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3.4 Proposed Options Four main options were identified to address the shoreline certification issues in this area, specifically with regard to the location of the shoreline. Each of these options has advantages and disadvantages. It should be remembered that the difficulty in developing options is partly due to the past subsidence in the area that allows the ocean to interfinger with current development. It should also be noted that these options were originally developed for the County to consider, but with the recent shift in the State policy on shoreline certifications, it is unknown the extent that the State will follow these options. The four options presented are: (i) use of the current county practice of surface connection; (ii) rely on an increased use of the vegetation line; (iii) use the transition from runup or wash of the waves to gravity flow; and (iv) set an arbitrary boundary such as the mauka edge of Waiopae road. 3.4.1 Surface Connection One possibility for the shoreline determination is to use the current practice of surface connection to determine the shoreline. In the past, the County of Hawaii has used a 2.8 high tide to determine the extent of inundation and then where a setback should be measured from. Now that the State will be actively conducting shoreline certifications, they have indicated that the surface connection is a viable methodology and that they will also use a 2.8 high tide as their main criteria. The surface connection methodology is technically valid since a rising high tide at Kapoho generally has little wave action under non-storm conditions. This is due to shallow areas being flooded and the height of a wave is depth limited. Thus a high tide at Kapoho will give a reasonable approximation of the maximum inundation during a year, absent very large storm waves. For many of the ponds found on lots mauka of Waiopae Road, and in particular the lots that were two rows removed from the road, it is very difficult to determine if the ponds have a surface connection to the ocean or if the water level was raised by tidal influence by subsurface connection. This could have an impact on the administration of the area, since submerged lands would fall under the jurisdiction of the DLNR while those ponds or water bodies that are simply tidally influenced should be treated as a wetland with jurisdiction under the Army Corps of Engineers. The difficulty in determining the status of many of the ponds is due to many factors. First, there is thick vegetative cover in many areas, which makes access and observations to the area extremely difficult. Second, many of the ponds are very large, and it is difficult to trace throughout the boundary of the pond, which may be on several properties, if there is any possible surface connections. Even a small channel can provide the necessary connection. Finally, owing to the undulating lava topography, a circuitous route is possible for a channel to link the pond with the 32