Groundwater flows mainly through two major aquifer systems: a regionally unconfined aquifer, and an underlying confined aquifer. The two aquifers are separated by a low permeability confining bed (or aquitard). Determining the degree of hydraulic connectivity between the two major flow systems, and the mechanisms that control groundwater flow through the aquitard, are important in the assessment of the water resource of both aquifer systems, and ultimately in maintaining these resources at a sustainable level. This report investigates vertical groundwater recharge in a known recharge area to the confined aquifer. At two sites, a series of multi-piezometer wells were constructed: the first located about 10 km east of Nangwarry, the other about 5 km east of Tarpeena. At each site a profile of groundwater flow between the aquifers was created using hydrochemical, isotopic and hydraulic information. A conceptualised model of recharge to the confined aquifer was generated using these results in conjunction with regional data. It is inferred from carbon-14 and chlorofluorocarbon data that recharge to the aquifer at Nangwarry and Tarpeena is occurring via preferential flow (fractures, faults or sinkholes), rather than via porous media flow through the regional aquitard. Expansion of softwood, and more recently hardwood, forestry plantations may significantly impact on vertical recharge to the confined aquifer of these sites. Regional mapping of carbon-14 suggests that the recharge to the confined aquifer may occur in relatively small, localised areas, possibly controlled by preferential flow.