An alternative approach to estimate river cross-sections using LIDAR-based digital elevation model
Document Type
Article
Publication Date
4-1-2022
Abstract
Topographic LIDAR can be used to estimate elevation values for dry areas down to the river water level during the extraction of river cross-sections (XS). However, LIDAR cannot accurately predict the submerged topography, which causes uncertainty in river XS area estimation. This uncertainty affects the channel water level and flood inundation depth estimation in in situ sparse data. Therefore, an alternative approach is presented to estimate unknown submerged topography (UST) using topographic LIDAR. The one dimension/two dimension Hydrologic Engineering Center River Analysis System (1D/2D HEC-RAS) model is used to simulate the estimated river XS with the help of in situ river water level and flow data which is later validated using in situ data. The results show that the proposed approach accurately estimates water level (error >0.5 m), channel flow areas, and floodplain water depths. Notably, the extent of the estimated floodplain overflow by UST models was in 94% agreement with the real XS.
Keywords
Cross-section shapes, Digital terrain model, River cross-sections, Cross-sectional river area, Water level, Hydrological modelling
Divisions
GEOLOGY
Funders
Institut Pengurusan dan Pemantauan Penyelidikan, Universiti Malaya (GPF017B-2018),King Saud University (RSP-2021/351),Universiti Sains Malaysia (1001/PTEKIND/8011021)
Publication Title
Hydrological Sciences Journal
Volume
67
Issue
6
Publisher
Taylor & Francis
Publisher Location
2-4 PARK SQUARE, MILTON PARK, ABINGDON OR14 4RN, OXON, ENGLAND