The influence of the Land Use Land Cover (LULC) change on hydrological response in urbanized watersheds. Case study of Wadi Koriche and Wadi Kniss watersheds, northern Algeria.

The aim of the present study is to evaluate the impact of Land Use Land Cover (LULC) changes induced by urbanization on the hydrological response of the Wadi Koriche and Wadi Kniss watersheds, located in the urban area of Algiers (the capital of Algeria). Three land use scenarios were established by processing aerial and satellite images in three different periods (1959–1984–2019). These three scenarios were simulated with the flood of November 10, 2001, under the hydrological model Hydrologic Engineering Center-Hydrologic Modeling System. The results of this work show an increase in the built environment of 38% between 1959 and 2019 and a reduction in vegetation cover of 63%, accompanied by an increase in impervious surfaces of 48%, with an increase in runoff coefficients, a reduction in response times and water concentration times of the two watersheds, as well as an increase in peak flows of 30 m³/s and runoff volumes of more than 400,000 m³ between 1959 and 2019. The results indicate that LULC changes significantly impact the hydrological response of watersheds. They reduce infiltration and significantly increase runoff along the two wadis, causing flooding in the downstream parts of the studied watersheds. [ABSTRACT FROM AUTHOR]