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I I I I I I I I I I I I I I I I I I I 6TH STREET TO 9TH STREET A buried concrete slope apron would be provided at the 6th Street bridge to act as a grade control structure and to locally increase the stream- bed slope through the bridge constriction. The proposed floodwall and berm to the north of Boulder Creek would prevent the diversion of floodwaters associated with the lOO-year discharge of 12,000 c.f.s. onto Canyon Boulevard. The existing kid's fishing pond would be excavated and enlarged to provide increased flood conveyance. The existing inlet and outlet structures on the west and east ends of the kid's fishing pond would be removed and replaced in conjunction with the proposed pond enlargement. Access to the south bank of the kid's fishing pond and the north bank of Boulder Creek would be provided in conjunction with the proposed inlet and outlet works. 9TH STREET TO BROADWAY A buried concrete apron would be provided at the 9th Street crossing to act as a positive grade control structure and to locally increase the stream bed slope through the bridge constriction. The main channel would be enlarged and excavated to provide increased flood conveyance. The reach between the 9th Street bridge and the Boulder Public Library would be excavated and widened to provide increased flood conveyance and improved flow transitions. A retaining wall having a total length of 175 feet would extend east from the south abutment of the existing 9th Street bridge in conjunction with the proposed excavation. The area to the north of Boulder Creek between 9th Street and the Boulder Public Library would be bermed to prevent the diversion of floodwaters asso- ciated with the estimated lOO-year discharge of l2,000 c.f.s. The Justice Center parking lot to the southeast of the intersection of 6th Street and Canyon Boulevard would not be modified. An aesthetically pleasing, simulated rock floodwall having a maximum height of four feet would be built to the immediate south of Canyon Boulevard between stations l296+00 and 1292+00. The proposed floodwall would tie into a proposed berm on the southwest corner of the inter- section of Canyon Boulevard and 9th Street. The two columns supporting the library bridge south of the main library would be removed and the immediate area excavated. The remaining columns and bridge superstructure would be reinforced in conjunction with the removal of these columns. The area to the south of the Childrens Library would be excavated to provide increased flood conveyance. A retaining wall having a total length of l80 feet would be installed 35 feet to the south of the Childrens Library. An existing garage to the 5