Impact of Groundwater Head Changes on the Permeability of Bedrock Aquifer‐Aquitard Systems

Abstract Understanding how groundwater level changes affect the permeability of bedrock aquifer‐aquitard systems is important for groundwater management, yet this relationship remains poorly understood. This study focuses on Tangshan in the northeastern North China Plain, utilizing tidal response analysis to investigate the dynamic interplay between groundwater level trends and permeability variations in bedrock aquifer‐aquitard systems. High‐frequency groundwater level data from two monitoring wells were employed to reveal a significant positive correlation: rising groundwater head leads to increased permeability of the bedrock aquifer‐aquitard system, primarily due to adjustments in groundwater head. This research provides direct evidence that both climate variability and human activities can influence bedrock aquifer‐aquitard permeability through changes in the groundwater head. The findings highlight the importance of integrating models of dynamic permeability induced by hydrological processes into groundwater resource management frameworks and hazard assessments, particularly in regions experiencing groundwater level recovery, such as the North China Plain.