Groundwater resources, its mining and crop planning in Orissa, India.

Abstract

Groundwater being one of the most valuable resources of earth needs to be utilized properly for the healthy and economic growth of any region. The present study was carried out in Eastern part of India, where it is blessed with plenty of water resources but its utilization is very poor as compared to another part of India, which has been reflected through net cropped area, cropping intensity etc. Orissa, being one of the resource-rich States in India still struggles with low crop production and cropping intensity status. The groundwater development of the state is only 18.31 % out of total replenish able groundwater resources of 2100928 hectare meter (ha-m). Groundwater recharge being one of the most important components in the hydrologic cycle, it has to be estimated for any particular area before planning for any interventions. The natural groundwater recharge was only 22.31 % to 24.87% of the annual rainfall received in 30 districts of Orissa. The highest amount of recharge of 39.75cm was from Balasore and the lowest recharge of 26.47cm was in Rayagarh district of Orissa. However the estimation method was very crude as it is based on only rainfall of the particular area. More detail study on recharge aspects can be done under basin studies in the different region. Assessment of groundwater resources and planning for efficient use of groundwater in the agriculture sector has been planned based on crop water demand of each district of Orissa. The groundwater earmarked for irrigation is 1678038 ha-m. Considering crop water demand of 1030.5 mm (as per FAO 56 Penman-Monteith) during dry month period (November to May) the expected area to be irrigated is 1628372 ha. Since rice is dominated crop of this region even during rabi and summer season, another high-value cash crop through groundwater use is economically viable. For exploiting groundwater during rabi season, it is essential to know under-utilized and over utilized blocks of Orissa as the coefficient of variation was as high 133 % in Jagatsingpur district to as low as 1.43 % in Deogarh district. The groundwater development was a maximum of 77.61 % in Baliapal block in Balasore district. This block is dominated with summer paddy (January to April/May), which needs more frequent irrigation water for harvesting optimum yield.