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However, this can be difficult to do since the rate of subsidence in this report is based on three years of data and ideally the area should continue to be monitored. Also, -4 while there is a general regional slope of 3.5 X 10 degrees, there is much variation from lot to lot. So while attempting to plan for ongoing subsidence events is theoretically possible to do, it is difficult to do in practice and episodic events such as a large earthquake, hurricane, tsunami or subsidence event further complicate this option. When the Hawaii County Planning Department was conducting observations for certain applications to determine surface connection, the State Surveyor, Reid Siarot, indicated that their Department may be open to a waiver of the shoreline certification process for those lands mauka of Waiopae Road. Now that ongoing subsidence has been indicated, and the DLNR is taking the lead again in shoreline 16 determinations, it remains to be seen if this is an option they would entertain. 3.5 Conclusion and Recommendations The shoreline recommendations and options discussed in this section may be viable, but it is the final say of the State Surveyor to determine the manner by which shorelines will be certified. The State Surveyor’s office will examine each certification on a case by case basis. So, although the proposals in this report appear sound, a check should be made at the applicable agencies (DLNR, County of Hawaii Planning Department and Army Corps of Engineers). The option to exclude gravity flow in determination of the shoreline would affect primarily a few houses immediately mauka of Waiopae Road. If gravity flow were excluded, development pressure will likely increase for a few areas. This has pluses and minuses. On one hand, the investment that landowners have placed in the property can be partly recovered. Interviews with some landowners have indicated that their main concern is whether they can build on some of the vacant lots in this area. On the other hand, the area is subject to flooding, tsunamis and hurricanes and therefore, some of the areas are at high risk from natural disasters. Ongoing subsidence will increase this risk. Thus hazard mitigation and disaster risk reduction will need to be addressed in a more robust manner. This is covered in subsequent sections of this report. Of course each lot will have to be examined on a case by case basis, and rough generalizations are applied. For many of the lots makai of Waiopae Road, the clarification of the shoreline to exclude gravity flow should not affect these lots greatly. There will still be an issue of flooding of these lots, and whether they can be built on. However, it should be noted that the lots makai of Waiopae Road, but towards Kaheka 16 Also by interview with the Army Corps of Engineers, the Corps is unlikely to claim an open water connection for the channels crossing Waiopae Road (Figure 2-7), although they will treat tidal ponds makai of the road as wetlands. 38