2004-07-02 TDJSMLL - Laserfiche WebLink

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FANG:Okay. For this particular flood plain, from my research there was an aerial topo done back in 1979 by the Corps of Engineers and then in the subsequent year the Corps of Engineers did a flood study, thats 1981 it published, and that was adopted as the flood study for this particular Palai Stream. And from there, the stream started way up above Waiakea Uka, and its, you know, in a reserve area. And there is a lot of water now coming through, and in the same region a portion of it is going to Waiakea Stream. So thats why we have a lot of, you know, water drainage coming through into town; and they all join to end up at Waiakea Pond. MOORE:Again, the map, to determine the flood boundaries are based on aerial survey and not on ground survey? FANG:And this aerial survey has accuracy of a five-foot contour, that means with very little or nonground shots. That means that, you know, the accuracy mightbeasgoodasplusorminus2.5feet;andthatshowthefloodplainisanalyzed. Andletmegointohow,theprocessofdevelopinginsidethefloodplain.FEMAdoes allow involvement in the flood plain but they only, the requirement is for floodway, which is the middle, the cross-hatched area. If you put a building in there, they do not allow any rise in the flood, the BFE, which is the Base Flood Elevation. And if you put it outside of the, if you put it outside of the floodway, which is the flood fringe area, you can fill it and you can rise up to one foot. MOORE:Okay, youre talking about two things, a theoretical flood, base flood elevation calculated and, number two, these are the FEMA requirements. FANG:Okay. The County has even stringent requirement than FEMA. It does not allow rise in BFE even in the flood fringe. So, you know, my analysis is to prove that this development will not increase the water to be above the BFE as published by this flood study. And the way I performed my flood study is I did a very detailed topo of the block between Kilauea Aveenue and Iolani Street and Lanikaula and -. MOORE:Excuse me, Yen, for the record, Id like to introduce a map, again, it says Flood Study Map that shows the topographic lines that were used in terms of what Yen did. And it shows the areas that were used by the Army Corps, again, to show you the level of detail that was done in trying to come up with this flood study that he had to submit to the Department of Public Works and FEMA. Again, you cant see it very well. Theres some yellow lines that show the cross-sections that are used by FEMA in determining the width of the flood zone. The magenta/ maroon around, pink lines, are the lines that were surveyed, specifically surveyed for this flood study that Yen used. So its a lot more detailed and a lot more information; and this is ground survey versus aerial survey work. 5