Why do the Loyalty Islands have little surface water?

The Loyalty Islands, which are part of the French overseas country of New Caledonia, lack surface water primarily due to the geological composition of the islands.12

These islands are characterized as raised coral plateaus formed of porous calcareous rock. Because this rock is highly permeable, it prevents the formation of surface streams, as water quickly drains through the ground. Consequently, fresh water on islands such as Lifou and Maré can typically be accessed only through wells or within caves.32