The geology of the district south of the Murray between Cadell and Holder is described, with particular reference to the affect on the irrigation areas in terms of both creation and solution of drainage problems. The occurrence and nature of the "Blanchetown Clay" as the main shallow aquiclude is evaluated in some detail. Exploratory bores sunk to examine the main aquifer horizons in the Lower Miocene limestones are assessed in terms of suitability for drainage water disposal, and limited experimental work carried out to try and improve aquifer characteristics by chemical treatment is described. The report, reviews, in particular, the problems likely to arise in the recently established private irrigation areas and suggests, where possible, the most likely danger spots. Established drainage methods in the Waikerie Irrigation Area are noted and a general analysis of likely future requirements is made for guidance in planning new bores. Brief reference is made to the regional pattern of groundwater as it affects drainage of excess irrigation water.