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Works ,of Improvement Above u.s. Highway 138, Floodways 1 and :1 have capacity to carry these low stage release flows. However, peak flows from larger storms occurring between the dams and the Highline Canal 'may exceed the canal capacity and overflow the canal banks witho~tentering the,floodways. Simultaneous high $tage principal discharges wi ll,also exceed the High1 ine Canal capacity and ove~- flow the banks. ' No appreciable local flow w.ill entereither floodway above High- way 138 except between Stations 26+00 and 53+00 of Floodway 2. Here, ,local peaks greater than the capacity described above ~ill also overtop the floodway. Below Highway 138 the floodways have' capacity for the flood ,routed 5-year frequency peak storm runoff. Ovid Floodway The Ovid Floodway has a capacity for the 100-year frequency peak storm runoff wi th the project structures in p I ace (850 c. Ls.). S rte~Geol ogy Floodways I and 2 will b~ excavated mostly into older alluvial deposits consisting mainly of firm silty and sandy clays which appear to be stable in the side slopes of existing ditches. In the lower reaches of the floodways" the clays are generally underlain by ,sandy materia,ls at, a depth of five to six feet. Watertable levels in' this area are usually at depths of abput five feet o~ greater. The OVid, Floodway wi 11 be excavated mostly in silndy material at depths of 2.5 to 5'~ 5 feet. ' Stabi lization Floodways 1 and 2 wi II have the designed grade establ ished and ma,in- tained by 27 reinforced concrete drop ,or chute drop spillways with riprap at the lower ends. All existing drops in Floodway I except the recently installed one at Station 28+35 will be replaced. R,iprap will be used along the Ovid F'loodway at bridge, bend and structure locations for stabilization. One grade stabilizing structure will be required for the Ovid Floodway at Station 52+10. 40