WRRCTR No. 32 A Hydrogeophyscial Survey from Kawaihae to Kailua-Kona, Hawaii

Abstract

Several geophysical surveys have been conducted over the coastline area between Kawaihae and Kailua-Kona for the purpose of locating the optimum sites for possible development of ground water from the basal lens. A low-level aeromagnetic survey over the area and an infrared scanning effort along the coast with surface verification provided general reconnaissance information. Audiomagnetotelluric and D. C. electrical resistivity profiles defined more detailed, local structures. The infrared scanning survey along the coastline did not reveal any thermal anomalies that are reasonably attributable to previously unknown outflows of brackish water of magnitudes adequate for currently anticipated commercial exploitation. However, the aeromagnetic and audiomagnetotelluric surveys locate four lines which are possible barriers to lateral movement of basal ground water. Due to recharge considerations, only two areas were identified for test drilling, and these lie at elevations of more than 1, 200 feet. The D. C. electrical resistivity profiling was conducted at an elevation of about 100 feet or less. Based on the resistivity data, three possible sites for test drilling are selected -- two are in the north near Puako Bay and the other is above the present Kona Airport. The anomaly suggesting this latter site has probably been adequately tested by the test well already completed mauka of the site.