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I I. I I I I I I I .. I I I I I I .. I I author believes that the methodology in this study should not be used without modification. The TVA in 1970, developed residential structure and contents depth-damage (per room) tables. Tables were developed for four differ- ent velocity ranges; Ofps, 1-7 fps, 8-14 fps, and over 14 fps. For masonry one and two-story structures and also for two story frame struc- tures, the tables are identical, They are only different for one-story frame structures. It is difficult for the author to understand how, for example, 19 feet of water in a two-story frame structure with flood waters moving at velocities greater than 14 fps does no more damage than the same depth of water with no velocity. The TVA is no longer using these curves. In a letter to the author from the Center for Economic Studies {U.S.A,C.E., 1974) the Corps stated that velocity effects are implicitly included in each flood damage study. Thus, the depth-damage curves being used by the different Corps Districts may take the average velocity within the District into account. More generally, however, the depth-damage curves being used by the different Districts were developed after a damage survey in one particular area within the region and the velocities prevalent in that area may not be representative of the rest of the District. In a letter from James (1974), he referred to the Chief of Engineers, "Flood Proofing Regulations" in which they recommend that velocity be re- 2 lated to an incremental additional depth of aV /2g where a is a suitable coefficient of drag for the building shape and no less than 1.25, While the depth-damage curves published by the FIA are based upon national averages, a 50% surcharge is imposed upon actuarial insurance rates in "coastal high hazard" areas, These are areas in which wave action 21