Water balance studies and strategies for combating water deficit in Upper Kolab catchment of Orissa

Analysis of water balance for Upper Kolab catchment was done according to Thornthwaite book keeping technique for six stations located within the catchment and for the entire catchment for the normal climatic year. On annual basis the catchment has a water need, rainfall, actual evapotranspiration, water surplus and water deficit of 1703.7 mm, 1479.82 mm, 1003.13 mm, 476.69 mm and 700.56 mm respectively. There is a water surplus from July to October and water deficit from November to May. The surplus months of June and part of July contribute to recharge the soil moisture deficit. The study shows the entire kharif season is deficit free and during rabi season the deficit amount is 455.88 mm. This deficit can be mitigated through low cost water harvesting structures, diversion of jhola water, in situ moisture conservation measures coupled with suitable agronomic practices. Though an average the whole catchment is under water deficit (700.56 mm), the agro climatic situation of the region is slightly moist (MI = 13.14%).