This self-potential dataset has been acquired at Makapuu/Kaiwi Coast (Oahu, Hawaii, USA)in the frame of a Summer Class entitled "Hydrogeophysics in Volcanic Environments" given at the University of Hawaii at Manoa. The data helps understanding and mapping underground water circulations in this study area.. Self Potential survey for ‘Ike Wai aim at understanding underground water circulations in the coastal area and across the High-Low divide (Big Island) as well as in valley/ridge systems and across the natural hydrogeological “dams” (O’ahu). The objective is to enhance our understanding of ground water flows and aquifer depths in the areas studied. Combined with other datasets (seismic noise and Electric Resistivity Tomography), the Self Potential method gives valuable structural and geological information (faults, lithological transitions/interfaces, etc).the self-potential is a difference of electrical potential naturally occurring in the ground, measured between two electrodes placed at the surface of the Earth or in boreholes. SP can be generated by redox potentials associated with ore bodies or contaminant plumes that are rich in organic matter. A second source of self-potential anomalies is the thermoelectric effect associated directly with a gradient of the temperature affecting the chemical potential gradient of charge carriers. A third source is related to gradients of the chemical potential of the ionic charge carriers at constant temperature. A fourth source of self-potential signals is the streaming potential contribution related to the flow of the pore water relative to the mineral grain framework in saturated and unsaturated conditions.Basic corrections have been applied to all the datasets. Detailed analysis and interpretations are ongoing for Queen Lili`uokalani Trust (Big Island) and Dole (O’ahu) datsets.The data for each study site is stored in one Excel file composed of several datasheets. Each sheet represents one profile or part of a profile or a final table (tab found under the name TOTAL in each Excel file) containing data ready to be plotted or interpolated for maps. The sheets of a file are linked together and at this stage they should not be separated because they are connected together for the processing, and together they are used to create maps- Raw data for each profile within a study site is located in each sheet corresponding to individual profiles or sections of profiles- Names of participants to field surveys are detailed at the top of each excel sheet, in each excel file