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dive::.-t high flows to the existing basE fJ 01,..' c:hannel invert. The esti- mated IOO-year flood plain just downstre<'IJTI .)f 96th Avenue due to diking is shown in dashed line on the drawing. In this reach the Burlington Northe,-n H.aiL[oad crosses the First Creek at Stat.on 218+80, Highway 2 at Slatlon 220+20, Peoria Street at Stat:Lon 2l8+3() and 96th Avenue at. StatioTI 2'~O+9(). Burlington Northern Rail,~oad crosses the creek over a bridge h~'ling five spans three of which have 13_5' clear span and two of 12.5' clear span. The 100-year flow in the F.rst Creek will pass under the railroad bridgE' and hence no modification is suggested for this bt:idge. Both Peoria Street and 96th Avenue crossings will have no aded LiOJld 1 st ruc1:ural improvements. The lOO-year flood will overtop t_hese tv/Cl roads < For Highway 2 a new brid:,e has been proposed. FLood PlaiCe ;;on Illg j,; recommended for the euti ce reach. Hig~~_~~ Highway 2 at present has two SL)-ll diameter eMP openings under the :.-oadway. It is proposed to provi,de ~l rll~W bl:idge for Highway 2 in ordec to pass the 100-year flow wi t.ho"_t "vertopping the bridge. The exis~:ing invert elevation cannot be ],owct"ed as 1_his will a:ffect the flow through the existing railroad bridge wllich lS 11,0 feet downstream. In orde:~ to pass the IOO-year flow withot;,t c,ve,rtopping it is proposed t.o raise the existing top of roadway by 2.0' over a length of 1,600 feet and provide a bridge with three spans, (~EICh of ;:3.0'. The height cf the open:lng will be 8.0'. The First Creel< \.,ill be chanIle Lized on the up.' stream side for a length of 500 feet to minlmize ponding. The telephone cabl4~ crossing the flood plain at this l,elca-~ion has to be relocated, The reach between 96th Avenue clOd Buckley Road lies in the Rock:r MountaiIl Arsenal area. This area ~1a~ not :incorporated in the pre- sent flood plain studies. [1I-7