Flood inundation mapping and hazard assessment for mitigation analysis of local adaptation measures in Upper Ping River Basin, Thailand

Abstract

Floods have the potential to cause severe damages to humankind around the world. Similarly, the annual monsoon flooding phenomena have had devastating consequences on the Upper Ping River basin throughout the years. The current administrative structure for implementing flood mitigation and adaptation measures lacks effective utilization of locally available resources to provide comprehensive protection against flood-triggered devastation. That is why this study addressed this gap by conducting a flood hazard assessment at the sub-district level. The study assesses flood offsetting potential of local adaptation measures. A modeling approach was used that consists of developing the MIKE 11 and MIKE 21 hydrodynamic models for 1-D and 2-D channel conditions, respectively. MIKE 11 and MIKE 21 models were calibrated against observed discharge and water level (1D) flood extent (2D), respectively. Flood inundation and hazard maps were reproduced and categorized into several classes based on defined critical depths for 2, 5, 10, 25, 50, and 100 years return periods. The flood inundations reproduced on 601.8-996.9 km 2 (2.37-3.94% of total basin area) for 5-100-year return period floods, respectively. Based on flood hazard results, the "high hazard" category took first place with the largest flooded area, followed by "very high hazard" and "low hazard" categories, and the "medium hazard" category was ranked at last place with the least coverage of inundated area. To improve future flood protection, the existing administrative structure for flood adaptation and mitigation has to be updated based on an integrated flood management strategy.

A Review of the Application of Blue–Green Infrastructure (BGI) as an Effective Urban Flood Mitigation Strategy for Livable and Healthy Cities in Australia

“…Stormwater drainage systems serve as a necessity for the protection of people and infrastructure from sudden pluvial floods. Existing infiltration pits and pipe channels have a limited capacity for a sudden water load [27,28]. Small-to medium-sized networks of treatment facilities, pipelines, and pumping stations comprise the wastewater recycling constellation.…”

“…It is an environmentally friendly innovation, and it has benefited the world by reducing the cost of grey infrastructure and water treatment costs by improving air quality and groundwater replenishment [15]. Sorption and biosorption increase the groundwater's capacity and quality, absorbing heavy metals from polluted water [28]. It supports the processes of natural cycles and many more [37,38].…”