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III. Future Conditions The CSAH 14/I-35E interchange reconstruction project involves reconstructing the interchange to modify the existing grade-separate diamond interchange to a grade-separated folded diamond type "b/a" interchange, as recommended in the I-35E/CSAH 14 Interchange Alternatives Evaluation memorandum (SRF Consulting Group, Inc., September 2005). The memorandum details the exhaustive analysis conducted to select the preferred interchange concept. Following the selection of the interchange concept, a preliminary analysis was conducted and documented in the 1-35E1CSAH 14 Interchange Corsim Analysis memorandum (SRF Consulting Group, Inc., October 2006). As a part of the interchange reconstruction, CSAH 14 improvements have been proposed. CSAH 14 improvements include widening CSAH 14 to a four-lane divided roadway to tie into the existing four-lane divided roadway sections east and west of the interchange. The northbound 21" Avenue approach to CSAH 14 is proposed to be realigned to form the south leg of an intersection formed by the 1-35E southbound exit ramp. A MnlDOT Level 1 layout has been prepared (SRF Consulting Group, Inc., May 2008) to illustrate the improvements associated with the interchange reconstruction (see Figure 2). Following the improvements, the posted speed limit along CSAH 14 will be 45 miles per hour through the interchange and, as previously noted, traffic signal control has been recommended at the reconstructed CSAH 14/1-35E ramp intersections and the reconstructed CSAH 14/21'1 A venue intersection. Based on the Anoka County interchangelroundabout/intersection decision process developed for planning purposes, roundabout control shall not be considered feasible at locations where the ADT exceeds 20,000. For existing year 2008 volumes, roundabout control could be feasible at the CSAH 14/I-35E Southbound ramps and the CSAH 14/21'1 Avenue intersections; however, roundabout control would not be feasible under year 2030 forecasted volume conditions. IV. Traffic Volumes Existing Year 2008 Volumes Existing year 2008 turning movement volumes and approach volumes were collected (SRF Consulting Group, Inc., July 2008) at the two CSAH 14/I-35E ramp intersections and the CSAH 14/21" Avenue intersection. For existing year 2008 turning movement volumes, see Figure 3. Existing year 2008 approach volumes can be found in Appendix A. Year 2030 Forecasted Volumes Year 2030 volume forecasts were developed for the aforementioned preliminary analysis of the interchange reconstruction project. The forecasting was based on the I-35E Corridor Final Alternative Urban Areawide Review (Dahlgren, Shardlow & Uban, Inc., et aI., September 2005) and took into consideration future roadway improvements and planned adjacent developments. Details of the forecasting methodology are documented in the CSAH I4/I-35E Interchange Forecasts Assumptions (SRF Consulting Group, Inc., June 2006). For year 2030 tuming movement volume forecasts, see Figure 4. ~CONSUl..TINC Gaour, INC -4- January 30, 2009 21