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IV. BRIDGE ALTERNATE EVALUAnON In the early stages ot the North Metro Travel atudy, twelve bridges were selected tor analya1s. Three ot these were existing structures, one was under construction, and eight were proposed candidates ot new right-ot-way at various locations in the study area. Consequently one of the fint tasks ot the Technical ColJllD1ttee was to reduce the number ot possible Dew bridges trom eight to a few choice candidates. The North Metro Travel Task Force Technical Committee ran through tour separate bridge scoring exercises. The scoring used criteria (see Criteria Scoring Sheet) that considered both environmental and system concems. The 1-6911 bridge was not included in this exercise, for Mn/DOT is currentlY scheduled to imProve the facility. Consequently only eleven bridges were included in the scoring. In each instance the eleven r1.ver bridge alternatives were ranked on the basis ot total points tallied trom the criteria sheets. The tinal scor1.ng exercise included two Bypass alternatives, one upstream and one downstream trom the existing TH 169 / Ferry Street Bridge. Interesting enough, the single highest rated and two lowest rated bridge candidates remained constant in their respective standings under each scoring exercise. Other bridges were tairly consistent in their scoring while others were variable. Although some recollllll9ndations could be made from the results thus tar, the Colllll1ttee decided instead to prioritize three corridor segments. The ColJllD1ttee began the criteria ranking process intendiJIg to recolllllend two or three bridges tor continued additional study. During their deliberations they began to see the issues in terDlll ot river corridor segments rather than in terms ot individual bridges. The Committee also spent time discussing strategies to deal with the central issue and concluded that both long-term and short-term strategies will be needed. With regard to river corridor segments, i1; was concluded that the river from Bridge No 2 (CR 121 _ Armstrong Bl) down to Bridge No.1 (Noble Av - Crooked Lake Bl) was a priority corridor. In this corridor is found the lowest ranked alternate (TH 169) and II of the 5 highest ranked alternates (Bridges 2,3,5 & 6). From this the ColJllD1ttee recolllllended that additional studY should focus on long and short term strategies in this corridor. The second priority corridor is on the river from Bridge No.8 (109th Av - Hanson Blvd) to Bridge No. 11 (13rd Av _ Mississippi st). In the second priority corridor, traff1.c demand and bridge V/C rat1.os did not change significantly among all the altemates. Improvements to 1-6911 are programmed, and TH 610, as planned, has capacity on the bridge. The third priority segment is ident1tied as solely TH 101. The long term prospect is to improve TH 101 and add a parallel bridge. There is little reason to consider an altemate alignment. This leaves several major issues to a more detailed alternatives analys1.s. TH 169 is a state as well as regional facility. When modeled as a local bridge with a nearby bypass, the TH 169 bridge and Ferry Street still attracted the majority ot traffiC. In the short term, traffic would flow better w1.th spot improvements on the approach routes, at signals and on system connections to other state highways. In the long term, the issue remainS where to run a state/metro facility _ on an existing alignment or on a bypass? '27 44 ~