Investigating changes in groundwater level in Kashan plain

Abstract

Aims: Management of water resources, especially groundwater in arid and semiarid regions, is of particular importance. Various natural and human factors in recent decades have created critical conditions for these resources. Therefore, this study was conducted to investigate changes in groundwater levels over the past 28 years. Materials and Methods: To conduct this research, statistics related to 64 piezometer wells were studied during the years 1990–2018, and the effect of rainfall and extraction from groundwater resources was interpreted and analyzed. Results: The results of the study showed that according to the hydrograph of 64 piezometer wells in Kashan plain, the groundwater level has a downward trend and has decreased by 15.29 m during 28 years. The annual drop was 0.54 m. An increasing peak of water table was also observed. Moreover, the water level has decreased slightly in some years and has not decreased in some years. Conclusion: The study shows that uncontrolled harvesting in the long run has had a more significant impact than rainfall on groundwater resources. Moreover, water abstraction has occurred on average in the southern and southeastern parts of the plain, which can be due to the concentration of agricultural lands in this area. To reduce this trend, strong management strategies should be adopted and appropriate to the situation.