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existing gabion wall, a distance of about, 4000 fee}.. The proposed levee would be approximately 5 to 7 feet high for 100-year protection with the ,.....------.....,.- ,ecommended freeboard. Flooding in this area '~ould inundate (jnly an auto, salvage ,)I~rd, however, once flows break out of the channel, the water cannot get back to the channel and consequently floods the "Riverside" area (Area B). The existing gabion wall adjacent to the "Riverside" area is high enough to confine the flows to the main channel. Construction of a permanent levee along the north bank would increase the 100-year water surface elevation les~_than 0.5 feet throughout this location. ,r Estimated Project Cost: $291,000 "/3,. r (' Improvement #3 - A p"rmanent levee is recommended a'long the J}QrJh_ub..(l.n,~ of the Colorado River from the Denver and Rio Grand Western Railroad Bridge approximatelY~OOO '~et upstream to the existing bluffs at Area A. The levee would be .2.J.Q~.'~feet high in order to maintain 3 feet of freeboard above the 100-year water surface elevation. Construction of the levee would completely eliminate Area A from flooding and would also confine the entire floodplain within the river channel. The bridge downstream and the bluffs upstream provide tie pOints for the proposed levee. '.1' '\ ~ Estimated Project Cost: $300,OOO,/~ ! Improvement #4 - A ~ermanent levee is recommended along the north side of the river just downst.ream of the Grand Avenue bridge. This levee would be approximately~t long and.,4_ t2 6 t?~,t high to meet the suggested levee criteria. This improvement would protect the cities' maintenance buildings during a large flood event. Slope protect'ion for this area is imperative because of higher vel Jcity flows through the bridge. / t > Estimated Project Cost: $ 60,000/' { t 'II. Improvements #1 through #4 are based on permanent measures to help alleviate the flooding hazard. Any of the permanent levee systems can be constructed to protect against a lesser flood event, or even be constructed for temporary protection. The flood profiles on Sheet 1 can be used as a guide in determining the height of temporary levees. An additional temporary or permanent improvement could be substituted for improvement #2. This improvement could be made along the north bank of the ri ver to he lp protect the "'R i vers i de" area from flooding. A berm approximately 3 to 5 feet hiCJh, constructed along the east side of Hale Avenue, would prevent overbank flooding from reaching the "Riverside'" area. The be)'m would direct any overbank flows back into the main channel. This improvemen: would help protect the "Riverside" area but would not 9