Groundwater movement and management in tube-fed lavas

Sinking surface streams and large springs imply integrated underground drainage systems can sometimes exist within lava flows. Lava tube caves that contain underground streams have been reported from various parts of the world but various other structures are generally more important for groundwater movement. Complex fissured and conduit aquifers may result, but it is unwise to draw too close an analogy with karst environments. Nevertheless, there are some interesting comparisons to be made in relation to aquifer structure and function. Some aquifers in lava provide important water supplies that may be placed at risk of contamination if their potential vulnerability is not taken into account in management. Some field observations from Iceland, South Korea, Mauritius, Hawaii, Samoa and Australia are recorded.