Water Resource Management During Monsoon Months Based on SPI and CZI in Khordha District, India

Droughts took place because of decrease in amount of rainfall occurred over a large time period in a year or season. Management and planning of freshwater, which needs the understanding of historical droughts as well as their impact in the region, interpretation of the drought play a key role. Drought indices can be used for the forecasting as well as monitoring of the drought, as a result of which quantitative information about the characteristics of drought provided to the policy makers, which will be helpful for the planning as well as management of water resources. Therefore, this study was carried out in ten blocks (Balianta, Balipatna, Bhubaneswar, Jatani, Banapur, Begunia, Bolagarh, Chilika, Khordha and Tangi) of Khordha District to find the moderate, severe and extreme drought events using SPI and CZI, threshold limit of rainfall during June, July, August and September based on SPI and water resource management based on drought assessment. Monthly SPI and CZI indices are computed by using the 30 (1988–2017) years’ rainfall data. Maximum number of total (moderate + severe + extreme) droughts experienced by Banapur, Balipatna and Khordha, Balipatna and Bolagarh blocks in the months of June, July, August and September, respectively, are based on SPI calculation. Banapur and Balinata, Balipatna, Begunia and Khordha, Balianta and Balipatna and Bolagarh blocks detected with maximum number of total droughts are based on CZI. Rainfall threshold limit was different for different blocks in June, July, August and September due to the spatial and temporal variations of rainfall, and was found to be 89.3, 182.6, 188.4 and 137.4 mm, respectively, in Khordha District. If the rainfall occurred in a particular year below these threshold limits in monsoon months, drought will occur for that month in that year. Therefore, those blocks which were experiencing frequent droughts, water-harvesting structures can be constructed in those blocks. In addition to that, low water requirement crops can be encouraged to grow in those critical blocks.