Urban hydrology is the branch of science, related to water management in urban areas. In cities, much of the land surface is covered by buildings and pavements, which do not allow storm water to soak into the ground. Instead, most developed areas rely on drains to carry large amounts of runoff from roofs and paved areas to nearby waterways. As more of the landscapes are covered with impervious surfaces, the amount of water that soaks in decreases, due to rapid run-off. In Kathmandu Metropolitan City (KMC), fast urbanization is adding built-up spaces very rapidly. City is losing a balance between impervious and pervious cover. Loss of greeneries and open spaces are causing rapid surface runoff and as a result, water recharge cycle is severely hampered. So, the book aims to study current run-off situation in KMC and its consequences. It follows two approaches - the technical approach, for estimating of current urban-runoff and the community based approach, to know the awareness level of the local people about urban-runoff and initiations from them to address the situation. From the analysis of both the above two approaches, the recommendations to minimize the runoff are proposed.