Groundwater Prospects in Hot Arid Zone of Rajasthan- Trends, Forecasts, and Strategies for Sustainable Management (A case study of Jhunjhunun district)

Abstract

Groundwater is an important source of water for meeting the major water demands of the present time. Its easy accessibility and reliable supply make it especially important. However, the precarious nature of groundwater, particularly in arid regions, demands serious analysis for future water management. More than 80% of total groundwater extraction is used for irrigation. Excessive use of groundwater has led to water scarcity in many areas. A study was conducted in the Jhunjhunun district of the western hot arid zone of Rajasthan, India, to examine long-term groundwater trends and forecast future groundwater scenarios for the years 2023, 2040, and 2050. Groundwater data from 8 blocks of the districts, comprising of 200 monitoring wells, from the period 1984 to 2020 were used for the analysis. The Mann-Kendall (MK) test and Sen's slope were applied for statistical analysis, while the ARIMA model was used for modeling the time series data and forecasting. The results of the Mann-Kendall test indicated an overall declining trend in groundwater levels across all blocks, with the most extreme decline observed in Buhana block (-42.44 m), followed by Surajgarh (-36.90 m), Udaipurwati (-32.8 m), Chirawa (-32.7 m), Khetri (-27.2 m), Nawalgarh (-26.3 m), Jhunjhunun (-18.2 m), and Alsisar (-5.8 m) block from the base year 1984 to the year 2020. The overall district reported a decline in the water table by 27.3 meters from 1984 to 2020. The ARIMA (0,1,0) model forecasted groundwater table levels of 66.6 m, 74.3 m, and 82.0 m for the years 2030, 2040, and 2050, respectively, compared to an average groundwater table of 50.76 m in 2020. The declining groundwater levels are attributed to the increasing cropped area and other water uses in the district. There is an urgent need to recharge groundwater in the district at appropriate locations and to adopt more water-efficient cropping practices for sustainable groundwater management.