Study of Groundwater and Intrusion Zonation Conservation in North Bali Sea

Abstract The research aimed to find out whether geological conditions and groundwater basins in the study area, aquifer potential in the groundwater basin at the research location to determine the boundaries of seawater intrusion in the area, compile groundwater conservation zones. The seawater intrusion was an event of infiltration or seawater/saltwater infiltration into groundwater. The case of seawater intrusion was a problem occurred in the coastal area of Lovina. It was located in Northern Bali which was a highly developed tourist destination after South Bali. The method used in knowing seawater intrusion was to use the Wenner-Schlumberger Geoelectric method with Pro-Skill and Naniura geoelectric tools to obtain the resistivity value or the type of resistivity value of rock layers. The data is processed with Res2dinv software which results in the form of 2D subsurface resistivity images. The rock geologically consists of clay, sand, and Breccia which was Buyan Beratan Formation. Generally, this rock type has permeable properties or good in passing water. The geoelectric results measurements distance of 46 - 58 m with depths ranging from 3.32 to 6.27 m, having a resistivity value of 3.44 - 63.4 Ohm-meters, and distance of 7 m - 11 m with a resistivity 0.0102 to 0.839 ohm m. Wherein the criteria for resistivity rocks value affected by intrusion were 0.5 ?m - 30 ?m. The interpretation results indicated the presence of seawater intrusion in the Lovina Beach, Banyualit Village with rock resistivity values below 5 ?m. Keywords---geol, groundwater basin, intrusion trick, north Bali, resistivity, geoelectric intrusion, seawater intrusion.