Item 8A, Update on Interstate 694, Hwy 10, and CR 96

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Evaluation of Phasing Options for Highway 10 May 20, 2008 Page 3 In order to conduct the analysis, the interchange type, size and location along Highway 10 was based on the April 9, 2008 interchange concept plan (Alternative I) that was analyzed in the previous memorandum that discussed Highway 10 alignments. The interchange location shown on phasing figures represents the furthest north location the interchange can be built to still work with the ramp design for 1-35W_ To develop the traffic forecasts the following modeling assumptions were used: I. The existing (2005) Twin Cities Regional Model was used as the base. 2, The design year that was modeled is 2012 to coincide with the completion of the Highway 10/ County 96 grade separation along with the initial opening of development on TCAAP_ 3. Background traffic was increased to the year 2012. 4. TCAAP traffic was projected based on an initial development phasing plan provided by Ryan Companies. 5. The existing roadway network was used to distribute the traffic with the following modifications: . Completion of the 1-694/1-35E "Unweave the Weave" project (proposed completion 2008). . Completion of the full access CR H/I-35W interchange (proposed completion 2011). . Completion of Rice Creek Parkway between CR I-I and CR 96 (proposed completion 2010). . Completion of the Highway 10/ County 96 grade separation (proposed completion 2012). 6. The traffic operational modeling was perfonned for four alternatives to detennine the effect of losing the southbound exit ramp: 3. Current Conditions - No Highway 10 grade separation or local access interchange b, 2012 - Highway 10 grade separation and local access interchange without southbound exit and no west frontage road c. 2012 - Highway 10 grade separation and full local access interchange with no west frontage road d. 2012 - Highway 10 grade separation and full local access interchange with west frontage road Synchro Analysis Synchro traffic modeling software was used to perform traffic operational analysis. The capacity analysis results are indicated by Level of Sevice (LOS) based on a comparison of model delays against delay thresholds defined in the Highway Capacity Manual (HCM). LOS indicates how well an intersection is operating. Intersections are given a ranking from LOS A through LOS F. LOS A indicates the best traffic operation and LOS F indicates the worst. LOS A-D is generally considered acceptable by Ramsey County and MnJDOT and is used as the threshold for this analysis. The detailed results of this analysis are shown in the tables attached to this memorandum. Findings Due to background growth in traffic, the additional traffic projected from TCAAP, and with the traffic changes associated with grade separating County 96/Highway 10, a number of intersection deficiencies were revealed. The following intersections will have operational problems that require signalization in 2012 to achieve acceptable LOS under any scenario: . County 96/0Id Highway 8 . County 96/1-35W west ramp . County 96/1-35W east ramp . County 96/OId Highway 10