Understanding the hydrometeorological characteristics and relationships in the semiarid region of Maharashtra (western India): implications for water management

Abstract

In spite of enormous investment for water harvesting in Maharashtra, the issue of water deficiency persist. Therefore, with the proper understanding of recent (1975–2014) hydrometeorological characteristics in the semiarid region of Maharashtra, the study endeavored to suggest management strategies to optimize the water resources. To understand the inherent characteristics of rainfall, runoff, dam storages and groundwater, statistical techniques including descriptive statistics, correlation, regression and Student’s t test were applied. The monsoon rainfall has notable control over the water resources. As the study region characterized by significantly low water availability with high variability which is accountable for higher frequency and intensity of drought, it should be prioritized while formulating a judicial plan for water management. The major rivers of Maharashtra follow the unimodal pattern of rainfall. Whereas the study area displays a peculiar character of the bimodal and unimodal regimes of rainfall and runoff, respectively, this highlights the role of hydrological losses. However, it also indicates that there is a wide scope to harvest surface water, particularly during the months of September and October. Interestingly, the inter-annual variability in the extreme rainfall and runoff events over the study basins is observed to be higher in India. Most of the water (> 50%) received during flashy rainfall events drains out through flashy discharges. The impoundment of this water and modified irrigation schedule by considering the recent hydrological characteristics may diminish the variability and deficiency of surface and subsurface water. Furthermore, for the precise forecast of water availability in the study area, ENSO condition needs to incorporate, as it has a significant connection with rainfall and runoff.