Enhancement of digital elevation models for overland flow network delineation in urban catchments

Abstract

Algorithms to prepare Digital Elevation Models (DMTs) for hydraulic analysis are common practice; these are often called DMT enhancement algorithms, and are frequently the first step of the analysis to extract overland flow networks from DMTs. In this paper, conventional DMT enhancement algorithms are tested to assess their effect on the generation of overland flow networks; the de_flat algorithm is also evaluated in this study. A sensitivity analysis of the generated overland flow network for different DMT enhancement algorithms is carried out and presented here. The results obtained so far suggest that this type of algorithms can be used to prepare DMTs for hydraulic analysis, but a great amount of care needs to be taken in order to avoid destruction of the terrain morphology. .

Prilikom primene Digitalnih Modela Terena (DMT) za hidrauličke analize, uobičajena je praksa da se koriste algoritmi za njegovo pre-procesiranje i poboljšanje, posebno kada treba odrediti mrežu površinskih tokova. U ovom radu se testiraju klasični postupci poboljšanja DMT-a i njihov efekat na generisanu mrežu površinskih tokova, kao i upotrebljivost de_flat algoritma. Urađena je analiza osetljivosti generisanja površinske mreže kanala na metode poboljšanja DMT-a. Dobijeni rezultati pokazuju da su testirani algoritmi upotrebljivi ali da se mora obratiti pažnja kako se tokom postupka poboljšanja DMT-a ne bi narušila njegova morfologija. .