Retaining Relative Height Information: An Enhanced Technique for Depression Treatment in Digital Elevation Models

This study presents an enhanced variant of the priority-flood based algorithm proposed by Wang and Liu for treating depressions in digital elevation models (DEMs). The redefines spill elevation, key concept original algorithm, as lowest that a pixel needs to have ensure non-ascending path toward border DEM, plus larger small number (~0.001) difference between unaltered values focal its immediate downhill neighbor. redefinition is adopted obtain intermediate surface direct flow ultimately carve DEM. Each carving starts from depression bottom propagates downstream until cell guaranteed Tests these algorithms on complex terrain 260,000 km2 Sichuan structural basin China shows maximally preserves directions extracts realistic drainage networks. Retaining relative heights, therefore directions, cells within allows new offer depressionless DEM with modification origin further hydrologic applications. treatment provided freely available tool BNUSinkRemv.