Runoff modeling is a research area that focuses on predicting the quantity and quality of water runoff from various surfaces such as urban areas, agricultural fields, and natural landscapes. This modeling typically involves the use of mathematical equations and computer simulations to estimate runoff volume, flow velocity, and pollutant transport. The goal of runoff modeling is to help manage water resources, reduce flood risk, and protect water quality in a watershed. Researchers in this field often study factors such as land cover, soil type, precipitation patterns, and topography to develop accurate runoff models.