.relief_m | 894.3 |
| dem_source.kind | copernicus |
| dem_source.native_res_m | 30.91 |
| dem_source.crs | EPSG:4326 |
| dem_source.dataset | Copernicus DEM GLO-30 |
Notes
- DEM: Copernicus DEM GLO-30 (open data; cached). Copernicus DEM GLO-30: produced using Copernicus WorldDEM-30 (c) DLR e.V. 2010-2014 and (c) Airbus Defence and Space GmbH 2014-2018 provided under COPERNICUS by the European Union and ESA
- the grid (30 m) is finer than the DEM (30.9 m): values between DEM samples are interpolated
- a terrain screen, not a flood model: no rainfall, discharge, channel capacity or defenses
Layers
Files
| Layer | Made by | Kind | Features | File |
|---|---|---|---|---|
| Terrain: Height above the nearest stream (m) | tr_flood_prone | raster image | PNG 596 KB | |
| Terrain: Flood-prone ground (within 3 m of the stream) | tr_flood_prone | raster image | PNG 47 KB | |
| Terrain: Streams (Strahler order) | tr_flood_prone | linestrings | 274 | GeoJSON 97 KB |
| Terrain: Flood-prone areas | tr_flood_prone | polygons | 232 | GeoJSON 203 KB |
