In an area covering parts of three Hundreds in Northern County Cardwell, the groundwater underlying the sandy heath terrain occurs at a depth varying from 9 to 80 feet. The groundwater has a gradient on the hydraulic surface of 1:5,000 towards the sea, into which it presumably discharges. The penetration of rainfall directly into the deep sand in wet winters is about thirteen feet, and does not effectively recharge the aquifer. Local recharge can only occur if the rainwater is added to by surface runoff. Stock water is available in some areas only, and owes its occurrence to the accumulation and downward penetration of surface runoff to reach the water table beneath the low lying flats. Any type of land development which may prevent or severely restrict local runoff will eliminate a source of good quality intake to the groundwaters. Subsequent pumping and use for stock would then cause the volume of usable groundwater to decrease and deteriorate to the point where stock water might no longer be available.