Irregular tessellated surface model map algebras to define flow directions and delineate catchments using LiDAR bare earth sample points

Abstract

ion that can degrade the data and compromise the quality of catchment boundary. Irregular tessellated surface models generate higher quality catchment boundaries, because the algorithms are devoid of additional data abstractions and transformations that degrade dataquality. Such catchments represent a more legally defensible delineation, and therefore may affect jurisdictional responsibilities with respect to water rights and other water resources-related issues. This thesis is divided into the following sections: a literature review, data sources, methods, results, discussion and conclusion. The literature review focuses on the LiDAR data 3 collection process and research into field of catchment delineations using raster-based surface models. The data section details the study area and data inputs. The methods section explaines the processing steps of ITSM Hydro, a Python-based series of algorithms that delineate flow direction lines and create catchment boundaries using LiDAR bare-earth sample points. The methods section also details the raster-based catchment delineation methods that used to compare and contrast the results of the Python algorithms and several different metrics used to assess rastersurface-model quality and quantify differences in area and shape between the tessellated surfacemodel catchment delineations and the raster-based catchment delineations. The results section contains maps of catchment delineations for four test areas, and the comparative metric results detailing the comparisons of catchment delineations for both raster and ITSMHydro methods. The discussion section highlights differences between the tessellated and the raster-based delineations, and the limitations and conditions of the ITSMHydro tool set. Finally, the conclusion and future work section is a discussion of suggested future enhancements and improvements to the tools developed for this research.