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Using another method such as a set datum, elevation or topography to determine the shoreline is ruled out in this study because it would require extensive changes at the statutory and regulatory level. Also, on-going subsidence would make the use of a set datum or elevation outdated after many years. Another difficulty would be the significant topography changes within the same property. The case can be made that the shoreline at Kapoho should not be determined by high tide events, but high wave events. Under the current shoreline definition, this would exclude storm and seismic (tsunami) events but not seasonal high surf from distant swells. Actually, under the definition both high tide and wave run-up should be considered. It was outside the scope of this study, but it is generally felt that high tide events are most useful for Kapoho area because wave runup is limited by wave height which is limited by the depth of water over Waiopae Road. Supposedly, further studies could have been conducted that made a comparison of high tide events with lesser tides coinciding with high non-storm surf. This was outside the scope of the study. Furthermore, the need to even do this illustrates some of the problems with the shoreline certification process. A thesis or dissertation should not be needed to determine the shoreline, because it only determines the baseline from which other 15 regulatory or development standards apply (e.g., the setback). 3.4.6 Waiver The Hawaii County Department of Planning could also use their power of waiver, under their SMA rules. Under Section 9-10(B)(9) – A shoreline survey (is required) when the parcel abuts the shoreline, except that the Director may waive the submission of the survey when the proposed development is clearly and unmistakably located on a shoreline parcel at a considerable distance from the shoreline. It could be argued that the areas mauka of Waiopae Road subject to flooding by gravity flow are a considerable distance from the shoreline. Also under the Hawaii County shoreline setback rules, Section 11-4(c) the Planning Department may waive the certification requirement in cases in which there may be unusual physical circumstances or conditions of the land. The case can be made that these circumstances apply to Kapoho given the subsidence, natural topography and existing development. Perhaps the waiver would be acceptable if the shoreline was occasionally flooding but stable. However, the problem of using the waiver in the Kapoho area is that if an area is flooding, it is likely to get worse from ongoing subsidence. It may be possible to resolve this issue by considering the level of flooding and projecting future flooding problems by using a rate of subsidence and the slope of the land. 15 In the 1994 report on Shoreline Certification Review and Recommendations, it was recommended that the shoreline be interpreted in a way that is simple to identify and administrate. Thus increased emphasis on the vegetation line was proposed. Fletcher and Hwang – 1994. 37