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that does not protect the wastewater from flood inundation will likely contribute to offshore water quality degradation. Wastewater issues are the subject of additional studies as noted in Section 4.2.2. The main observations for the August 17, 2005 site visit had to do with the tides. Observations were made at the site from 9:30 am – when the water was at a low point, until well past when the high tide peaked. The extent of inundation by the high tide for that day was mapped using two satellite GPS units provided by Dr. Ben Brooks. These units are dual frequency receivers that operate in a kinematic mode. The accuracy of the units are measured in centimeters, versus ten meters for the units commonly found in commercial stores. The team set up on site at 9:30 am and did an initial reconnaissance of the study area. Six observation points were set up and communications to the team members were established. The tide steadily rose, and the water crept through channels in the fields of lava and began to breach Waiopae Road (Figure 3-1). The progression of flooding for this high tide event is shown on Figures 3-2 to 3-4. There are numerous low spots in the road. This may have been due to initial construction, but appears that the tidal currents passing over the road repeatedly served to cause erosion and make any low spots deeper than they originally may have been. Once the water crossed the road, it spilled over to low areas on the mauka side that are significantly below the road itself and this caused significant flooding (Figure 3-4). The flow of water to these mauka areas is more gravity flow of water than wave action as the limited depth of water over the road limits the wave action inland of the road. 19