Twin Calamities in the Swat River Basin: Unraveling the Hydro Meteorological Drivers of the 2010 and 2022 Floods

Abstract

This paper presents a comparative evaluation of the hydro-meteorological factors underlying the regressive floods of 2010 and 2022 in the Swat River Basin, a climate-sensitive and topographically predisposed location in north-western Pakistan. The research examines, through the joint application of a qualitative case study method supplemented with GIS analysis, remote sensing, NASA MERRA-2 climate data, GlobeLand30, and hydrological modelling, the patterns, intensity, and effects of the two floods. The 2010 flood was mainly exacerbated by record monsoon floods that reached more than 300 per cent above average in some regions of Khyber Pakhtunkhwa, accompanied by La Niña and glacier meltwater flow, along with poor river dikes. However, unlike 2022, the flood was caused by extended monsoon rains and an intense pre monsoon heatwave, rapid glacial thaws, and rainfall as high as 243 per cent of normal. Analysis of land use indicated a greater extent of urbanisation, deforestation, and floodplain encroachment, which reduced the water absorption capacity of nature and thus increased risks. Although discharge peaks increased in 2010, runoff volume increased in 2022, due to enhanced hydrological responses. The study highlights the importance of reforestation, watershed development, flood zoning, warning systems, and hardy infrastructure in mitigating future calamities.