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•o <br />M <br />• <br />i the BPP). Structure vulnerability of oceanfront "developed" parcels is considered <br />a function of length of the seawall or revetment, mean high water line, annual <br />erosion rates, and anticipated storm recession for a 15 -year design storm. The <br />average annual erosion rates over the past 11 years were computed along the <br />project sectors, based on the period of 1986 to 1997. Figures 2 and 3 provide <br />general location maps and typical photographs depicting the characteristics of <br />properties that front the proposed beach restoration projects and Table 1 <br />summarizes the sand volumes recommended for each project area. <br />2.2 CALCULATION OF STORM PROTECTION BENEFITS <br />The storm protection benefit received by an individual property, within an <br />identified project area, is the expected reduction in land loss due to erosion and <br />the associated cost of the land protected and the cost to build an erosion control <br />structure for storm protection or the costs of maintaining or repairing an existing <br />erosion control structure in the absence of the project. In the case of oceanfront <br />homes, and properties with upland improvements such as pools and cabanas, <br />which are not presently protected by a hardened structure (such as a seawall or <br />revetment) the distance from the mean high water line to the most seaward <br />structure was compared with the expected erosion rates over the next 8 years <br />and the storm recession distance for a 15 year return period storm event, except <br />for Sector 7 where the storm recession distance for a five (5) -year return period <br />storm event and eight (8) years of erosion were applied. <br />The expected land loss value consists of the discounted stream of future losses <br />over a 30 -year period. The extent of loss varies by sector of shoreline according <br />to the erosion rates. These losses also consider land valuers haaeh vjirlfha -i <br />distances between buildings and the mean high water line, The dune erosion <br />model EDUNE was evaluated at four (4) beach profile locations on the Island <br />98 W"82REPORTIORAFT106019WAE <br />6 <br />