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10 banks of the normal channel at about 14,000 cfs the entire flood channel is covered with water, except for a few high points on the island. The width of the flood ~hannel is so large that additional flow does not increase the water depth significantly and the boundaries of the flood plain even less so. The 18,000 cfs flood is recommended because it is a reasonable value if Vallecito Reservoir were not able to contain part of the flood peak. This value has been discussed with CWCB staff and they also believe it is the most appropriate flood flow. The attached drawings show the flood water elevations at each of the three cross s.?ctions and along the charonel. The r,arratiVE? below describes the flood wate~' depth for 18,000 cfs. On the north boundary of Lot 1 the flood water level will be at elevation 7325.2 feet which will inundate most of the land in the 1340 foot flood char.,..,el width. The 10l00d level wi 11 bl;? 7318. 1 at the south boundary of Lot 1. The flow will tend to be faster on the west side of the lot because the area is a meadow and there will be IE?SS friction loss as opposed to the island which is densely covered with trees. Generally the flood water depth on the island will be fl'om 2 foot above water to 2 feet below water with the greatest dE?pth or, the east and west bocmdal'ies adjclcent to the stream channels. The center of the isla"d is highet' than the boundaries and the water depth should not inundate the center of the island. The attached drawing entitled "Lot 1 Flood Water Depth" is the channel and flood level profi Ie whi.ch shows the depth of water between the upper and middle cros,; se,ctions. The north and south bounda~'ies of Lot 1 are shown on the drawi r,g so that the flood water depths at various north-south poin1:s on the lot can be determined. The south boundary of Lot 1 is; appl'oxi.mately at the point where the st:ream channel becQrnes steeper which increae;es the v..locity and de,creases the water depth. The gr()und elevat ior, shown on the drawing is the high water line for the small channel Cthe center of the stream channel was inaccesible because of high releases frorn Vallecito Resrvoir); the distances shown on the drawing are along the stream channel and not lot bOtlYidaries. The small channel was selected rather than the main channel because it is the western boundary of Lot 1 and bisects Lots 2, 3 and 4. The flood water depth at Lots 2, 3 and 4 will range from 2 feet lelev 7313.9) at the upstream edge of Lot 2, to 2 feet at the b()undary between Lots 2 and 3 Celev 7306.6) and Lots 3 and 4 Celev 7303), to 5 feet at the downstream edge of the south l()t. The depths shown on the drawing are measured from the high water mark of the stream channel. The water de,pth at the south 101; is deeper because the flood channel constricts from lQl50 feet 1;0 650 feet wi thout an increase in char,r,el slope; therefol'E', the watE.r depth has tel increase. The drawing entitled "Lots 2, 3 and 4 Flood Water Depth" is stream channel and flood profile and shows the flood water depths continuously across the three lots and along the channel. The flow of water will be the fastest aloYlg the stream channel which is through the middle of the three lots. The water velocity will be slowest on the east and west quarter of each lot, this is different than Lot 1 where the slowest velocity was in the middle hal f. In summary, each of the four lots in the proposed subdivision would be inundated during the 100 year flood event. The depth of inundation would as deep as 5 feet depending upon the location in the flood channel. The horizontal boundaries of the flood would