Exploration of Groundwater Resources in Mauna Kea, Island of Hawaii

Though fresh water is an especially precious resource in an island setting, the hydrological systems of Hawai\u27i are not well understood. In order for Hawai\u27i to progress towards self-sufficiency, its inhabitants must understand the resources available--including water. The Hawaiian hydrological model used to explain most aquifer settings in Hawai\u27i describes two systems: a dike-impounded system and a freshwater-lens system. The Humu\u27ula Saddle Region on the island of Hawai\u27i is located between Mauna Kea and Mauna Loa (two major shield volcanoes). A recent drilling project took place in this area, and researchers found two perched bodies of water located at 500-540 ft. and 700-1,181 ft. below the surface. Various characteristics were analyzed and compared in each of the sections. The saturated area closest to the surface contains very weathered materials (especially near the bottom of the saturated region) and is considered to be a perched aquifer. The second saturated region is a perched aquifer with several dikes that may be impounding water above. Near 1,181 ft. depth however, there is no dike but there is a layer with low permeability. This low permeability layer may have formed due to the level of fracturing, amount of weathered materials, and presence of clay in the area. These observations can help to build understanding regarding the formation of these aquifers and the limits of the Hawaiian freshwater systems