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Exhibit B February 6, 2007 Steve King, Public Works Director City of Missoula 435 Ryman St. Missoula, MT 59802 RE: Traffic Analysis of Miller Creek Road Improvements Dear Steve: At our meeting on January 24 th you requested that analysis be prepared showing the level-of- service (LOS) for interim buildout and full buildout traffic volumes at the north intersection, under two intersection improvement concepts. The purpose of this letter is to present that analysis for your consideration. Development of Traffic Volumes WGM Group, Inc. (WGM) conducted manual traffic counts to determine the level of existing traffic at the subject intersection in July 2006. The existing peak-hour traffic volumes identified by these counts are illustrated in Figure 1. (All figures are included as enclosures to this letter). WGM then estimated the peak-hour traffic that will be added to the subject intersection by pending development proposals. This process required that the number and type of housing units to be constructed in each development be estimated. Table 1 shows these estimates for each of the remaining undeveloped properties in the Miller Creek traffic drainage. Table 1: Projected Levels of Development Total Units % % Single Family Townhome Maloney 800 60 40 Twitte 660 60 40 Lemm 85 100 0 Hunters Ridge 14 IUU v Boggess & Ginter 320 60 40 Harland & Stanford 290 60 40 ---PAGE BREAK--- King February Page 2 of 4 The Institute of Transportation Engineers (ITE) Trip Generation report (ih Edition) was used to estimate the number of AM and PM peak hour trips that will be generated by each of these ,developments. The results of these calculations are shown in Table 2. Table 2: Development-Generated Trips AM Peak Hour PM Peak Hour Enter Exit Enter Exit Maloney 109 368 382 214 Twitte 91 308 322 181 Lemm 17 52 59 34 Hunters Ridge 5 15 12 7 Subtotal 222 743 775 436 Boggess & Ginter 47 160 171 96 Harland & Stanford 43 147 157 88 Total 312 1,050 1,103 620 WGM then assigned the development-generated peak-hour trips through the north intersection based on the most likely route from each development given the location of the development relative to Upper and Lower Miller Creek Roads. Two assignments were made. The first represents those developments that have reasonable certainty of being approved and constructed in the near term (Maloney, Twitte, Lemm, and Hunters Ridge). These interim buildout development-generated traffic volumes are shown in Figure 2. The second assignment included all of the developments listed in Table 2. This full buildout development-generated traffic volume is shown in Figure 3, which is included as an enclosure with this letter. The interim buildout development-generated traffic was combined with the existing traffic resulting in the interim build traffic volume shown in Figure 4. Similarly, the total buildout development-generated traffic volume was combined with the existing traffic resulting in the total build traffic volume shown in Figure 5. Figure 6 shows a percentage breakout of the traffic volumes projected at the north intersection at full area buildout. Intersection Analysis The interim buildout and full buildout traffic volumes show in Figures 4 and 5 were analyzed to determine the projected delay and LOS at the north intersection. Two intersection configurations were modeled. The first configuration had one left-turn lane eastbound on Lower Miller Creek Road, one through lane northbound on Upper Miller Creek Road, and one through lane southbound on Miller Creek Road, each controlled by a two-phase semi-actuated traffic signal. The southbound right-turn from Miller Creek Road to Lower Miller Creek Road occurs in a separate free-flow lane (approximately 400-feet long) under this configuration. ---PAGE BREAK--- King, February Page 3 of 4 The second configuration differs from the first on the northbound Upper Miller Creek Road approach only. In this configuration the northbound through lane is channelized around the traffic signal and is free flow. The eastbound left and southbound through movements remain under the control of the traffic signal. The capacity analysis results are summarized in Table 3 for intersection configuration 1 and in Table 4 for intersection configuration 2. Table 3: North Intersection Configuration 1 LOS Summary Peak AM Hour Peak PM Hour Interim Build Full Build Interim Build Full Build Traffic Traffic Traffic Traffic Volumes Volumes Volumes Volumes Delay LOS Delay LOS Delay LOS Delay LOS Eastbound Left* 41.8 D 94.3 F 29.8 C 40.3 D Northbound Through 43.6 D 86.7 F 16.3 B 17.7 B Southbound Through 20.3 C 21.0 C 27.3 C 44.6 D Delay is measured in seconds per vehicle. *The existing delay on this intersection movement under today's volumes and stop-sign control is between 34 and 37 seconds during the peak hours. Table 4: North Intersection Configuration 2 LOS Summary Peak AM Hour Peak PM Hour Interim Build Full Build Interim Build Full Build Traffic Traffic Traffic Traffic Volumes Volumes Volumes Volumes Delay LOS Delay LOS Delay LOS Delay LOS Eastbound Left 25.1 C 29.9 C 29.8 C 40.3 0 Southbound Through 24.7 C 30.1 C 27.3 C 44.6 0 Delay is measured in seconds per vehicle. Analysis of the interim build traffic under intersection configuration 1 was previously submitted by WGM to the City of Missoula in relation to this project. That earlier analysis showed iower levels of delay in the AM peak hour due to two primary factors. First, the earlier analysis assumed 12-foot wide lanes, whereas the current analysis reflects the 11-foot lanes currently being designed. This change results in delay increases of 3.5 to 5.5 seconds in the AM interim build configuration 1 analysis. Second, the earlier analysis assumed a maximum of 3% approach grades, whereas the current analysis reflects the five to six percent approach grades ---PAGE BREAK--- that will be included in the final design. This change results in increased delay of 2 seconds on the eastbound approach. We look forward to discussing this traffic analysis with you during our meeting scheduled with the City of Missoula Public Works Department on February 8th. , Sincerely,uZ/ Mark Bancale, P.E. Senior Traffic Engineer Enclosures cc: Kevin Siovarp Greg Robertson Gilbert Larson W:\Projects\070420\Docs\Trans\020607King.doc ---PAGE BREAK--- I 'North Legend AM(PM) Figure 1: 2006 Existing Traffic Volume Miller Creek Road Lower Miller Creek Road Upper Miller Creek Road ---PAGE BREAK--- Miller Greek Road I North Legend AM(PM) Lower Miller Creek Road Upper iMiHer Creek Road ---PAGE BREAK--- Figure 3: Total Bulldout Development-Generated Traffic Volume :M:iller 'Greek Road North Legend AM(PM) Lower Miller Creek Road Upper iMiller Greek Road ---PAGE BREAK--- Figure 4: Interim Build Traffic Volume Miller Greek Road 1 ! North Legend AM(PM) Lower iMi'ller Creek Road Upper :MU1er Creek Road "These 'movements will not be accommodated underthe improved intersection design. Aroundabout et Briggs Street Is one possibil:ity for accommodating these minor traffic volumes. ---PAGE BREAK--- Figure 5: Total Build Traffic Volume .MHler Creek Road I North Legend A:M(IPM) Lower MiUer Creek Road Upper·M'iller Creek Road not be accommodated under the improved !r'filtersection design. A roundabout at Briggs Street is one possibility for accomrnodating these minor traffic volumes. ---PAGE BREAK--- Figure 6: Source of Traffic at North nyn at Full Area Bullclout .AM Peak EExisting Peak Hour Traffic Gount ·ffiI.Maloney Twitte Lemrn Hunters