Hydrological Modeling of Pashin-Lora Basin Balochistan, and Evaluation of Internally Generated Water Potential of it’s Built Check Dams

In recent years, Balochistan, Pakistan's largest province, has experienced droughts and floods, resulting in substantial infrastructural damage and loss of life.This study used geospatial and hydrological modeling to analyze the domestically produced water potential of the province's most water-scarce Pishin Lora Basin (PLB).The basin's hydrological characteristics were retrieved from the Digital Elevation Model (DEM), Landsat-8 images, and the Food Agriculture Organization's (FAO) soil databases.Rainfall data from the Quetta and Kalat stations were collected for the years 1990 to 2021 and used to simulate runoff in HEC-HMS software.Peak discharges for the wet and dry years were 5102.2 and 1095.8 cumecs, respectively, with annual runoff volumes of 5.82 and 1.25 billion cubic meters (BCM).The water potential during wet years can address water shortage issues if managed well and it will also help to develop appropriate strategic options during dry years to minimize the drought impacts in the region through watershed management.This study has further identified micro-watersheds of the constructed small/check dams for their annual runoff potential.Runoff volumes in wet years often exceeded their dam'azs holding capacities.That implied that small dams and other development schemes are not designed to incorporate seasonal variations.This notion was further confirmed when flood water topped over these dams during high runoff periods of the recent 2022 rainfalls.This study emphasizes proper planning of water resource development schemes.It highlights the repercussions of inadequately planned interventions.If the safety and sustainability of these structures throughout their design lives are to be warranted, they must be evaluated scientifically and modified accordingly.