The study attempts to estimate the recharge to groundwater due to rainfall and irrigation using tritium tagging techniques in parts of Narsinghpur district under the Narmada catchment in Madhya Pradesh. The estimation of recharge to groundwater is crucial to better water resources management, particularly in arid and semi-arid regions.
In general, it is difficult to estimate recharge to groundwater from rainfall or irrigation using conventional methods due to non-availability of adequate data. Nuclear methods, especially tritium tagging technique has been used successfully in different countries including in many parts in India.
In the study area, experiments have been carried out in cultivated as well as in uncultivated fields. The area has mainly four types of soils, namely clay, clay loam, loam and sandy clay loam of which clay is predominant. The average annual rainfall of the area is 1246 mm. The percentage of recharge to groundwater varies from 12.22 % to 22.4 % in the study area with respect to the type of soil and other geohydrological conditions.
More specifically, the results obtained on percentage recharge at the experimental sites of Nayagaon, Bochhar, Mekh and Berheta are 15.59 %, 21.88 %, 18.08 % and 22.4 % respectively. The particle size of the soil samples collected from the sites reveal that the total percentages of silt and clay are 89.7 %, 88.1 %, 85 % and 77.4 % with percentage of gravel as 4.9 %, 1.6 %, 1 % and 2.4 % respectively. Therefore, the results are well comparable at these sites.
The percentages of recharge to the groundwater at the sites Supla and Surwari due to monsoon rains are comparatively low i.e., 12.22 % and 13.02 % respectively corresponding to the total percentage of silt and clay i.e., 91.1 % and 94 % respectively. However, if we consider the percentage of gravel at these sites, the values of groundwater recharge seem to be justified.
The report presents the details of the methodology followed as well as the details of the area.
Download the report here: