There has been considerable discussion over the existence and genesis of Wonky holes. Pot hole like depressions have been identified on the continental shelf especially in the northern tropics where coral development is present. Some of these are located 20km to 40 km from the shoreline. Hand line fisherman have been targeting these owing to their high biodiversity, while trawler fisherman have been reporting net becoming snagged on these features. It has been postulated that these are due to submarine groundwater discharge from paleo channels and hence may act as possible pathways for contamination of the reef lagoons. Using radon and radium isotopes measurements alone may not be a reliable indicator of fresh groundwater discharge.
For nearly all of the alluvial groundwater flow systems in Queensland at the coastline, the groundwater potentiometric surface equated to sea water density, is marginally above mean sea level. It follows there is insufficient hydraulic head at the coast line to drive and maintain any submarine discharge that is located away from the near shore environs. This poses the question as to whether they are groundwater discharge areas. If so what is the source of this groundwater discharge and what conditions produce the required hydraulic head for discharge to occur. This paper examines plausible hydraulic head drivers for such phenomena and proposes alternative groundwater flow mechanism should groundwater discharge occur.