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<br /> <br />could be opened (Figure 67) and the fabric rapidly pulled up on the house and <br />connected to permanently installed snaps (Figure 68). A drainage system was <br />installed at the base of the cutoff barrier (Figure 65) to intercept and drain <br />any underseepage into a sump (Figure 69). It was then pumped outside the pro- <br />tected area (Figure 70). <br />The prototype house was located in Tulsa County, Oklahoma. It was in a <br />Corps of Engineers project area and was subject to removal and salvage. To <br />facilitate testing, the shrubbery and debris were removed from the perimeter. <br />Installation of the system required a trench to be dug beside the footing to a <br />depth of approximately 2 ft. After the digging was completed, the drain sys- <br />tem was installed, as shown in Figure 65. A 4-in. perforated drainpipe was <br />placed at the base behind the protective fabric, and a filter system of rocks <br />was placed over the drainpipe. An adhesive was spread on the house wall at <br />ground level to seal a 2- by 4-in. board to the house. The 2 by 4 was then <br />attached to the house by drilled holes, inserts, and screws. <br />The protective fabric was positioned in the trench and on the house. A <br />1- by 4-in. board was placed against the fabric and attached to the 2 by 4. <br />The storage compartment for the fabric was attached to the 1 by 4. Once the <br />storage compartment had been attached to the fabric and to the house, the <br />backfilling of the trench was begun. The fabric was tightly positioned <br />against the foundation at all times as the backfilling and tamping was accom- <br />plished. The backfill was compacted in 6-in. layers to achieve a density <br />which would minimize the seepage of the floodwaters. Since the test was per- <br />formed about 2 days after compaction of the backfill, the fill did not have <br />time to settle and reduce permeability. It is believed that the early testing <br />of the system caused the seepage to be more severe than would have occurred <br />with a better-compacted backfill. <br />The upper snaps (Figure 68) for attaching the protective fabric to the <br />house at the desired elevation were installed. The top elevation of the pro- <br />tective sheathing should be the depth of flood protection plus 6 in. to 1 ft <br />of freeboard to protect the house from waves caused by boats, wind, etc. (As <br />stated earlier, the maximum depth to which a house or a building should be <br />made resistant to floodwaters is approximately 3 ft.) <br />A backwater valve was installed in the sewage drain line to keep the <br />floodwaters from backing up into the house through the toilet and bathtub. <br />This was accomplished by cutting the 4-in. drain pipe leading from the house <br /> <br />70 <br /> <br />