This appraisal of the Northern Adelaide Plains Groundwater Supply has been .carried out under the commission of the Director of Mines, South Australia. The appraisal is based on information compiled by the Department and re-produced in the appendices in the Department's Report entitled 'Northern Adelaide Plains - Groundwater Study (D.M.1974/67). Additional detail on pump tests conducted in Bore 331 was supplied to supplement that in the report. No attempt is made to examine the geological or geophysical conclusions which are accepted without reservation. The terms of reference for this appraisal are confined to questions of groundwater hydrology, particular attention being given to the engineering hydrology aspects. Specific points examined are: • Prediction of effects of future pumping or storage level. • Ability of aquifers to continue, to supply existing draft. • Physical characteristics of the various aquifers. • Likely Groundwater flow pattern. • Suitable management procedures. Although the conclusions reached have pertinence throughout the basin it is the area in the vicinity of Virginia that is examined thoroughly.