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X-5 that a ra Ised foot path be constnJcted throOl,gh ei.ch bridge. The raised bench for the area above the low flol~ channel ilMledlately downstream of the bridge wi I I also act as a flow spreader and energy dlsslpator. 33. The area between North Wash I ngton Stroaet and 136lth Avenue I s the on I y location within the bas In where a o:ontinuous geometric grass-lined channel Is to be constructed. Street overtClppln9 and critical eleva- tion requirements for the German [)Itch head9ilte combine to make a des I gn In th I s area very cr I t I ca I. To meet olfertopp I ng cr I ter I a and to maintain existing German Ditch facilities without major cost, It Is necessary to: (Sheet 10). a. Build a new bridge 190 feet wide on North Washington. b. Construct a geometric channel with a capacity of 1300 cfs before overtopping and provide a 250 cfs low flow channel within the geometric channel. c. Retain the existing German Ditch headgat~' and bridge. d. ReJoco.te the German Ditch headgat" on th~, east bank of the geo- metric channel and use the old BI9 Dry Creek al ignment to carry the G,arman Ditch flows to the exis,tlng headg8te near North Wash Ington Street. e. Replace the newly constructed 136th AvenlJe bridge or add to the brldgl! sufficiently to obtain the 'squivalent of a lSD-foot wIde new brl dge. f. Constl'uct a low berm to protect existIng buildings near North Wash ington Street. 34. Minimal Improvements are necessary to protect the Westminster Sewage Treatment Plant after HurOn Street Is raised and a new bridge is COns tructE!d. (Sheet 11). 35. Allow the Bull Canal to continue diversions as thEy are presently doing and constr'uct a V-shaped swale from the' over'flow to the existing Big Dry Creek thalweg. It does not seem cldvlsable for Westminster and the Urban Drainage and Flood Contml Dlstricl: to tamper with the existing conditions because If adj'Jstme'nts ar'e made to the Bull Canal diversion the governmental entities may be n,sponslble for the main- tenance of embankments and repairs for flood dama!~e. (Sheet 12). 36. The Broomf Ie I d Sewage Treatment P I'mt I s not I nundated and requ I res no Improvements for protection. (Sheets 13 ""d 14).