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HomeMy WebLinkAbout16 - Traffic Impact Study - South University District Lot 1, Ph 2 TRAFFIC IMPACT STUDY for SOUTH UNIVERSITY DISTRICT LOT 1 - PHASE 2 1 y DEVELOPMENT Bozeman, Montana Prepared for STAHLY ENGINEERING r J v Prepared by r MARVIN & ASSOCIATES 1300 North Transtech Way Billings, MT 59102 6 V • , 1, t' October 25, 2016 !� i TRAFFIC IMPACT STUDY for SOUTH UNIVERSITY DISTRICT LOT 1 - PHASE 2 DEVELOPMENT Bozeman, Montana Prepared for STAHLY ENGINEERING Prepared by \11111111lrl, T MARVIN & ASSOCIATESA•�� '': 1300 North Transtech Way * ROBERT R. Billings, MT 59102 = MARVIN o 3697E ;W "'V ' ,, Or1IAL 1 ` •• //�f✓� !lIIIIIIl1111 f r October 25, 2016 P.T.O.E. # 259 TABLE OF CONTENTS PAGE INTRODUCTION 1 PROPOSED SITE DEVELOPMENT 1 EXISTING CONDITIONS 3 Streets & Intersections 3 Existing Traffic Volumes 4 Existing Capacity 6 DEVELOPMENT TRAFFIC PROJECTIONS 7 Trip Generations 7 Trip Distribution 10 Traffic Assignment 11 TRAFFIC IMPACTS 13 Existing Plus Development Traffic Volumes 14 Capacity 16 Future Traffic 18 Future Conditions Plus Site Traffic 20 Future Capacity 20 MITIGATING MEASURES 23 Year 2021 Traffic Projections 23 Mitigation Concepts 25 CONCLUSIONS & RECCOMMENDATIONS 26 APPENDIX A—TRAFFIC VOLUMES APPENDIX B—CAPACITY CALCULATIONS LIST OF TABLES PAGE Table 1. Existing Peak Hour Capacity Analysis Summary 6 Table 2. Auto & Bike Access Traffic—Stadium View Apartments 8 Table 3. South University District Phase 2 Development Trip Generation 10 Table 4. Existing Plus Site Traffic Capacity Analysis Summary 17 Table 5. Future Year 2031 Conditions Capacity Analysis Summary 22 Table 6. Future Year 2021 Conditions with Interim Improvements Capacity Analysis Summary 26 LIST OF FIGURES PAGE Figure 1. SUD Phase 2 Development Site Location 2 Figure 2. Existing Traffic Volumes—2016 Counts 5 Figure 3. Trip Distribution Percentages 11 Figure 4. Site Traffic Volume Assignment—2016 Conditions 12 Figure 5. Site Traffic Volume Assignment—Future Conditions 13 Figure 6. Existing (2016) Plus Site Traffic Volumes 15 Figure 7 Traffic Volume Projections—Year 2031 Conditions without Site Traffic 19 Figure 8. Traffic Volume Projections—Year 2031 Conditions with Site Traffic 21 Figure 9. Year 2021 Traffic Projections with Site Traffic Volumes 24 AAMI r� Marvin &Associates South University District Lot 1, Phase 2 Development TIS MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 INTRODUCTION The following narratives serve as a summary report of operational impacts that could be associated with the proposed Phase 2 development of the South University District, herein referenced as the SUD Phase 2 development. The narrative figures and appendix encompass all intersections that would potentially be impacted by Phase 2 development, including all intersections between arterial and collector streets within a 0.5-mile radius of the development. PROPOSED SITE DEVELOPMENT The proposed development property is located south of Kagy Boulevard with the northern boundary parallel to Campus Boulevard; the eastern boundary located along S 11 th Avenue; the southern boundary along undeveloped property; and the western boundary along S 141h Avenue, as shown in Figure 1. Phase 2, Lot 1 is within a large tract of land known as the South University District, which is located South of 19th Avenue and south of Kagy Boulevard. The development will be known as the Bozeman Lofts and Townhomes ("Lofts") and will be built on a 16.05-acre parcel. The apartments will contain 887 bedrooms in 268 apartment units. The apartments will be nearly identical to those contained in SUD Phase 1, which is located south of Phase 2. In addition to the apartment complex, there would be approximately 3,550 square feet of retail space containing complimentary commercial businesses. This Traffic Impact Study (TIS) addresses potential impacts associated with full development of both residential and commercial land uses within the Phase 2 property boundary. Access to the property will initially be served by S. 11th Avenue. In future SUD development phases, Campus Boulevard will be extended to S 19th Avenue where Campus Boulevard will become the fourth leg of an existing intersection with Stucky Road. In addition, planning and design of an extension of S 11th Avenue to Graf Street is currently underway and an extension of Graf Street from S 3rd Avenue is currently under construction. SUD Phase 2 Development Traffic Impact Study Page 1 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 R. VI ilk ,�:�o -ter �. art ,: .`+• � -. `;.,��� „ #1*7 y ♦ 5. r Ar 7' r V Un'IVY d�l� n- • i e - CL A4V writs wC CL 41 $.,--r-�1 ;1L6:M Ck d �� . . z C SUD Phase 2 Development Traffic Impact Study Page 2 MGM MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 The aforementioned projects will provide alternative connections for the SUD Phase 2 property development. This TIS addresses potential impacts to the adjacent street system based upon the initial access conditions and future conditions (year 2031) that would be associated with new street system facilities. EXISTING CONDITIONS Streets & Intersections Potentially impacted intersections located within 0.5-miles of the proposed development site are Kagy Boulevard intersections with S. 11 th Avenue, and S. 7th Avenue. The planned intersections of S. 19th Avenue and Stucky Road, and Graf Street and S 11th Avenue would also have potential for impacts by the year 2031. Kagy Boulevard is currently a two lane street with left-turn lanes at its intersection with S 11th Avenue and bike lanes east of S14th Avenue. Kagy Boulevard extends from a termini point just west of S. 19th Avenue, past the MSU campus, to rural areas east of Bozeman. Montana Department of Transportation (MDT) is currently in the process of designing extensive improvements to Kagy Boulevard between S 19th Avenue and S 3rd Avenue. Preliminary design activity has resulted in a future street section with 5 lanes, including a continuous two-way left-turn lane. Bike paths are included along its length and pedestrian tunnel/s are under consideration to provide safe pedestrian crossings of Kagy Boulevard. South 11 th Avenue extends from a point south of Campus Boulevard north, thru the MSU campus, to an intersection with Main Street. It currently operates with one lane for each direction of travel and includes bikes lanes on either side. At its intersection with Kagy Boulevard it accommodates separate left-turn lanes on all four legs of the intersection. SUD Phase 2 Development Traffic Impact Study Page 3 MF MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 South 7th Avenue extends from a point south of Kagy Boulevard to West Grant Street, approximately 0.35 miles north of Kagy. South 7th Avenue has served as a secondary access to surface parking lots, south of the MSU Student Union Building. At the present time, building projects (including a new parking structure) has removed the parking, which is being accommodated by the stadium parking lot in the southeast corner of Kagy Boulevard and S 11 th Avenue. The northbound approach to this intersection serves to access corporate offices with a finite demand in the am, pm, and noon hours. The southbound approach has a separate right-turn lane and a thru/left-turn lane, while the northbound approach has a single lane approach. A marked pedestrian crossing of Kagy Boulevard exists on the west side of the intersection. Existing Traffic Volumes Electronic traffic counters were used to count traffic on South 11th Avenue, south of Kagy Boulevard and on Kagy Boulevard, west of S 11th Avenue. Additional electronic counters were placed on Campus Boulevard and the main access to Stadium View Apartments (SUD Phase 1). In addition, electronic counts taken in 2015 on Arianna Way were used to document total vehicular traffic accessing the existing apartment units. Peak am and pm traffic counts were taken both manually and with Mio-vision cameras (provided by Sanderson Stewart) in 2016. Hourly traffic volume summaries from those counts can be found in Appendix A of this report. The results of these counts are illustrated in Figure 2. Also shown in Figure 2, are the Average Weekday Traffic (AWT) volumes. In comparing these counts to the SUD Phase 1 study in 2011, it was discovered that there was only modest traffic growth on Kagy Boulevard while more substantial growth occurred on S 11 th Avenue, both north and south of Kagy Boulevard. SUD Phase 2 Development Traffic Impact Study Page 4 / �._r, MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 CC '?it ••; 40 �o 0 x V dill/ wzl T 00ea .�. 026 —asli' ' wWll � oM r � 46MOW al m SUD Phase 2 Development Traffic Impact Study Page 5 1[:-\- MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 It should be noted that the peak am hour of traffic on the arterial streets occurs between 7:30 and 8:30 while there is no definitive peak am hour at local street intersections. Peak pm hour traffic at the arterial intersections occurs between 4:45 and 5:45 pm. The peak hour of traffic for the Stadium View Apartments occurs between 7:00 and 8:00 pm with approximately 37% of the total average weekday traffic (AWT) occurring after 6:00 pm. Existing Capacity Capacity calculations were completed for the study intersections based on existing geometry and traffic volume counts. Table 1 provides a summary of the calculation results and the calculations can be found in Appendix B of this report. Table 1. Existing Peak Hour Capacity Analysis Summary Intersection M(1E EB YM NB SB intersection Movement Group L TR L TR L TR L TR OVERALL Control Delay(slveh) 10.7 83 14-2 293 25.9 26.6 286 27.3 191 KagyBoulevard&S.111h LOS B A B C C C c c B Avenue Peak AMHour VIC Ratio 0,31 0.54 0.09 0,81 005 016 044 0.28 0.63 Queue Length(95%) 8 9 2 14 2 2 3 4 Movement Group L TR L TR L TR L TR OVERALL Control Delay(s/veh) 140 101 12.5 299 25.7 24.2 38 9 25.1 230 Kagy Boulevard&S.11th LOS B B B c c c D c C Avenue Peak PMHour VIC Ratio 0.35 0.53 0.04 0,85 0,44 0.26 077 0.38 078 Queue Length(95%) 5 a 1 11 4 3 6 5 Movement Group LTR LTR LTR LT R OveraIILOS Control Delay(slveh) 10.0 8,7 74.7 69.8 16.4 KagyBoulevard&S.7lh Avenue LOS B A ® 0 c C Peak AMHour VIC Ratio 0.12 0.05 0.33 0.23 0-10 Queue Length(95%) 1 1 2 1 1 Movement Group LTR LTR LTR LT R OveraIILOS Control Delay(siveh) 93 9.5 352 99.3 16.4 Kagy Boulevard&S.7th Avenue LOS A A E I= C C Peak PM Hour VIC Ratio 005 000 0.39 051 019 Queue Length(95%) 1 0 2 3 1 Movement Group L TR L TR Overall LOS S.111hA venue&Stadium View ControlDelay(s/veh) 91 7.4 Apartments Main Access Peak LOS A A A AMHour VIC Ratio 0.04 0.02 Queue Length(95%) 1 0 Movement Group LTR LTR Overa#LOS S.11thA venue&Stadium View ControlDelay(siveh) 9.6 74 Apartments Main Access Peak LOS A A A PMHour VIC Ratio 0.09 003 Queue Length(95%) 1 0 Movement Group LTR LTR Overall LOS Conlrol Delay(slveh) 88 73 S.111h Avenue&Campus LOS A A A Boulevard Peak AMHour VIC Ratio 0.01 001 Queue Length(95%) 0 0 Movement Group LTR LTR OverallLOS Control Delay(siveh) 89 73 S.111h Avenue&Campus LOS A A A Boulevard Peak PMHour VIC Ratio 0 00 0.03 Queue Length(95%) 0 0 SUD Phase 2 Development Traffic Impact Study Page 6 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 Delay, Level-of-service (LOS), Volume to Capacity (v/c) ratios, and Vehicle Queue projections are used as Measures of Effectiveness (MOE) within Table 1. All intersections, approaches and movements currently operate at LOS "C" or better except for the southbound left lane on South 11 th Avenue, which operates at LOS "D" with 38.9 seconds delay per vehicle during the peak PM hour, and both the northbound and southbound approaches on S 7th Avenue and Kagy Boulevard, operate at LOS "F" in the am and pm hours DEVELOPMENT TRAFFIC PROJECTIONS Trip Generation The proposed apartment complex that would be constructed in Phase 2 is unlike any of the ITE Trip Generation Report land uses since it would be a cross between a Dormitory and a Mid-rise Apartment. Since 2011, when the traffic study for SUD Phase 1 was completed, number of studies have been completed for similar developments. Rather than interpreting a number of studies at various locations across the country, it was decided to develop custom trip generation rates based on actual vehicular traffic accessing the Stadium View Apartments (SUD Phase 1). There are three vehicular access points to the existing complex: the main access to S 11th Avenue, Campus Boulevard, and Arianna Way on the south side of the complex. Three traffic counters were set at each of the accesses for a one-week period in 2016 and a two-week period on Arianna Way in 2015 (see Appendix A). In addition to the counters, manual counts were conducted at the Main Access and the Campus Boulevard access during peak hours. The manual counts also noted pedestrians and bicycles accessing the apartment complex. Correlation between manual and electronic counts confirmed that bicycles were being recorded by the counters. Adjustments to electronic count numbers were necessary and made uniformly throughout the counting period. Table 2 presents the hourly variation in total autos and bikes accessing the Stadium view apartments over the average weekday counting periods. There SUD Phase 2 Development Traffic Impact Study Page 7 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 are 1,672 vehicles entering and leaving the apartment complex and there are 499 beds within the complex. The apartment complex was at full capacity at the time of the counts. The trip generation rates were calculated to be 3.35 AWT trips per resident with 0.12 trips in the am hour and 0.28 trips in the peak pm hour. Table 2. Auto & Bike Access Traffic - Stadium View Apartments Main Access Campus Blvd Arianna Way Totals Hour Average Average Average Average %of Begin Weekday Weekday Weekday Weekday Weekday 0 20 2 2 24 1.4% 1 9 2 1 12 0.7% 2 4 1 2 7 0.4% 3 2 1 1 4 0.2% 4 2 1 1 4 0.2% 5 7 1 3 11 0.7% 6 11 2 6 19 1.1% 7 38 5 8 51 3.1% 8 44 4 10 58 3.5% 9 44 3 12 59 3.5% 10 49 6 15 70 4.2% 11 56 9 13 78 4.7% 12 65 6 13 84 5.0% 13 67 10 18 95 5.7% 14 81 7 15 103 6.2% 15 81 9 17 107 6.4% 16 105 9 21 135 8.1% 17 108 13 19 140 8.4% 18 96 13 18 127 7.6% 19 109 14 19 142 8.511% 20 94 8 21 123 7.4% 21 81 11 13 105 6.3% 22 50 6 10 66 3.9% 23 38 3 7 48 2.9% Total 1399 146 265 1672 100.0% Calculated Vehicular Trip Rates AWT AM PM No. Beds 499 3.35 0.12 0.28 SUD Phase 2 Development Traffic Impact Study Page 8 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 Peak hour manual counts also established trip generation rates for bicycle and pedestrian trips. It was determined that approximately 30% of all trips were made by the pedestrian mode and approximately 10% were made by bike mode. The bike and pedestrian rates were also assigned to the final traffic projections within this study. For the 3,350 square feet of retail development, ITE Trip Generation Report Land Use Code # 814 — "Specialty Retail' was used because it normally provides a relatively conservative estimate of trip generation when specific businesses are unknown. The impact associated with complimentary commercial land uses to residential developments is difficult to quantify because of many unknowns. However, if the commercial facilities are matched to the needs of the residents, the net effect may be a reduction in external vehicular traffic and an increase in localized pedestrian trips within the boundaries of the development. Table 3 summarizes the total vehicular and pedestrian/bike trip generation for the proposed development in Phase 2. The 887 resident units would generate approximately 2,815 auto trips, 312 bike trips, and 1,341 pedestrian/ bike trips on the average weekday. Commercial development would add approximately 157 trips, but approximately 94 trips, would be internal capture trips associated with pedestrian/bike modes made within the confines of the development boundaries and 31 trips would be passerby trips. Therefore, the commercial land use would only add 32 average weekday vehicular trips external to the site. In total, this development would generate approximately 2,690 vehicular trips and 1,653 ped/bike trips that would be new and added to the existing traffic on the surrounding street system. SUD Phase 2 Development Traffic Impact Study Page 9 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,NIT 59102 Table 3. South University District Phase 2 Development Trip Generation Ave.Weekday Peak AM Hour Peak PM Hour No.of Rate Total Total Total Units Units Rate Trips Rate Trips Enter Exit Rate Trips Enter Exit New Development Land Uses Student Apartments 887 Residents 1 2971 2 106 50 56 3 248 159 89 Code 826 Speciality Retail 3.55 1000 sf 4 157 5 24 12 12 6 10 5 5 Total Auto&Bike Trips= 3128 130 62 68 258 164 94 Auto Trips(-10%Bikes)= 2815 117 56 61 232 148 85 Pedestrian Trips(30%of Total) 1341 56 27 29 111 70 40 Trip Class Adjustments Internal Capture-Retail Trips 94 14 7 7 6 3 3 Passerby Traffic-Retail 31 5 3 2 2 1 1 Total Trip Mode and Class Reductions= 125 19 10 9 8 4 4 Total Development Net Auto Trips= 2690 98 46 52 224 144 1 t•T=3.36()p 2-T=0 12(47016 enter) 3-T=0.28(>Q(64%enter) -t-T=44.32()g 5-T=6 84()p(48%enter) 6-T=2 71(>Q(44%enter) Trip Distribution The distribution of vehicular trips was based upon existing directional traffic movements at key intersections adjacent to the development site. Bike/ped distribution was based upon local area attractions and activities and travel distances. Figure 3 is a graphic representation of trip distribution percentages for vehicular trips. Since there are a number of new street segments that will exist within the near future, Figure 3 provides initial and future trip distribution percentages. Approximately 41% of the vehicular trips would have origins and destinations to the north, on South 11 th Avenue, and 37% would have origins and destinations to the north and west using South 19th Avenue. Only 2% of the trips would be to the north and east, using South 7th Avenue, while 15% would have origins and destinations to the east, using Kagy Boulevard east of South 7th Avenue. The remaining 5% of total vehicular trips would have origins and destinations south of the development and accessed by South 19th Avenue. Pedestrian and bicycle trips would all be directed to and from the north. It was assumed, based upon campus attraction densities and walking routes, that 60% of the ped/bike trips would use South 11th Avenue, while the remaining 40% would use South 7th Avenue. It was also assumed that all ped/bike trips would cross Kagy Boulevard at the South 11 th Avenue intersection signal. SUD Phase 2 Development Traffic Impact Study Page 10 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 k b e 2% [ad% ice] [41%] % {�1 [15%] Or�rr O O 17% 0% [17%] [0%] 100% [3%] [ ] innrr AV O adow AM _ _ O 1% 0% n%] [36%] e 0% K InIftl [4%] 3 [0%]—Year 2031 K eler/sr O aev/r-I W- 1% 396 0% 0% A [3%] [4%] 10%] Figure 3. Trip Distribution Percentages Traffic Assignment Site traffic assignments were completed using the trip generation projections in Table 3 and the trip distribution percentages discussed in the preceding section. The initial development traffic assignment assumes that the existing street system would be in-place when the development is complete. While that assumption is not the most likely scenario, resulting traffic impacts on existing intersections can be viewed as the baseline condition. Figure 4 presents the AWT and peak hour site traffic assignments on the street system. It is very clear that all of the traffic impacts would be concentrated on S 11 th Avenue and it intersections. Figure 5 presents site traffic assignment on the future system which includes the Campus Boulevard extension, Graf Street Extension, and the S 11th Avenue extension. The most significant difference between Figure 5 and Figure 4 is the reduction in site traffic on Kagy Boulevard west of S 11th Avenue. SUD Phase 2 Development Traffic Impact Study Page 11 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 P I"— ;0 + N Q ® e PM ®� v 1130 ArdGr AEMP 457 402 K"r At W C4 o no 1 It I I 1076 QLMRb'AI'.W116) w.+ *'1!� r►- .a a!" uni nun,' - ew ,! MIN I. I� W1► �iAM�ln!!wi�� '% .0Aaw.I I r .r• 1343It i 4' 7 N� Figure 4. Site Traffic Volume Assignment - 2016 ConditIons;��� SUD Phase 2 Development Traffic Impact Study Page 12 AW:��, MARVIN &ASSOCIATES 1300 N.Transtech Way Billings, MT 59102 met + ` +Q v ur ws ro ro o y►r vc s -- - - 1, } , L2 « •4 * + S? V qp * • 46 uv yal•o COu ri+1 mr 4IR1 r rin Kn wL ar *u r t 7j— srr wnr s rev + IA ��,� s; ®► e, M6 L, u - SUD Phase 2 Development Traffic Impact Study Page 13 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 TRAFFIC IMPACTS Existing Plus Development Traffic Volumes Figure 6 illustrates the combination of existing am and pm design hour traffic volumes and development generated traffic at each of the key study intersections for full development of SUD Phase 2. Also shown in Figure 6 are the resultant AWT volumes and the percentage increases over existing traffic that would be attributable to the Phase 2 development. In this case, S 11th Avenue, south of Kagy, would have the highest volume of site generated traffic and also the highest percentage increase of any of the area streets at 256%. It should be noted that, normally traffic impacts on streets that are less than 10% are not considered to be significant because daily traffic variations on any street routinely exceed 10%. SUD Phase 2 Development Traffic Impact Study Page 14 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings, MT 59102 62 film, I Wad >�G 14750—Jh�wr''i'r TMrn' 1470 ITA T—T� a� FIT� OF 0 IR CEO 4-�—n I�j W i INC D w o ne 1Z00 t '�a [6B1%] AW y� .luu�unl U o A .'a � . ayWIh1�JA1tI� 111.111 nt,mile a; IIi 1345 W� t�• M Mul—t , / ...M.�.�.wV�'. .M-I1111f Illp e' �• ' � fi, s NN • i '�►iY re o •� _ PM I ' Figure 6. Existing (2016) Plus Site Traffic Volumes' SUD Phase 2 Development Traffic Impact Study Page 15 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 Capacity Capacity calculations (see Appendix B) indicate that all approaches and all movements at the key intersections would be similar to existing LOS at all intersections except that some additional movements would operate below "C" at the S 11 th Avenue intersection, if the Phase 2 South University District development existed today. Table 4, below, presents a summary of the MOE's for each intersection and for each approach lane at each of the intersections. In comparing Table 4 to Table 1, it can be seen that appreciable variations in the LOS, delay and v/c ratios occur for individual movements on the northbound and southbound legs of the S 11th Avenue and Kagy Boulevard intersection in the pm hour. At the S 7th Avenue intersection with Kagy Boulevard, the northbound and southbound legs would remain at LOS "F" during both the am and pm peak hours. Queue lengths would vary within individual lanes, with the most critical being on the eastbound and westbound through lanes and on the northbound left-turn lane during the peak pm period. All of the minor street accesses on S. 11th Avenue to SUD Phase 1 and 2 would operate at LOS "B" or better for existing plus site traffic conditions. Typically, a two lane streets in an urban environment can carry between 6,000 and 9,000 vehicles per day and still operate at LOS "C". Three lane streets can carry up to 18,000 vehicles while 5 lane streets max-out at approximately 30,000. Thus, it would appear that S 11 th Avenue would still be within its ideal operating range, while Kagy Boulevard is and will be well above its ideal operating range. SUD Phase 2 Development Traffic Impact Study Page 16 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 Table 4. Existing Plus Site Traffic Capacity Analysis Summary Intersection MOE EB WB NB SB Intersection Mow,n-rx L TR L TR I L TR OVERALL Control Delay(s/veh) 10.7 8.6 14.6 296 26 5 27 2 29.3 27.7 19,6 Kagy Boulevard&S.11111 LOS B A B C C C C C B AvonuePeak)IMHout VIC Ratio 0.31 0.56 012 0.82 016 027 0.51 0.34 065 QueueLenqthJ95V 5 8 1 11 2 2 3 4 YOWNnely Gr L TR L I R I R L TR OVERALL Control Delay(s/veh) 14.0 11.3 13.8 29.9 36.0 25.2 92.9 26,4 29.1 KagyBoulevard&S.11th LOS B B B C D C = C C Avenue Peak PMHour VIC Ratio 0.35 0.60 0.13 0.85 0.71 040 1.00 0.52 0.85 Queue Length f959Q 7 10 2 11 10 5 7 9 Aknevnm Ormp LTR LTR tll. LT R OveraALOS Conlral Delay(s/veh) 10.1 8.7 786 73.0 16.4 KagyBoulevard&S.7lh Avenue LOS B A = c C PeakAMHour VIC Ratio 0,12 0.05 0.34 0.23 0.10 Queue Len th t959' 1 1 2 1 1 04emwGOV LTR L7R 11R LT R OverallLOS Control Delay(s/veh) 9.4 9.6 38 3 113.2 16.8 Kagy Boulevard&S.71h Avenue LOS A A E = C C PeakPMHour VIC Ratio 0.05 0100 0.42 055 0.20 Queue Length(95%) 1 0 2 1 3 1 mawalear Gro(y) L TR L7R Overall LOS S.I 1th A venue&Stadium View Control Delay(s/veh) 10.1 7.5 Apartments Main Access Peak LOS B A A AMHour VIC Ratio 0.05 0.06 Queue ton th(95)5) 1 0 Mtn"WN Group Ill" LTR S.111h Avenue&Stadium View Control Delay(s/veh) 124 7 9 Apartments Main Access Peak LOS B A A PMHour VIC Ratio 013 012 Queue Length(95%) 1 0 Afowment C,rou i Ill, !H Overall LOS Control Delay(s,Veh) 9-6 74 S.111h Avenue&Campus LOS A A A Boulevard Peak AM Hour VIC Ratio 0.04 004 Queue Len th(95 1 0 Alarmenl Group LTR t 7I; OW,?#LOS Control Delay(sNWh) 11.1 77 S.111h Avenue&Campus LOS B A A Boulevard Peak PM Hour V/C Ratio 007 0.08 Queue L en th(95V 1 0 AfaawitYX Group 111? LTR tlR LTR Okvdatos Control Delay(s/veh) 9.6 8.4 7.3 7.3 SUD Phase 2AccessA&S11th LOS B A A A C Avenue Peak AMHour VIC Ratio 0.04 0.02 0.00 0.02 Queue Length 95% 1 1 0 1 1 Asofty,xvit cdow LTR LTR LTR LTR 0verallLOS Control Delay(s/veh) 10.2 8.5 7.5 7.3 SUD Phase 2 Access A&S 11th LOS B A A A C Avenue PeakAMHour VIC Ratio 0.07 0.04 0.00 0.02 Queue Length 95% 1 1 0 1 SUD Phase 2 Development Traffic Impact Study Page 17 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 Future Traffic The City of Bozeman's Municipal Code (BMC) requires that all traffic impact studies analyze all arterial and collector street intersections within a 0.5-mile distance from the site development. The BMC indicates that all intersections must operate at LOS "C" or better in the future, which is defined as 15 years beyond the development year. For this development, several previous studies have been completed in an effort to develop design data for the Graf Street and the S 11th Avenue extensions as well as a TIS for the Yellowstone Theological Institute development along the Graf Street Extension. The prior efforts resulted in models that redistributed existing traffic to the planned street system and projected development traffic growth as well as external traffic growth on the street system. All of the previous traffic projections were combined and adjusted to year 2031 conditions in order to determine a reasonable estimate of future traffic volumes at the key study intersections. It can be seen that the extension of S 11 th Avenue would carry approximately 4,400 AWT in the year 2031 and the Graf Street Extension would have an AWT of approximately 4,000. The majority of traffic on both of these extensions would be traffic that would have otherwise been on Kagy Boulevard east of S 11 th Avenue. Figure 7 presents the AWT and peak hour traffic projections that resulted from the traffic algorithms used in this study. Since the new street extensions would place the site within a 0.5-mile distance of two new intersections (S 19th & Stucky Road and Graf Street & S 11th Avenue) traffic projections at those intersections are also shown in Figure 7. SUD Phase 2 Development Traffic Impact Study Page 18 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 ry h7 4a .4.. 14 AV 4 Li q ® 1 ® 1 re g ram'—." 07r: 41 1 * _ 1 _ 1 CCp 1 � 3AY WL'! SAY 4Hl C !® _qP �f 1 ® I 1 1 i 1 & aw Iws T 1 1 �1 1 g` .• 1 E 1 1 � 1 �OI � 1 1 1 1 14Iwo A a k. 1 t L C1 1 L 1 1 U1Y 91LL'/ ;GAO iAtl 4Ni 4 1 SUD Phase 2 Development Traffic Impact Study Page 19 MARVIN&ASSOCIATES 1300 N.Transtech Way Billings,MT 59102 Future Conditions Plus Site Traffic Figure 8 illustrates traffic assignment volumes associated with full development of the proposed site (Figure 5) combined with year 2031 traffic projections (Figure 7). The traffic volumes shown in Figure 8 are used to evaluate future capacity conditions in satisfaction of the BMC requirements. Future Capacity Table 5 (page 22) presents a summary of the MOE's for each intersection and for each approach lane at each of the intersections in the year 2031. In calculating the future capacity, it was assumed that all of the future street improvements and extensions would be constructed as currently planned. Kagy Boulevard would have a five lane section and traffic signals at both S 11 th Avenue and at S 17th Avenue. The S 11 th Avenue extension would have two-lane traffic with bike lanes and its intersection with Graf Street would be a single lane roundabout. The intersection of S 19th Avenue and Stucky Road/Campus Boulevard would add a fourth signal indication and S 19th Avenue would have 5 lanes of traffic. Capacity analysis results indicate that all of the intersections and lanes would operate at LOS "C" or better in the year 2031 with projected future traffic plus site traffic conditions. It should be noted that the intersection of N 7th Avenue and Kagy Boulevard could feasibly be a roundabout and operate at a better LOS than with a traffic signal. SLID Phase 2 Development Traffic Impact Study Page 20 ■4 M1 7' ! to O e..Y tip* LLw � r�r A �� re■ i _ _ ``♦■ a _� 1 ! � � �,� � � � 1 0 � o uw a ■ .�■ i 1j r ■T! p EE w • O � •1 � : A a • 11 � O r� cs • o' A 1.1 ♦ ow 11 w■• 802-, THE CITY OF BOZEMAN 20 E. OLIVE • P.O. BOX 1230 V BOZEMAN, MONTANA 59771-1 230 ,t n ENGINEERING DEPARTMENT 9r`�AIJV CO. PHONE: (406) 582-2280 • FAX: (406) 582-2263 STORY MILL COMMUNITY PARK TRAFFIC IMPACT STUDY Prepared for Design Workshop, Inc. 120 East Main Street Aspen, Colorado 81611 970 • 920-4005 Prepared by LSC Transportation Consultants, Inc. 2690 Lake Forest Road, Suite C P.O, Box 5875 Tahoe City, California 96145 530 • 583-4053 June 10, 2016 LSC#167090 HOME OF MONTANA ff.,ATE UNIVERSITY GATEWAY TO YELLOWSTONE PARK Boz�'rjr THE CITY OF BOZEMAN V �x 20 E. OLIVE • P.O. BOX 1230 * * BOZEMAN, MONTANA 59771-1 230 9�C 8 O� ENGINEERING DEPARTMENT TABLE OF CONTENTS SECTION PAGE 1 INTRODUCTION ............................ .....................................................................I..........I ProjectDescription.........................................................................................................I Scopeof Study...............................................................................................................2 2 EXISTING CONDITIONS..................................................................................................3 Roadway Characteristics................................................................................................3 Existing (2016) Traffic Volumes...................................................................................5 3 PROPOSED CONDITIONS................................................................................................9 ProjectDescription.........................................................................................................9 Trip Generation, Distribution, and Assignment.............................................................9 4 LEVEL OF SERVICE.......................................................................................................19 Description...................................................................................................................19 Level of Service Standards..........................................................................................19 AnalysisMethodology.................................................................................................20 Levelof Service Analysis............................................................................................20 5 TRAFFIC IMPACTS, RECOMMENDATIONS AND CONCLUSIONS .......................23 Impact on Traffic Volumes..........................................................................................23 IntersectionLOS Impacts ............................................................................................24 Signal Warrant Analysis ..............................................................................................25 RoadwayLOS Impacts................................................................................................25 Analysis of the Need for New Turn Lanes ..................................................................25 Recommendations........................................................................................................27 Conclusions..................................................................................................................28 APPENDIX A: TRAFFIC COUNTS APPENDIX B: LEVEL OF SE VICE DESCRIPTIONS APPENDIX C: INTERSECTION LOS REPORTS APPENDIX D: ROADWAY LOS CRITERIA APPENDIX E: TURN LANE WARRANT CRITERIA LIST OF TABLES TABLE PAGE 1 Story Mill Park Trip Generation....................................................................................... 10 2 Story Mill Park Trip Distribution ......................................................................................13 3 Story Mill Park TIA—Intersection LOS............................................................................20 Stay Mill Park LSC Transportation Consultants, Inc. Traffic Impact Study Page i HOME OF MONTANA STATE UNIVERSITY GATEWAY TO YELL WSTONE PARK 802�',jt THE CITY OF BOZEMAN 9x 20 E. OLIVE • P.O. BOX 1230 * BOZEMAN, MONTANA 59771.1230 t' 8 o, Ory Mill Park—Roadway I� VNEERING DEPARTMENT ....22 .................................................... 9'�I'jv � Story Mill Park—Tra icEVo�lume�mpacts...FAX. (406) 582-2263 .......................................................23 6 Story Mill Park—Year 2018 PM Peak-Hour Intersection Traffic Volumes .....................26 LIST OF FIGURES FIGURE PAGE 1 Story Mill Park Site Location, Lane Configuration and Intersection Controls .................. 4 2 Story Mill Park AM and PM Peak Hour Existing No Project Volumes..............................6 3 Existing Daily Traffic Volumes...........................................................................................8 4 Story Mill Park Project Generation AM and PM Peak Hour Traffic Volumes.................14 5 Project Generated Daily Traffic Volumes .........................................................................15 6 AM and PM Peak Hour Traffic Volumes with Story Mill Park........................................16 7 Existing Daily Traffic Volumes with Story Mill Park.......................................................17 LSC Transportation Consultants,Inc. Story Mill Park Page ii Traffic Impact Study HOME OF MONTANA ffPTE UNIVERSITY GATEWAY TO YELLOWSTONE PARK Chapter I INTRODUCTION The purpose of this traffic engineering study is to determine the impacts of the traffic generated by this proposed development on the surrounding roadway infrastructure. This study will determine if mitigation is required to keep the roadways operating safely and at capacity levels acceptable under the current code. This report is based on local ordinances, and provides a complete analysis of the intersections identified for analysis. The existing and existing plus project traffic conditions are analyzed and discussed in detail in the subsequent sections. This report examines the full build-out of the site-generated traffic volumes, as well as the operational analyses of study intersections located within the study area. This report documents the findings and conclusions of a Traffic Impact Study (TIS) conducted for a proposed site plan for property located in the City of Bozeman, Montana. PROJECT DESCRIPTION The project proposes a new community park located south of and adjacent to Bridger Drive (State Route 86) in Bozeman, Montana. The park is proposed to be approximately 60.24 acres in area and is proposed to contain the following amenities: • Community Center(11,760 square feet) • Teaching Garden/Food Forest • Trails • Event Lawn • Amphitheater • Picnic Pavilion • River Access • Playground • Nature Walk • Fishing Access • Dog Park(0.5 acre) Access to the project site is proposed to be provided via two driveways along Bridger Drive and one driveway on Story Mill Road. Specifically,the western driveway forming the south leg of the Bridger Drive/Bridger Center Drive intersection would provide access to the proposed Community Center and park. This driveway currently provides access to the Boys & Girls Club. In addition, a new driveway forming the south leg of the Bridger Drive/Birdie Drive intersection would provide access to the park. The existing driveway located on the south side of Bridger Drive between Bridger Center Drive and Birdie Drive, which served the previous mobile home development,would be removed as a part of the project.Additionally, a driveway located on Story Mill Road ("L" Street) immediately south of the Story Mill Road/Story Mill Spur/L Street intersection would provide access to the proposed dog park, fishing access, and trails. Finally, the project proposes to construct improvements along East Griffin Drive in order to enhance conditions for non-auto travel modes (such as bicyclists and pedestrians). Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 1 254 SCOPE OF STUDY This traffic engineering study documents the existing and proposed conditions, traffic data, and Level of Service in accordance with the requirements of the City ordinances. The scope of the study was defined by LSC Transportation Consultants and the "TIS Preparation Guidelines" provided in the Greater Bozeman Area Transportation Plan(Section 10.5). The following intersections were identified for analysis: 1. Bridger Drive/Griffin Drive/Rouse Avenue 2. Bridger Drive/Bridger Center Drive/Site Access 3. Bridger Drive/Birdie Drive 4. Bridger Drive/Story Mill Road 5. Story Mill Road/Griffin Drive In addition, the following roadways were identified for analysis: • Rouse Avenue, South of Griffin Drive • Bridger Drive, Between Griffin Drive and Bridger Center Drive • Bridger Drive, Between Bridger Center Drive and Birdie Drive • Bridger Drive, Between Birdie Drive and Story Mill Road • Bridger Drive, East of Story Mill Road • Griffin Drive, West of Rouse Avenue/Bridger Drive • Story Mill Road,North of Bridger Drive • Story Mill Road, South of Bridger Drive The results of this traffic study are used to develop recommendations to mitigate project traffic impacts. This analysis considers two scenarios: 1. Existing (2016)No Project 2. Existing (2016)Plus Project This TIS is prepared for submission to the City. Traffic related issues addressed in this report are consistent with the requirements of the City's Code of Ordinances Section 38.41.060. The issues are as follows: 1. Existing traffic conditions 2. Site generated traffic volumes and their distribution and assignment 3. Level of Service analysis with and without the project 4. Recommendations for mitigation of traffic impacts 5. Peak-hour signal warrant conditions LSC Transportation Consultants,Inc. Story Mill Park Page 2 Traffic Impact Study 255 Chapter 2 EXISTING CONDITIONS The existing infrastructure and operational traffic conditions in the vicinity of the site were documented. The following discussion presents information regarding the project site, turn volumes, and traffic conditions in the study area. Figure I displays the existing roadway lane configurations and traffic controls. ROADWAY CHARACTERISTICS The roadways in the vicinity of the site area are State Route (SR) 86 (Rouse Avenue-Bridger Drive), Story Mill Road, Birdie Drive, Bridger Center Drive, East Griffin Drive, Story Mill Spur, and Rouse Avenue. The pertinent information regarding these roadways is described below. SR 86 (Rouse Avenue-Bridger Drive)provides access from downtown Bozeman through the Bridger Canyon to the northeast of the City of Bozeman. Rouse Avenue runs in a north-south direction from downtown Bozeman to north of Interstate 90. Rouse Avenue has a two-lane cross- section through the study area. There is a left-turn lane at the signalized intersection with Griffin Drive, but no other turn lanes are provided. There is a grade separation at Interstate 90 at Rouse Avenue, but there is no direct access to the freeway. The posted speed limit on Rouse Avenue north of Interstate 90 is 35 mph. At the intersection with East Griffin Drive, Rouse Avenue continues to the north as Bridger Drive. Bridger Drive continues to the east and assumes an east- west alignment through the study area. Bridger Drive continues a two-lane cross section through the study area. There are currently no turn pockets provided at intersections. The posted Speed limit on Bridger Drive is 35 mph. East of Story Mill Road, the speed limit increases to 45 mph. SR 86 is classified as an urban minor arterial by the Montana Department of Transportation (MDT). The City of Bozeman classifies SR 86 as an urban principal arterial. Griffin Drive runs in an east-west alignment between Story Mill Road and North 7th Avenue. West of SR 86, Griffin Drive is classified as an urban minor arterial by the Montana Department of Transportation and as an urban principle arterial by the City of Bozeman. West of SR 86, Griffin Drive has a two-lane cross section with a right-turn lane provided at the signalized intersection with SR 86. The posted speed limit west of SR 86 is 35 mph. East of SR 86, Griffin Drive is considered a local roadway and has a posted speed limit of 25 mph. This section of Griffin Drive has a narrow cross section and traverses two bridges. This portion of Griffin Drive traverses the study area. Part of East Griffin Drive is proposed to be improved in order to better accommodate non-auto modes, such as bicyclists and pedestrians as part of the proposed Story Mill Park project. Story Mill Road is classified as an urban collector by the Montana Department of Transportation and as an urban major collector by the City of Bozeman. Story Mill Road runs in a north-south direction and has a two-lane cross section. North of SR 86, Story Mill Road provides access to residential and rural areas. The posted speed limit on Story Mill Road north of SR 86 is 35 mph. South of SR 86, Story Mill Road connects with L Street,which provides a second grade separation under I-90 on the northeast side of Bozeman connecting to downtown. The posted speed limit on Story Mill Road south of SR 86 is 25 mph. The intersection of Story Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 3 256 C N O � U IM 0 — O N C U) H J A s O in CU O � C � C as W C O C df � Ey � O ® s �j LL C O f0 O .1n1.y]rein]d/.l•. J ; a) a Y 03 I Q M o Pa 11m NwS y ww. D— g 0 0 N O ram, ?; ti �m i 4 c 0` ago fY O ar41 U �o N o m y ' ao) o OI �Q m ,v_ r m m e m .d_, 0 m SSe�'Jb'Bll (n 'enyesnoa •N u �� SSOMV elig -gyp slp�lg {� Peso ad 0 L Mi I'"tiOiS C r r at0 Coloa v N =4 OI ` OI 4 1 E� 4r `w 41, m 0 LSC Transportation Consultants,Inc. Story Mill Park Page 4 Traffic Impact Study 257 Mill Road at SR 86 is stop-controlled for both of the Story Mill Road intersection approaches and free for traffic on SR 86. Bridger Center Drive is a short local roadway that extends to the north of SR 86. Bridger Center Drive provides access to industrial park land uses. The Bridger Center Drive approach to the SR 86 is stop-controlled. The south leg of this intersection,which currently provides access to the Boy and Girls Club,would provide access to the proposed project site. Birdie Drive is a local roadway that provides access to residential neighborhoods north of SR 86. There are commercial park type land uses located in the vicinity of the intersection of SR 86/Birdie Drive. The posted speed limit on Birdie Drive is 25 mph. The Birdie Drive approach to the intersection with SR 86 is stop-controlled. A proposed park driveway would form the fourth leg (south leg) of this intersection. Figure 1 shows the project area, study intersections, lane configuration, and intersection controls. EXISTING (2016) TRAFFIC VOLUMES Existing traffic volume data is the basis for the analysis of the capacity and safety of the roadways. Intersection traffic volumes are estimated for the AM and PM peak hours, and daily traffic volumes are estimated for the study roadway segments. Intersection Traffic Volumes Intersection turning-movement counts were conducted at the Bridger Drive/Rouse Avenue/ Griffin Drive and Bridger Drive/Story Mill Road intersections on Tuesday, October 20, 2015 by Robert Peccia and Associates as a part of the update to the City of Bozeman Transportation Plan. The Bridger Drive/Bridger Center Drive/Site Access and Bridger Drive/Birdie Drive intersections were counted on Tuesday, April 12, 2016, and the Story Mill Road/East Griffin Drive intersection was counted on Wednesday, April 13, 2016 by Stahly Engineering & Associates, Inc as a part of this project. As per the City of Bozeman Transportation Plan, all intersection counts were counted on a regular weekday (Tuesday, Wednesday, or Thursday) during a non-holiday week from 7:00 AM—9:00 AM and 4:00 PM—6:00 PM. The count data is contained in Appendix A. MDT provides adjustment factors in order to annualize the traffic counts. These adjustment factors are applied to the count data according to roadway classification, month of the count, and day of week of the count. The resulting AM and PM peak hour intersection turning-movement design volumes are shown in Figure 2. Roadway Segment Traffic Volumes Roadway Annual Average Daily Traffic (AADT)volumes are provided by MDT. The most recent AADT volumes are from 2014 and are available for the following roadway segments: • Rouse Avenue, South of Griffin Drive • Bridger Drive, Between Griffin Drive and Bridger Center Drive • Griffin Drive, West of Rouse Avenue/Bridger Drive • Story Mill Road, South of Bridger Drive Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 5 258 � \ • | . � � ) i _ m m _ § | WE 0 \ \ M t E ® ® U) ! / 7 \ } \ LO . w ^ t a Q { 0 ~R— / � � � `5 k © , 2 _ _ ! \ o - w § q :3 / � � • " � \ ! �\ ° E \ • @ i « . f 2 --- � m m mG ® � § USCD 0Ln 6 — ` -J «L: ° �� GtM\ �i� I ©E M ° k\F — �p S z ~ o u . _ b w e a .m mG § /4 6 !(; wo V 200 { § R J � LSC Transportationcm+antAI. Story Mill Park Page& Traffic Im w Study 259 AADT for the remaining roadway segments is estimated by applying a daily-to-peak hour factor to the two-way peak-hour volumes. This factor is estimated based on the ratio of AADT to the peak-hour volume on known segments. This ratio is then multiplied by the peak-hour volume on the other roadway segments to estimate the AADT on those segments. The resulting roadway segment design volumes are shown in Figure 3. Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 7 260 � � o r Srar Fanc b o -mid CS Vxr{wg Ra+pane A o NIlk 2 V.m.L.:Cgn cn O 4 C 9fbx'IkNP t yV a 0A '.. U- M o _ t� W bi z a 5 w lo 01 - � �,yV,PO.FEAmxR � �14x1V2 YJd,(L'.�ti a treuara Eve /1 ! I t � /I / I % Fs i i' ! X M« t / I LSC Transportation Consultants,Inc. Story Mill Park Page 8 Traffic Impact Study 261 Chapter 3 PROPOSED CONDITIONS The proposed development will add traffic to the roadway system. The project location and the size of the project are important elements that need to be considered to determine the impacts of this development on safety and capacity. It is also important to examine how the project will operate with the existing transportation system, estimate how much new traffic will be generated, and predict where traffic generated by the site will be distributed. PROJECT DESCRIPTION The proposed community park is approximately 60.24 acres in area and is proposed to contain the following amenities: • Community Center(11,760 square feet) • Teaching Garden/Food Forest • Trails • Event Lawn • Amphitheater • Picnic Pavilion • River Access • Playground • Nature Walk • Fishing Access • Dog Park(0.5 acre) For purposes of this analysis,the project is assumed to be 100%complete under `existing plus project' conditions. The project proponent indicates that special events (lawn events and amphitheater events) and event traffic would be limited to late evenings and weekends.Note that there is an existing Boys and Girls Club at the location of the proposed community center. In order to remain conservative in this analysis, no credit is applied for existing site-generated traffic. TRIP GENERATION,DISTRIBUTION,AND ASSIGNMENT Trip Generation The first step in the analysis of future traffic impacts is to prepare an estimate of the number of trips generated by the proposed project. Trip generation is the evaluation of the number of vehicle-trips that will either have an origin or destination at the project site. Daily vehicle trips and peak-hour vehicle trips must be determined in order to analyze the potential impacts from the proposed project development. A summary of trip generation for the proposed project is presented in Table 1. Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 9 262 IA F I O t7 m 0 N 00 -0N m O ry ` u = Y o d d 0 m I O m N 0 00 M m l[) m :2 d N a c n I O O m N 00 O O O O O g n m f. VF Ol I .0- 0 0 0 0 0 M N ? m t0 a N Fg O n n 0 > M v l o o ro o 0 0 00 m o 0 0 0 0 � S � MOQj ed q Q C N I m 0 0 0 0 0 N N m (h N o p g •}� 0 o ON I N M -It 0 � f00 f0 R N N N l7 7 9 ; K -LL A a p0 (p M 0 c 5 5 m 4' � o v000000 eeee '_ � °i g C .0 U'1 0 0 0 0 0 0 0 I o 0 0 0 ° o s m 0 0 o 11 m o 00 0 0 0 0 0 '„ 3 N I m 0 I7 - 4'1 n 0 0 ' 11� In 1q: _ ~ 0 0 0 0 - 0 0 0 0 0 0 0 Y N O O m m U] O O O O O O O (D I rn o m o n o 0 o I a o 0 0 0 0 0 0 0 0 0 0 0 0 m 4 6 a g o g O o o W rn In u1 0 0 w a 0 0 0 0 0 Y Y Y r 5— 0 0000000 0000 aIm- U 1° LO O m U) 0 0 0 0 0 V 10 In p O n V b O O 0 0 0 .01 0 �0 0 0 - 0 0 0 0 0 0000 � = C Y O O O m O O o O 0 0 0 0 0 m o 0 0 lb 0 0 0 0 6 0 0 0 0 0 0 0 c 0 0 0 0 0 0 0 0 g ti W W 'e 2 O rn o m m o 0 0 0 o 3 Q c O O1 f0 O O O O O ( O N O N 00000000 0000 a » dW v _ Of aR: t1 uni v ro (q m o 0 o I m o ao° o C v Y 4 tpp ¢q Q N M CO N N N N O N O N tCj j Q 61. n p n 9 a -E.6 ✓+ w Y y .N. � � w � t 8 5� u & c �Y n yi u� w 4)i m m m cm m m m � n n n 2- a 2- n Y o n ) A) L) 0 U . '0 U � Y Y nc n �g wa a a a aaaa a aa Q = ; ° u~c~ caFF. a o y �•2,W� A m c ° � W c n� r o N 0 o 0 0 0 o 0 o n 0 N pZf f0 N Ol c9 N 0 �y N G (.7 g Q $ q C 4 c L` Q V H ,°n 6 ° +� la K �F:� •°� �N G ° 3 n .` lil a n Q Q Q Q Q Q Q Q Q Q Q Q v e a .6' �p 0 vzzzzzz 'zzz z z z o Y � AvS v y � N � H � FyyF iD{I1 g Y O B o� •te a 3 , W d W W Q 5 y L W Z CW =�-I F Y RI N C a u t r f:v° b o W Q Q ° c o n `v,m •Y ; L Z, M ozz 'z 'zzzzzz z z z u � � °�, ° off-�E iIrti o o s g N 9 9�i Y e K V Q. o W gaaroaa $p� � c -o n m m 5 m E O m G G fi o W E Y Y z s F3 ik O y0 0 "' v a o IC- a Q c c ° a u o n26 C :7 y 0. w v m ° o g cY c Fa G Y pc p� LLI c T a U 'E O D_ O C yc ar 0 aOI > c' N �I IyyI OI OI pp ° u 2 c LY > gg U J n > > E U U N K CJ N Y of W ID (� (� O Y gF V tW K�Y)LL~ W KO� m .c rn E E E T'S S E E '� o a L c J c 3 .. o `v? b mooU1 t a. o 4 ¢ C7T o e om5aauu m Y Y Y Ww o o U L) I I . I I I LLy 0 w a I w 22222 2222213§Y 8 LSC Transportation Consultants,Inc. Story Mill Park Page 10 Traffic Impact Study 263 First,trip generation is evaluated for a typical busy summer day (the "design day")without a special event.Next, the trip generation associated with special events is estimated, based on a worst-case scenario with regards to event traffic.However, for purposes of this analysis, event traffic is not included in the design volumes, as the project proponent indicates that special events (lawn events and amphitheater events) and event traffic would be limited to late evenings and weekends. Trip Generation—Typical Summer Day (Design Day) Information regarding trip generation is generally contained in the Institute of Transportation Engineers (ITE) Trip Generation Manual (9th Edition, 2012). However, the trip generation of a park varies substantially depending on the specific uses. The proposed uses in Story Mill Community Park do not fall wholly within any of the park definitions in the Manual. The trip generation analysis is presented in Table 1. As shown, the basis for the trip generation analysis of the proposed park is the "Regional Park" land use defined by ITE. The description that ITE provides for the "Regional Park" land use includes many land uses listed in the park program, such as hiking trails, river access, picnic facilities, and office space. However, the ITE description of"Regional Park" does not necessarily include the use of a free-standing community center with regular staff, activities, and events. The ITE description also does not include any mention of a dog park. Therefore, trips associated with these uses were estimated based upon the number of persons expected to use these facilities, factored to convert person- trips to vehicle trips. Community Center Trip Generation The park program lists the expected uses of the community center, and the expected number of participants for each use. These uses are shown in the table. The daily trip rate for each use assumes one round-trip, meaning two one-way trips (one entering and one exiting), for each participant. The daily trip rates also reflect increased vehicle occupancy for carpooling. For example, many uses are estimated to have a carpool rate of 20 percent. Therefore, the trip rate reflects an average vehicle occupancy rate of 1.11 persons per vehicle for uses where carpooling is expected. Additionally, trip rates for facility uses for children below driving age—such as the proposed day camp—reflect that these participants would be dropped off and picked up by an adult who would not remain at the park for the duration of the activity. Each drop-off"trip" and each pick-up "trip" actually generates two one-way trips at the site access points. This results in the potential for each participant to generate up to four one-way trips at the project access. The daily trip rate for the preschool reflects that parents will remain on site for the duration of this program and 20 percent will carpool. The daily trip rate for the after-school programs assumes that the participants will arrive at the site by bus, but will be picked up by parents. Peak-hour trip generation is based on the time-of-day schedule of activities provided by the project proponent. Uses with scheduled start or end times within the adjacent street peak AM and PM periods (7:00-9:00 AM and 4:00-6:00 PM) are estimated to have 75 percent of their participants arrive or depart during the corresponding design peak hour. Uses with a start or end time within an hour of the adjacent street AM and PM peak hours are estimated to have 10 percent of their participants generate a trip during the corresponding peak hour. Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page H 264 Dog Park Trip Generation ITE does not provide standard trip generation statistics for a dog park. As the ITE land use description for"Regional Park"does not mention dog parks in the sites surveyed, the trip generation of the dog park is estimated in addition to the community park use, in order to remain conservative in this analysis. Based on discussions with the project team and the anticipated use levels at the dog park, about 15 daily one-way trips and 2 peak-hour trips in the AM and PM are expected to be generated by this use. Reductions for Non-Auto Trips The standard ITE trip rates are based on vehicle counts at driveways and as such, they reflect a typical level of non-auto travel. Considering the extensive trail system, an additional 5-percent reduction is applied to the "Regional Park"trip generation to reflect trips made to/from the proposed park via non-auto modes. It was reported that approximately 20 percent of the community center employees would bike to work. However, to remain conservative in this analysis and to account for the fact that employee housing location may change over time, a 10 percent non-auto reduction is assumed for community center employees. Also to remain conservative in this analysis, no further non-auto mode reductions are assumed for other proposed uses of the community center and the park. Total Trip Generation on Design Day As shown in Table 1,the proposed Story Mill Community Park is estimated to generate a total of approximately 638 daily one-way vehicle trips on a typical weekday without an event scheduled. The project is estimated to generate 41 vehicle trips (28 entering and 13 exiting) during the AM peak hour of the design day, and 99 vehicle trips (55 entering and 44 exiting) during the PM peak hour. The traffic operations analysis is based on these figures. Trip Generation—Special Events Trip generation for the proposed amphitheater and the proposed event lawn is estimated using a person-trip analysis based on the stated capacity of each of these proposed venues. The daily trip rate assumes one inbound and one outbound trip per seat or attendee with an average vehicle occupancy of 2.5 persons per vehicle. Peak-hour trip generation for event is dependent on the schedule and duration of the event and could vary greatly depending on the type of event. Peak- hour trip generation is estimated at 5 percent of daily trips during the AM peak hour and 50 percent of daily trips during the PM peak hour. This estimation for the PM peak hour is based on a conservative worst-case scenario in which all event attendees would depart from the site during the PM peak hour. Trip generation for both of the event venues also includes trips generated by event staff. A staffing level of one event staff per 20 event attendees is assumed, based upon average employee-to-attendee ratios for convention-type uses. Each staff member is assumed to generate one entering and one exiting trip at the site access on the day of the event. Staff are LSC Transportation Consultants,Inc. Story Mill Park Page 12 Traffic Impact Study 265 conservatively assumed to have a vehicle occupancy rate of 1.0. Approximately 25 percent of staff are assumed to arrive during the AM peak hour and 50 percent of staff are estimated to generate an outbound trip during the PM peak hour. As shown in the lower portion of Table 1, the worst-case scenario of two concurrent special events at the proposed Story Mill Community Park would generate an additional 450 one-way daily vehicle trips, with 27 entering trips during the AM peak hour and 213 exiting trips during the PM peak hour. For purposes of the traffic operational analysis, neither of the proposed event venues are assumed to schedule an event during typical weekday commuter peak hours. As such, the special event trips are not reflected in the intersection and roadway capacity analyses. Trip Distribution and Assignment The distribution of traffic arriving and leaving the project site is identified based upon the distribution of traffic arriving and leaving the project site and is estimated based on population distribution in the City of Bozeman (as reported by the United State Census Bureau on the American Fact Finder website), regional access patterns, existing turning-movement volumes, and the location of complementary land uses within the area. The trip distribution pattern assumed for the Story Mill Park project is shown in Table 2. As shown, the majority of trips (63 percent) are expected to travel to/from Rouse Avenue to the south. TABLE 2: Story Mill Park Trip Distribution Origin / Destination Distribution Rouse Avenue, South of Griffin Drive 63% Griffin Drive, West of Rouse Avenue 21% Bridger Drive, East of Story Mill Road 5% Story Mill Road, North of Bridger Drive 1% Story Mill Road, South of Griffin Drive 9% Birdie Drive 1% Tota 1 100% Source: LSC Transportation Consultants, Inc. Story Mill TIA.xlsx The project-generated turning-movement volumes are calculated by applying the distribution to the trip generation. The Story Mill Park peak-hour project-generated intersection turning movements are provided in Figure 4 and the daily project generated traffic volumes are provided in Figure 5. The project-generated volumes are added to the existing turning-movement volumes to create the existing 2016 intersection turning-movement volumes with Story Mill Park, as displayed in Figure 6. The daily traffic volumes with Story Mill Park are displayed in Figure 7. Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 13 266 o- a`�i E O > ¢> U U � f0 f0 C ~ ~ F a O N t r ' Wide Scar Lane O I ` g N vkcw.a K_ F- N = VaNVA4 Cw O C� y G d vAc� 14 N a > a 0 aMn xva�..�r fi O `m 0 V J V �O O Pa ii!w n ais w 1 � �k a ro r; p sse»yeas y m •any asnoa C M sseooy ai!S ;6 aTIA P6S0 ajd 'Pa II!W tiolS a(7 o a� o c~v ao o 1 tr. a o o y m tY o o m o 0 "t LSC Transportation Consultants,Inc. Story Mill Park Page 14 Traffic Impact Study 267 / \ ! k \ f ! f § } % LO m_ { ._ S f �! m __� «� i ® ^ k E 0 w � •- i, t ` LU \ � % L } - a) � .. a) � ! IL % ( __ I q^ i ! _ z&% z� m xX" / Story Mill Park tE Transportation cekant«r. Traffic Impact Study Page a 268 «� In O E 3 0 U U � N N E ~ ~ F ¢ a 0 LL VJHry�)Rx,.LA�1C h 04 ^� n O , ''+^•' v,,n,naa ron vJ F 3 y cn E v� 1 CO O ¢ W N > L 2 � m � n C G QSAP F,,,.e AvnUie = �— LO M I - Pa ulw A101S trf rangy[r.o�, (A uJ fA fm Y W f7 to Ev y O O C7 N a tm u m m C Ip m�; p sso»yepS W cc 'Pa IIIW tiolS Q•—� BAVesnoa C y sea»�+e11S jo OWS Peso OJd l] In �Ip� v N 1 t rIM �� 1�� !� C N pro to A O��.� N eq (D N 4 ^ C, f0 LSC Transportation Consultants,Inc. Story Mill Park Page 16 Traffic Impact Study 269 / ! } k \ � \_Star_ * 9 \ ! 0 � #� b % w 2 ! \ > § 5/ \ , 2 ! E « { g ' £ 'x * ! w k $ ! p ±. *� ��® - / �x / or } ! ,• ; Story Mill Park LSc Transportation cmGeKI. Traffic Impact Study Page 2 270 This page left intentionally blank. LSC Transportation Consultants,Inc. Story Mill Park Page 18 Traffic Impact Study 271 Chapter 4 LEVEL OF SERVICE DESCRIPTION Traffic operations at the study intersections are assessed in terms of Level of Service (LOS)and delay. LOS is a concept that was developed by transportation engineers to quantify the level of operation of intersections and roadways (Highway Capacity Manual, Transportation Research Board, 2010). LOS measures are classified in grades "A" through "F," indicating the range of operation. LOS "A" signifies the best level of operation, while "F" represents the worst. A detailed description of LOS criteria is provided in Appendix B. For signalized intersections, LOS is primarily measured in terms of average delay per vehicle entering the intersection. LOS at unsignalized intersections is quantified in terms of delay per vehicle for each movement. Unsignalized intersection LOS is based upon the theory of gap acceptance for side-street stop sign-controlled approaches, while signalized intersection LOS is based upon the assessment of volume-to-capacity ratios and control delay. Roundabout LOS is based upon the theory of gap acceptance for the traffic entering the roundabout, and an assessment of the conflicting circulating flow. LEVEL OF SERVICE STANDARDS The Level of Service (LOS) standard set forth in the Bozeman Code (Section 38.24.060.B) is as follows: `All arterial and collector streets and intersections with arterial and collector streets shall operate at a minimum level of service "C" unless specifically exempted by this subsection. Level of service (LOS) values shall be determined by using the methods defined by the most recent edition of the Highway Capacity Manual.A development shall be approved only if the LOS requirements are met in the design year, which shall be a minimum of 15 years following the development application review of construction of mitigation measures if mitigation measures are required to maintain LOS. Intersections shall have a minimum acceptable LOS of"C"for the intersection as a whole. a. Exception:If an intersection within the area required to be studied by section 38. 41.060.A.12 does not meet LOS "C"and the intersection has been fully constructed to its maximum lane and turning movement capacity, then an LOS of less than "C" is acceptable. b. Exception: The review authority may accept and LOS of less than "C"at a specific intersection if 1) A variance to allow a lesser LOS was approved not more than two years prior to the date an application for development being reviewed is determined to be adequate for review; 2) The request was made in writing with the application; and 3) The circumstances are in the professional judgment of the review authority substantially the same as when the variance was granted." Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 19 272 ANALYSIS METHODOLOGY The LOS at the study intersections is evaluated for the peak hours by utilizing the Synchro software (Version 8.0, Trafficware), based upon the procedures presented in the 2010 Highway Capacity Manual(Federal Highways Administration, 2010). The Synchro output and calculations are provided in Appendix C for further reference. The roadway LOS evaluation is based on methodology and lookup tables provided by the Florida Department of Transportation. FDOT methodologies are determined to be most appropriate for this area, as the methodologies available using the HCM 2010 and HCS would not be applicable to the characteristics of the study roadways. The ADT lookup tables are contained in Appendix D. LEVEL OF SERVICE ANALYSIS Intersection LOS Intersections in the project area were evaluated to determine existing operational conditions for weekday peak-hour conditions. Table 3 summarizes the results of the LOS analysis for Year 2016 conditions. As shown, all study intersections currently operate at an acceptable LOS C or better during the AM and PM peak hours. With implementation of the proposed project in 2016, some intersections would degrade by one level during the AM peak hour, although the LOS at all study intersections would remain at an acceptable LOS C or better during this period. In the PM peak hour, the following two intersections would degrade from LOS C to LOS D: • Bridger Drive/Bridger Center Drive/ Site Access • Bridger Drive/Story Mill Road TABLE 3: Story Mill Park TIA -Intersection LOS Without Project With Story Mill Park Delay Delay Intersection (sec/veh) LOS (sec/veh) LOS AM Bridger Dr/ Rouse Ave/Griffin Ddve 7.4 A 7.5 A Bridger Dr/ Bddger Center Dr/ site access 12.2 B 17.2 C Bridger Dr/ Birdie Dr 10.5 B 15.6 C Bridger Dr/ Story Mill Rd 15.9 C 16.7 C Story Mill Rd/Griffin Dr 9.2 A 9.2 A PM Bridger Dr/ Rouse Ave/ GdfBn Drive' 7.9 A 8.0 A Bddger Dr/ Bddger Center Dr/ site access 20.4 C 26.2 D Bddger Dr/ Birdie Dr 11.4 B 21.3 C Bddger Dr/ Story Mill Rd 22.7 C 25.2 D Story Mill Rd/Griffin Dr 9.0 A 9.0 A Bold indicates that LOS standard has been exceeded. Note: All intersections are side-street stop-controlled,unless otherwise noted. Note: Delay and LOS are based on most constrained approach for side-street stop-controlled intersections. Note 1: This intersection is signalized. Delay and LOS are reported for the intersection as a w hole. Source: LSC Transportation Consultants,Inc. Story Mill TIA.xlsx LSC Transportation Consultants,Inc. Story Mill Park Page 20 Traffic Impact Study 273 Note that the Bridger Drive /Bridger Center Drive intersection only exceeds the LOS C standard by approximately 1.2 seconds per vehicle, and the Bridger Drive/ Story Mill Road intersection only marginally exceeds the LOS C standard (by 0.2 seconds per vehicle). Although the average delays would increase at the remaining study intersections, they would operate at LOS C or better during the PM peak hour with the project. Roadway LOS The roadway LOS analysis is summarized in Table 4.As shown, all study roadway segments currently operate at an acceptable LOS B, except the segment of Rouse Avenue south of Griffin Drive,which operates at an acceptable LOS C. Implementation of the proposed project in 2016 is not expected to degrade the LOS on any study roadway segment,with the exception of Griffin Drive west of Rouse Avenue,which would degrade from an acceptable LOS B to an acceptable LOS C. As such, no roadway LOS deficiencies are identified with the proposed project. Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 21 274 2$§ u M _ M = o M MtL \ 7 k� ƒ 2 M 00 P- w a ` «� ��K ! /§ < n In ) � { / u in _ M M M M CO 9\\ / � w \ ' m / k 2 � 7 a — — \ § § k U.( k k \ k k k } \ k t_ c f f ] ] f a • 2 § < < < < < \ ) ) \k k \ \ / / / § k ) 8LL ° ƒ ) ) ) ) C § , o A 3 § /� � ] 0 \ \ / $ . c % ) ) f ) § f ] A o o ; « _ ( A $ 2 E | CM IM J M � \ k B ) 3 n � ] k ) k a _ co Q. 2 2 ƒ § \ \ | < = A A § A § 2 ) A r 0 ) ) / / / § 3 G a / LSC Transportationcekants,r. Story Mill Park Page£ Traffic Impact Study 275 Chapter 5 TRAFFIC IMPACTS, RECOMMENDATIONS AND CONCLUSIONS The following potential areas of traffic impacts are considered in this section: • Impact on Traffic Volumes • Intersection Level of Service • Signal Warrant Analysis • Roadway Level of Service • Analysis of the Need for New Turn Lanes Potential mitigation measures are discussed, and recommendations are made. Finally, the conclusions of this study are summarized. IMPACT ON TRAFFIC VOLUMES The project impact on total intersection traffic volumes during the AM and PM peak hours is shown in Table 5. The largest impact occurs at the Bridger Drive/Bridger Center Drive/Site Access intersection, where the total traffic volumes would increase by approximately 38 trips (or 5.6 percent) in the AM peak hour and 95 trips (or 10.2 percent) in the PM peak hour.Note that the project has a minimal impact on the total traffic volumes through the Bridger Drive/ Story Mill Road intersection,with an increase of less than 2.0 percent. TABLE 5: Story Mill Park-Traffic Volume Impacts Total Intersection Entering Volume Percent Increase in Traffic Due to Existing Project Generated Project Intersection AM PM Sum AM PM Sum AM PM Sum Bridger Dr/Rouse Aye/Griffin Drive 1,001 1,286 2,287 34 82 116 3.4% 6.4% 5.1% Bridger Dr/Bridger Center Dr/site access 683 928 1,611 38 95 133 5.6% 10.2% 8.3% Bridger Dr Birdie Dr 612 853 1,465 13 28 41 2.1% 3.3% 2.8% Bridger Dr/Story Mill Rd 677 906 1.583 5 15 20 0.7% 1.7% 1.3% Story Mill Rd/Griffin Dr 164 161 325 4 9 13 2.4% 5.6% 4.0% Daily Traffic Volumes(ADT) Percent Increase in Project ADTDueto Roadway Existing Generated Project Rouse Avenue,South of Griffin Drive 11,260 394 3.5% Bridger Drive,Between Griffin Drive and Bridger Center Drive 8,140 528 6.5% Bridger Drive,Between Bridger Center Drive and Birdie Drive 7,990 279 3.5% Bridger Drive,Between Birdie Drive and Story Mill Road 7,100 99 1.4% Bridger Drive,East of Story Mill Road 5,230 32 0.6% Griffin Drive,West of Rouse Avenue/Bridger Ddve 9,180 134 1.5% Story Mill Road,North of Bridger Drive 1,640 6 0.4% Story Mill Road,South of Bridger Drive 750 65 8.7% Source.LSC Transportation Consultants,Inc Story Mill TlAxlsx The project impact on roadway daily traffic volumes (ADT) is also estimated. As shown in the lower portion of the table, the biggest increase in ADT occurs on the segment of Bridger Drive Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 23 276 between Griffin Drive/Rouse Avenue and Bridger Center Drive, with an increase of approximately 528 ADT(or a 6.5 percent increase). Story Mill Road immediately south of Bridger Drive would experience an increase of approximately 65 ADT(or an 8.7 percent increase). During the AM peak hour, the project is estimated to increase the total two-way traffic volume on Story Mill Road immediately south of Bridger Drive by approximately 4 one-way trips, or one trip every 15 minutes, on average. During the PM peak hour, the project would add approximately 9 one-way trips,which equates to less than one trip every 6 minutes, on average. Although the project proposes improvements to a portion of East Griffin Drive in order to enhance conditions for non-auto modes, the project is expected to have a minimal impact on traffic volumes along this roadway. INTERSECTION LOS IMPACTS Implementation of the proposed project would cause the following two intersections to degrade from LOS C to LOS D during the PM peak hour: • Bridger Drive/Bridger Center Drive/ Site Access • Bridger Drive/ Story Mill Road Potential intersection LOS mitigation measures are discussed below.No intersection LOS deficiencies are expected during the AM peak hour. Bridger Drive/Bridger Center Drive/Site Access Due to the proposed project, the average delay increases by approximately 5.8 seconds on the worst approach. Although provision of a separate right-turn lane on the site driveway approach would improve the LOS for drivers turning right onto Bridger Drive, this would not improve the LOS to an acceptable level. Provision of a central two-way left-turn lane (TWLTL) along Bridger Drive west of the intersection, which would allow two-stage left-turn movements to be made from the site driveway,would improve the LOS to an acceptable LOS C under `existing plus project' peak-hour conditions. This turn lane improvement is a planned improvement by MDT(along with new sidewalks and other improvements). Bridger Drive/Story Mill Road Due to the proposed project, the average delay increases by approximately 2.5 seconds on the worst approach. Provision of a separate left-turn lane on the northbound Story Mill Road approach would improve the LOS to an acceptable LOS C or better under `existing plus project' peak-hour conditions. This improvement would require widening the median of Story Mill Road within the vicinity of Bridger Drive, which is consistent with the City's long-term vision of a 3- lane cross-section along Story Mill Road. Alternatively, provision of a separate right-turn lane on the northbound Story Mill Road approach would improve the LOS to an acceptable LOS C or better with the project; however,this improvement may not be desirable due to right-of-way constraints. LSC Transportation Consultants,Inc. Story Mill Park Page 24 Traffic Impact Study 277 Year 2018 Intersection LOS The MDT improvements along Bridger Drive are expected to be completed by 2018. In order to estimate Year 2018 intersection volumes, ADT forecasts for Bridger Drive and Story Mill Road were obtained from the traffic model that was recently updated as a part of the City's Transportation Plan Update project. Based upon a review of the model's 2014 and 2040 traffic volumes, the average annual growth rates along Bridger Drive and Story Mill Road in the study area are estimated to be approximately 1.3 percent and 3.3 percent, respectively. Applying these growth rates to the 2016 PM peak-hour intersection volumes yields the `2018 no project' PM peak-hour volumes shown in Table 6. Adding the project-generated volumes to those volumes yields the `2018 with project' volumes shown in the lower portion of the table.Note that traffic volumes are not developed for the 2018 AM peak hour, as PM peak-hour conditions represent the worst case. Intersection LOS was evaluated under 2018 conditions at the two intersections expected to operate at LOS D in 2016. Assuming the MDT improvements are complete, the results indicate that the Bridger Drive/Story Mill Road intersection would continue to operate at LOS D. However, widening the Story Mill Road approaches to provide exclusive left-turn lanes would improve the LOS to an acceptable LOS C with the Story Mill Park Project in 2018. SIGNAL WARRANT ANALYSIS The peak-hour traffic volumes were reviewed against the signal warrant criteria presented in the Manual on Uniform Traffic Control Devices(MUTCD, U.S. Department of Transportation, Federal Highway Administration). The traffic volumes with the proposed project in 2016 do not meet the criteria at any of the unsignalized study intersections during the AM and PM peak hours. The criteria is also not met in 2018. ROADWAY LOS IMPACTS As all study roadway segments would operate at an acceptable LOS C or better with the proposed project in 2016, no roadway LOS deficiencies are identified. ANALYSIS OF THE NEED FOR NEW TURN LANES The need for left- and right-turn lanes along a main roadway is evaluated based on the guidelines specified by National Cooperative Highway Research Program (NCHRP) Report 457 "Evaluating Intersection Improvements: An Engineering Study Guide" (Transportation Research Board, 2001). The turn lane warrant criteria charts are included in Appendix E. The need for new turn lanes is evaluated only for side-street stop-controlled intersections, as the need for turn lanes at signalized and roundabout-controlled intersections is determined by level of service. Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 25 278 2 < § 7g § / a) _ _ CMQo « Qo - E 2 k / k ) \ \ \ \ \ \ � C §_ 00 � @ _ & & - oa 3 © @ - � / \ § \ \ \ \ � ca D a@ / » Q § -j 0 & 2 w 7 mma mma � k 2 / / ooq ooR � k Z - \ any CD E ƒ 0402 CO Q Q \ 00 .0 oom oom \ C p m � % f r- oe mI2 / i � M ` � w Cn j 3 66 § Via § 0 tim 5 /§ { Cn / ia § ) ± mG / LLA t50 � \ kk \ ) zoo \ & § § 0) � fff f7f Zq ± 3m k333 G LSC Transportation cema«I. Story Mill Park Page A Traffic Impact Study 279 Left-Turn Lane Warrant Analysis Left-turn lane volume warrants are defined by volume thresholds of opposing traffic versus advancing traffic, as well as the percentage of left-turns on the advancing approach. The warrant chart is attached. The need for new eastbound and westbound left-turn lanes along Bridger Drive was evaluated at the intersections of: • Bridger Center Drive/Site Access • Birdie Drive/Proposed Site Access • Story Mill Road The left-turn lane warrant analysis determined that the following left-turn lanes are warranted: • Eastbound at Birdie Drive both with and without the proposed Story Mill Park project • Eastbound at Story Mill Road both with and without the proposed Story Mill Park project Note that both of these left-turns are warranted during the PM peak hour only.No other left-turn lanes are warranted within the study area. Right-Turn Lane Warrant Anal Right-turn lane warrants are based on a graphical curve of right-turning volumes versus total traffic in the travel lane. The warrant chart is attached. The peak-hour traffic volumes do not meet the right-turn lane warrant at any of the unsignalized study intersections under either of the study scenarios. RECOMMENDATIONS The following recommendations are made regarding the proposed project: • If all approaches on the unsignalized intersection of Bridger Drive/Bridger Center Drive / Site Access are required to operate at LOS C or better under Year 2016 conditions with the proposed project, it is recommended that a central two-way left-turn lane (TWLTL) be constructed along Bridger Drive west of the intersection. This turn lane improvement (along with other improvements, including new sidewalks), is a planned improvement by MDT. With this improvement, an acceptable LOS C would also be provided in 2018. • Provision of a separate left-turn lane on the northbound Story Mill Road approach to Bridger Drive would improve the LOS at this intersection to an acceptable LOS C or better under `existing plus project' peak-hour conditions. This improvement would require widening the median of Story Mill Road within the vicinity of Bridger Drive, which is consistent with the City's long-term vision of a 3-lane cross-section along Story Mill Road. Alternatively, provision of a separate right-turn lane on the northbound Story Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 27 280 Mill Road approach would improve the LOS to an acceptable LOS C or better with the project; however, this improvement may not be desired due to right-of-way constraints. Assuming the MDT improvements are completed in 2018, the Bridger Drive/ Story Mill Road intersection would continue to operate at LOS D. However, widening the Story Mill Road approaches to provide exclusive left-turn lanes would improve the LOS to an acceptable LOS C with the Story Mill Park Project in 2018. • The turn lane analysis determined that an eastbound left-turn lane is warranted at the Bridger Drive/Birdie Drive intersection and an eastbound left-turn lane is warranted at the Bridger Drive/Story Mill Road intersection. These left-turn lanes are shown to be warranted with or without the proposed project. • It is noted that there is potential for local transit service to be provided in the future, but it is determined that it would not materially affect the findings and conclusions of this analysis. CONCLUSIONS • The proposed Story Mill Community Park is estimated to generate a total of approximately 638 daily one-way vehicle trips on a typical weekday without an event scheduled. The project is estimated to generate 41 vehicle trips (28 entering and 13 exiting) during the AM peak hour of the design day, and 99 vehicle trips (55 entering and 44 exiting) during the PM peak hour. • The project would result in an increase in traffic at any given study intersection of up to 95 peak-hour trips (through the Bridger Drive/Bridger Center Drive / Site Access intersection). The project would have a minimal impact on the total traffic volumes through the Bridger Drive/ Story Mill Road intersection (up to 15 peak-hour trips). • The project would increase the ADT on any given roadway segment by up to 528, which occurs along Bridger Drive between Griffin Drive/Rouse Avenue and Bridger Center Drive. The project would increase the ADT on Story Mill Road at a point immediately south of Bridger Drive by approximately 65 ADT. During the AM peak hour, the project is estimated to increase the total two-way traffic volume on Story Mill Road immediately south of Bridger Drive by approximately 4 one-way trips, or one trip every 15 minutes, on average. During the PM peak hour, the project would add approximately 9 one-way trips, which equates to less than one trip every 6 minutes, on average. The project is expected to have a minimal impact on traffic volumes along East Griffin Drive. • All study intersections currently operate at an acceptable LOS C or better during the AM and PM peak hours. With implementation of the proposed project in 2016, some intersections would degrade by one level during the AM peak hour, although the LOS at all study intersections would remain at an acceptable LOS C or better during this period. In the PM peak hour, the following two intersections would degrade from LOS C to LOS D: LSC Transportation Consultants,Inc. Story Mill Park Page 28 Traffic Impact Study 281 o Bridger Drive/Bridger Center Drive/ Site Access o Bridger Drive/ Story Mill Road If all approaches on the unsignalized intersection of Bridger Drive/Bridger Center Drive /Site Access are required to operate at LOS C or better under Year 2016 conditions with the proposed project, it is recommended that a central two-way left-turn lane (TWLTL) be constructed along Bridger Drive west of the intersection. This turn lane improvement (along with other improvements, including new sidewalks), is a planned improvement by MDT. With this improvement, an acceptable LOS C would also be provided in the Year 2018. At the Bridger Drive/Story Mill Road intersection, provision of a separate left-turn lane on the northbound Story Mill Road approach to Bridger Drive would improve the LOS at this intersection to an acceptable LOS C with the proposed project. This improvement would require widening the median of Story Mill Road within the vicinity of Bridger Drive, which is consistent with the City's long-term vision of a 3-lane cross-section along Story Mill Road. Alternatively, provision of a separate right-turn lane on the northbound Story Mill Road approach would improve the LOS to an acceptable LOS C or better with the project; however,this improvement may not be desired due to right-of-way constraints. Assuming the MDT improvements are completed in 2018, the Bridger Drive/ Story Mill Road intersection would continue to operate at LOS D. However,widening the Story Mill Road approaches to provide exclusive left-turn lanes would improve the LOS to an acceptable LOS C with the Story Mill Park Project in 2018. • The traffic volumes with the proposed project in 2016 do not meet the peak hour traffic signal warrant criteria at any unsignalized study intersections during the AM and PM peak hours. The warrant criteria is also not met in 2018. • All study roadway segments would operate at an acceptable LOS C or better with the proposed project in 2016; no roadway LOS deficiencies are identified. • The turn lane warrant analysis has determined left turn lanes are warranted for the following intersections: eastbound at the Bridger Drive/Birdie Drive intersection; and eastbound at the Bridger Drive/Story Mill Road intersection. These left-turn lanes, which are warranted with or without the proposed project, are planned to be installed as a part of the upcoming MDT project.No right-turn lanes are warranted at any of the unsignalized study intersections. • There is potential for local transit service to be provided in the future, but it is determined that it would not materially affect the findings and conclusions of this analysis. Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 29 282 This page left intentionally blank. LSC Transportation Consultants,Inc. Story Mill Park Page 30 Traffic Impact Study 283