1 Analysis of rainfall and runoff of a catchment area using HYMOS

The primary source of water in India is rainfall which is experienced over most part of the country. The rainfall varies from place to place and is measured using more than 3,000 rain gauge stations, which are set up by Indian Meteorological Department (IMD) and Water Resource Department of State Government. The average annual rainfall of India is about 119.4 cm. According to Irrigation Commission of India, the total annual average precipitation in India is about 4,000 km3, which contributes towards a total annual surface water flow of about 1,869 km3 and the remaining is lost as evaporation, transpiration and infiltration. If the intensity of rainfall is more, it can cause hazardous flood leading to high casualties and property damages. To mitigate the floods, structural and non-structural measures are inevitable along with strong flood forecasting or early warning systems. This is possible when effective and scientific analysis of rainfall and runoff is carried out for a vulnerable catchment area. This chapter emphasizes the application of rainfall-runoff relationship and Unit Hydrograph in Flood Forecasting using a software tool HYMOS. The results obtained show good amount of accuracy and corroborate with site parameters. For calculation purpose, the data of catchment area serving Multipurpose (Irrigation and Hydroelectric) Project Pench in Maharashtra-Madhya Pradesh is used, and rainfall is calculated for full climatic station, Kamthikhairy (latitude 21°22′01″N and 79°11′37″E) with altitude 295.00 m using various climatologically factors and HYMOS tool. This will provide data for the planning, scheduling of different irrigation and non-irrigational projects, flood routing and so on of the region.