Rainfall. Terrain. Perspective.

Flow arrows show the signed discharge on sampled links between model cells at the selected saved time. They follow the two grid-link orientations, sampled every 50 m with staggered positions. Equal arrow lengths show direction only, not speed or volume. Arrows are hidden where either adjacent cell is less than 2 mm deep or absolute unit discharge is below 0.000001 m²/s; no arrow does not prove zero flow. Directions update at two-minute saved intervals. They are solver outputs, not inferred from terrain slope or map colors.

Every scenario is calculated separately with Landlab 2.10.1 OverlandFlow, using a local-inertial approximation to shallow-water flow. Mapbox displays the actual survey orthomosaic and computed depth frames; it does not calculate water movement. Depth cells are reprojected with nearest-neighbor sampling for display. This is a plan view, without terrain exaggeration. Colors represent fixed depth intervals, not hazard categories; depths below 2 cm are transparent.

Uniform rainfall of 25, 50 or 100 mm lasts 30, 60 or 120 minutes, followed by 60 minutes without rain. Frames are saved every two minutes. The 100 mm options are hypothetical stress tests, not site-specific design storms or assigned return periods. All options use a 10 m grid, assumed Manning n = 0.05 and no infiltration. Real storms vary through time and space.

An artificial drained perimeter is used. Upstream inflows, culverts, buried drainage, pumps and tailings releases are not represented. Elevations are in meters. Survey quality documentation has been reviewed. The 10 m computational grid can omit smaller terrain and drainage features. Survey quality does not establish the accuracy of these hypothetical runoff scenarios. Apparent ponding can reflect missing drainage or terrain errors. Water remaining at the end is not assumed to have drained.

Both maps use the same elapsed time and fixed depth legend. If one run ends sooner, its water layer and metrics are hidden beyond its final frame; later conditions are not inferred. Pan and zoom are synchronized.

Numerical consistency does not establish field accuracy. The results are not calibrated or independently reviewed and do not replace engineering analysis. The two sites are not a controlled comparison of risk. AI assisted the software and presentation; it did not generate the water-depth values.

Original detailed viewers, including point inspection and grid/infiltration comparisons: Mining · Infrastructure. These retain the earlier scenario set.