Shaping a baseflow model through multiple regression analysis: the Çoruh watershed example

Abstract

Abstract In today's conditions, where the frequency of events related to global climate change is increasing, it is important to employ water science to utilize water with maximum efficiency and to keep water under control in the areas close to its consumption zone. It is also important to determine how much of the flow in the stream during dry periods is the baseflow and how much of it is direct flow. This study designed a model of the baseflow index (BFI) and the baseflow rate (Qb) in one of the watersheds in Turkey. The smoothed minima method designed by the United Kingdom Institute of Hydrology (UKIH) was used to calculate the BFI and Qb at 10 flow observation stations in the Çoruh watershed. The Çoruh Watershed Baseflow Model was designed using BFI and Qb values with watershed characteristics and other variables. The determination coefficient of the BFI model was calculated as R² = 0.842, and the Qb model determination coefficient was calculated as R² = 0.99. The usability of the Çoruh model was proven by using the UKIH's smoothed minima method and comparing its relative errors with the BFI and Qb in the Çoruh model.