Delineation of flood-prone areas using modified topographic index for a river basin

Abstract

The modified topographic index (TI m ) based on digital elevation models (DEMs) was employed to delineate floodprone areas in Mahanadi basin, India. TI m and flood inundation maps were compared to obtain the threshold (t) beyond which the area is assumed to be inundated by flood and the exponent of the TI m . Scale dependence was also investigated to evaluate the sensitiveness of spatial resolution of the DEMs. DEMs of five resolutions, namely, ASTER global, SRTM, GMTED2010 (30 arc-seconds), GMTED 2010 (15 arc-seconds), and GMTED 2010 (7.5 arc-seconds), were used and ASTER global was preferred due to its low error compared to the remainder. Flood frequency analysis was conducted to obtain the relationship between flood-prone areas and flood magnitude. It was observed that (i) the exponent in the TI m showed little variation, (ii) t is reduced with reducing spatial resolution of the DEM, and (iii) error is also reduced as the DEMs' resolution is reduced. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY 4.0), which permits copying, adaptation and redistribution, provided the original work is properly cited

Identification of Waterlogging-Prone Areas in Nanning from the Perspective of Urban Expansion

“…Rejouanul [60] used Landsat imagery to calculate the area of waterlogged in Sadekira County using a supervised classification method. Alternatively, the DEM topographic index was utilized to delineate waterlogging-prone areas in the Mohanadi Basin, India [61]. A multifaceted fusion of topographic, subsurface, transportation and meteorological elements was used to derive waterlogging-prone areas using hydrologic analysis [62].…”

“…A multifaceted fusion of topographic, subsurface, transportation and meteorological elements was used to derive waterlogging-prone areas using hydrologic analysis [62]. The study attributes waterlogging to a combination of topography, slope, water accumulation and land use [61,63,64]. Waterlogging management and resolution strategies focus on sponge cities, natural solutions, resilience concepts, and more [65][66][67].…”

Using geomorphologic indicators in preparation for flood zoning and flood risk maps in the Kashafroud basin, Iran

“…TI was modified and introduced as the modified topographic index (TI m ) (Manfreda et al, 2011). The DEM maps were examined with a spatial resolution of 30 Arc-S, 15 Arc-S, and 7.5 Arc-S to obtain the optimal threshold using TI m in the Mahanadi basin, India (Nagesh Kumar et al, 2021). Their results showed that increasing the spatial resolution of DEM maps causes increasing the accuracy of flood threshold.…”

“…The development of the geographic information system and remote sensing have led to the acceleration of production, processing, analysis, floods management, and high‐resolution spatial images of the Earth's surface (Demir & Kisi, 2016; Fu et al, 2020). The topographic index (TI) method uses Digital Elevation Model (DEM), soil moisture, and LULC for flood modeling (Nagesh Kumar et al, 2021). Increasing the spatial accuracy of DEM maps causes an increase in the accuracy of flood zoning and a decline in flood modeling error (Xu et al, 2021).…”