~ 185 ~ The Pharma Innovation Journal 2019; 8(12): 185-188 ISSN (E): 2277- 7695 ISSN (P): 2349-8242 NAAS Rating: 5.03 TPI 2019; 8(12): 185-188 © 2019 TPI www.thepharmajournal.com Received: 07-10-2019 Accepted: 09-11-2019 Shreya Nivesh Department of Soil and Water Conservation Engineering, College of Technology, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India Pradeep Singh Kashyap Department of Soil and Water Conservation Engineering, College of Technology, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India Bhagwat Saran Department of Soil and Water Conservation Engineering, College of Technology, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India Corresponding Author: Shreya Nivesh Department of Soil and Water Conservation Engineering, College of Technology, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India Irrigation water requirement modelling using CROPWAT model: Balangir district, Odisha Shreya Nivesh, Pradeep Singh Kashyap and Bhagwat Saran Abstract Present study deals with the determination of crop irrigation requirement of major cultivated crops in Balangir district, Odisha, India. The main crops include Paddy, Pulses, Cotton, Sesame, Groundnut and Mango. The irrigation water requirements and scheme water supply for each crop in the district were determined by using CROPWAT 8.0 model. Reference evapotranspiration was calculated using Food and Agriculture Organization-Penman Montieth equation. The effective rainfall was calculated using USDA S.C. method. Modelling results showed that actual irrigated area in the district is 17794 km 2 and net irrigation demand for the actual irrigated area is 0.9 BCM. This study might be useful to prevent over or under irrigation and planning water management strategies in the district. Keywords: CROPWAT, reference crop evapotranspiration, crop evapotranspiration, irrigation water requirement, effective rainfall 1. Introduction Over the past decade, many countries around the world have witnessed serious water shortages particularly in India. Population growth, Industrialization, extended drought, climate change and environmental concerns are the major limiting factors threatening food security in developing countries. Agriculture is the largest water consumer in India utilizing more than eighty-one percent water. Water for agriculture is becoming increasingly scarce in the light of growing water demands from different sectors. The need for increase in food production to match population growth is becoming a major concern to all the governments of the world. The dependence on water for food production has become a critical constraint to enhance food productivity. Irrigation practice, therefore becomes a most reasonable option as it is able to assist agriculture in areas with minimum rainfall and erratic rainfall distribution pattern. For better management of available resources and agricultural productions, it is necessary to understand irrigation water requirement and present level of water supplies. Methods based on ratio of irrigation water to cumulative pan evaporation (Aiyelaagbe and Ogbonnaya, 1996) [2] , open pan evaporation rate (Singh, 1987; Manjunath et al., 1994) [17, 11] and soil moisture depletion (Home et al., 2000) [9] have been widely used for scheduling irrigation. However, these methods are expensive and tedious. Food and Agriculture Organization recommend using CROPWAT software to better estimate crop water requirement. CROPWAT has been widely used for predicting, reference crop evapotranspiration, crop evapotranspiration, irrigation scheduling and cropping patterns (George et al., 2000; Andranistakis et al., 2000; Feng et al., 2007; Kang et al., 2009; Nazeer, 2009; Mimi and Jamous, 2010; Song et al., 2016; Tan and Zheng, 2017; Abirdew et al., 2019; Ewaid et al., 2019; Moeski et al., 2019) [8, 4, 7, 10, 14, 12, 19, 20, 1, 5, 13] . Hence in this paper an attempt has been made to compute irrigation requirement of major crops in the Balangir district and to develop scheme water supply under different management conditions using CROPWAT 8.0 model. 2. Materials and Methods 2.1 Study area The study area selected for the present study is Balangir Distict, also called as Bolangir district and situated in the western part of the state Odisha, India. The watershed lies within the geographical coordinates of 20 42 08.15 N latitude and 83 28 49.43 E longitude at an average altitude of 142m. Total geographical area of the district is 6790 km 2 and the average annual rainfall is 1290 mm. The total population of the district is 16.48 lakh and soil which are predominant in this area are Red and Black soils.