Within the Northwest Reserve, groundwater with salinities from 500-1500 ppm, occurs in three types of aquifers, unconsolidated Quaternary outwash sediments, broken and sheared basement rocks, and in the sediments of the Officer Basin. The Quaternary sediments constitute the most significant aquifer, and supplies from 300 to 900 eph may generally be obtained where the thickness of the sediments exceeds 80 feet. The bedrock aquifer involves difficulties in both siting and drilling, and too little information is available on the Officer Basin to assess groundwater potential. There at present 20 bores in the Reserve suitable for use, of which 10 are equipped. All known bores are tabulated and future groundwater development of the area assessed.