How quickly would groundwater flow through rock with high porosity and low permeability?

Groundwater flow through rock with high porosity and low permeability would be relatively slow. While high porosity allows for a significant volume of water to be stored, low permeability restricts the movement of that water through the rock. Consequently, even though water can occupy the spaces within the rock, its flow rate will be limited due to the resistance posed by the rock's structure. Therefore, groundwater can take a considerable amount of time to move through such formations.