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using Synthetic Aperture Radar Interferometry (“InSAR”) which was conducted by Dr. Ben Brooks and is discussed in detail in this report. This information is found in Chapter 2 and Appendix A of this report. From field observations alone, it is not possible to derive information on subsidence rates, although it is possible to infer that subsidence has occurred in the past. For instance, numerous manmade structures were flooded by the observed high tide event. Currents – Associated with the incoming high tide were tidal currents. The speed of these currents was not measured, as this was outside the scope of the study. Generally, the currents would follow low spots and channels in the rocky lava flows and the roadway as the tide rose. Ripples on the surface indicted the current flow. Generally the deeper the channel, the more force associated with the moving water. Waves – During the August 17, 2005 site visit, it was generally calm and the waves broke offshore over a shallow fringing shoal. Once crossing the shoal area, the combination of shallow water and intermittent lava barriers serve to limit wave action. In addition, wave action is depth limited by the formula (height of a breaking wave = .78 (depth of the water). Many of the inland areas, including the shallow low spots on Waiopae Road that became channels during high tide were inundated by water that was measured in inches, and thus wave action, especially mauka of the road is expected to be negligible, absent a larger increase in water level, perhaps associated with a storm event or future subsidence. Since storm events are not to be included in the shoreline certification process by definition, the high tide line at this section of Kapoho gives a good indication of the upper reach of the wash of the waves. However in later site visits, the important role of wind and wave action and possible increase in water levels associated with setup from these forces was noted as significant. So although the shoreline certification process does not account for storm events, these events play a significant role in hazard risk for the area. Given the low lying areas of Kapoho due to subsidence, future wave action from large and small events would be expected to have an even greater impact in the future. Water Quality - There has been some concern about the water quality of the near shore waters, but no water quality measurements were taken as this was beyond the scope of this report. However, the observation of the incoming water flooding properties with visible cesspools on site indicates that if there is any leaching of the cesspools, this could lead to a direct contribution to some of the tide pools in the Waiopae Marine Life Conservation District. In the Kapoho Reef watch study, leaching form cesspools was identified as the major potential source for enterococci bacteria (Appendix 1). Any new development 18