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"I "I I I I I I I I I I I I I I I I Another alternative for stabilizing the slope is a cribwall. The wall could be built with one lift ranging in height from 10 to 30 feet or it could be terraced with 2 or 3 lifts. There are several types of cribwalls including welded wire, cast in place concrete, and reinforced soil embankment. The pri ce of these wa 11 s coul d range from $320,000 for we 1 ded wi re to $540,000 for reinforced soil embankment. Terracing the wall would increase the cost slightly but would also create landscape buffers between each terrace to enhance the wall visually. Approximately 0.6 acres of dev.elopable land woul d be lost to a terraced wa 11. On the other hand, a wa 11 with a s i ngl e lift would create approximately 0.6 acres of developable land with a restricted .use. The.se types of walls require ties extending back into the earth for a distance of roughly 1.2 times the wall height. Therefore the area just behind these walls would be restricted to such types of use as parking lots or driveways. V. flOODPLAIN REClAMATION A HEC-2 analysis was conducted to evaluate the impact on the water surface elevation of placing fill material in the flood fringe area on the west side of the creek near U.S. Highway 85. Figure 4 shows the location of this area. Flooding in this area is caused by backwater from the bridge at U.S. Hi ghway 85. Thi s a rea of the fl oodpl a i n is not used for conveyance of the 100-year storm and fill placed in the area shown would not increase the computed water surface elevations. Copies of the HEC-2 runs with proposed encroachment are in the Appendix. It is recommended that the placing of fill in a Flood Fringe area should result in ground elevations at least one foot higher than the rOO-year flood elevation in the adjacent stream channel. According to the Soils Report, fill in this area should be non swelling sands placed in thin lifts at or above optimum moisture content and compacted to high densities.