Loading...
The URL can be used to link to this page
Your browser does not support the video tag.
Home
My WebLink
About
16 - Traffic Impact Study - Story Mill Community Park
�ogB02Lc+ THE CITY OF BOZEMAN 9 20 E. OLIVE • P.O. BOX 1230 BOZEMAN, MONTANA 59771-1230 t 'k ENGINEERING DEPARTMENT eiy?,J�gOtti� PHONE: (406) 582-2280 • FAX: (406) 582-2263 o 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 fT,r4TE UNIVERSITY GATEWAY TO YELLOWSTONE PARK . , .I .I I . I, THE CITY OF BOZEMAN 20 E. OLIVE • P.O. BOX 1230 V x BOZEMAN, MONTANA 5977 1-1 230 QQ ENGINEERING DEPARTMENT TABLE OF CONTENTS CO. SECTION PAGE 1 INTRODUCTION ...............................................................................................................I ProjectDescription......................... ............................................................................I Scopeof Study...............................................................................................................2 2 EXISTING CONDITIONS..................................................................................................3 RoadwayCharacteristics................................................................................................3 Existing (2016) Traffic Volurnes...................................................................................5 3 PROPOSED CONDITIONS................................................................................................9 ProjectDescription.........................................................................................................9 Trip Generation, Distribution, and Assignment.............................................................9 4 LEVEL OF SERVICE.......................................................................................................19 Description...................................................................................................................19 Levelof Service Standards ..........................................................................................19 AnalysisMethodology.................................................................................................20 Levelof Service Analysis..... .. . ........................................................................20 5 TRAFFIC IMPACTS, RECOMMENDATIONS AND CONCLUSIONS .......................23 Impacton Traffic Volumes..........................................................................................23 IntersectionLOS Impacts ............................................................................................24 SignalWarrant Analysis..............................................................................................25 RoadwayLOS Impacts -...........I..................................................................................25 Analysis of the Need for New Turn Lanes ..................................................................25 Recommendations........................................................................................................27 Conclusions..................................................................................................................28 APPENDIXA: TRAFFIC COUNTS APPENDIX B: LEVEL OF SERVICE 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 Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page i HOME OF MONTANA L��TE UNIVERSITY GATEWAY TO YELL STONE PARK r .. t i :,�. 13 THE CITY OF BOZEMAN 20 E. OLIVE • P.O. BOX 1230 V x BOZEMAN, MONTANA 59771-1 230 OCy M111 Pack—Roadway I NEERING DEPARTMENT................................. 22 C � P F N ( 06) 5 2-228 • FAX: (406) 582-2263 p� Story Mill Park—TratticVolumeimpacts........................................................................23 6 Story Mill Park—Year 2018 PM Peak-Hour Intersection Traffic Volumes.....................26 LIST OF FIGURES FIGURE PAGE I 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 ff�kTE UNIVERSITY GATEWAY TO YELLOWSTONE PARK '; � , 1 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 I 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 1-90 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 / k � e $ | \ - m- ® c = J { ( C § / 4 ] e 0 ; f o to CO > 6 U ~ ® ^ o i N .. %> Q _ k,16 m \} \ § X \ ® A % \ iw U D.- LU ! % CU ` LL { ., \ k / o _O � U) k ? � � i ( � i § k m - m^AJOI~ -AL § / � 0 (D k s coo- 0 a:� � § § Io ) @ \ � �( §a o m�O § as ° _me Rf IU1-4s© 't mBIG «_m � _Oa m m mG ) mm* \ 4 f � m 0 \> LSC Transportationcmkant«I. Story Mill Park Page AcIpaas& 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. r 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 \ _ \ \ { k k . 0 § j � ( t f @ K / \ I . . / \ k /_w ) f t � / 'A . . . . m { � m 2 x \\ 7 q /CU \ LE % \ � ( { ! � ? { R - � ! ( ! � = m mom® _ _ s .. � zal « - - \ z ■ _�« ■ 0 tM � � �\ � / �� �a �- r m^ k ©mVs { 4 811348 � dm mG ) — }� �§ ( ! �f� A / \ � /e� f /� w� % \ LSC TransportationConsultants,Inc. Story Mill Park Page Aafific Impact 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 � ) } t_mL . | ___ / . \ - % 2 E ® e ƒ . \ 0 a a • ` \ $ E M {CM 7 � 2 lip ! k 2 % ! \ � i ! _ « . � . _, x" LSr Transportation Consultants,Inc. Story Mill Park 778 Traffic Impact Study 261 Chapter 3 PROPOSED CONDITIONS i 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 co 0 N q w m N K U = Q m N m I O m N Lo 0 0 0 lo m Ln N m ; m a L= n I O O m �2 N 0 0 R y O O O O O a p Ol V �2 0 0 0 0 N V m m --t N ,SrevX2 g n u o � t 2 d m r v I o o m o o o 0 o Ln o 0 o 0 0 mEL 'c QIQ o Q C L° 10 m O O O O O N N m m N L V G O F � ` V tl n n n ?. N m m m � N 0 0 0 LA O a Q N I N m V h v m t0 N N O m Q 6 S D gam _ o � o000000 0000 ' c no z a) `c � Q o rn o q °° Lq n o o I v Lon v uo N I i cc p O o o .- o 0 0 0 0 o 0 0 m Ln l o o m rn Ln o 0 o I o h a o m cm o m o L� o 0 0 0 .. a o 00000000 0000 e N d O O o m Ln Ln Ln 0 0 O O O O 6 O O r✓ c l o o m o o o o 00 0 I o 0 0 0 q c an d � o 0 0 0 0 0 0 c m t omLno00oo aLov n wYo � 88 O j 0 I m C? O O O O O I O N O N E °- n a u Y o ff o o o o 0 0 0 0 0 0 0 0 3 1 g a a i r. 5 n ID o o 0 o m o 0 o 0 o I o o D m I 0 o m o 0 0 0 0 0 � a o 0 0 0 0 0 0 0 0 0 0 0 0 ° Yo -C 2 O O o m m o 0 0 o o < Ln v Lo ~ Q C O I of m 0 0 0 0 0 I O N fJ 0000 C O 0 0 0 0 0 0 0 0 0 0 0 0 6 o Z• � }. lq ^q � W b a ss 3 9 a V •Jo-D U T n o 0 0 0 0 0 0 0 0 0 o o c¢ Y n- 'Lp m t o La m m o 0 o I m o m o 96 b P tq P C o ti a ❑ V N m Co N N N N O N O N Y G Y p p p o U i 9 c r n XAI w N LL fU N m m m m m N Y T n a n n a n n r o u o " o Q aE r r r r c c ¢ to rn W o i8 5 o E m m m m m m m c o - d F^ 3 Lo o waaaaaaa a V m ] n s yg t W L g rc c n N r o N o o 0 o m o o °o n Lu S$ n g x Q «p v Q t°D N N m m N O N m �- µlv rEO QaQaQaQaQ Q Q Q o ov' T� i£ �� 3gaa � a U zzz 'z o a � vv a � aaaQaaaaa J o �2 Z Z Z Z Z Z Z Z Z Z Z oL U c p 5 6 m a °• 'v µIL1 7 pp o a O ; LU n a N o Fj qE 9 t ° O m y F m p £' o M m o '° E y o O N Ln 3 R 7 L O G w m W A m M N � F- a Q ' c c m n,y q y a- °: v o mw m j m H S «�+ L161. YosoSc u � n C U m n Ln eE m E O ^+ o o m $ e m �. o n 2 n ? u to L'L « c o m �0 E c £ e v "> @ W m w�'.� o f a�i u y am` U L��a Wgy�r, 0 J n E u U :5 Ln � (J N _ Y U Ln3 t �f dia�`v'Li FA O � N O m C J NC Y Q N N E E O m U C m lT 1p N n C 5 N t 1 v N 0 n 0 ry m o o U a ❑ a Q (7 w o O n E w w 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 I 1 264 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 B ridger 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. Page 13 Traffic Impact Study 266 O C Ul N E O 7 7 � > U U N (0 O g N Mabfn 54v L.m t 1 4,p �Q '�") O U FA (Q yX�w�NM LaM E- LO k N ^ �F p _ -...,, C ^� O I.CL C a vd� w � Q eKrw•ix��n � � � a� m c� �.0 •o � a` s m a n ` M h � Oo — 'Pa II!"NoIS tYRRra'Rwe 2 a. o p`` it O,t i on� oO ❑�Nm GJ 1O m '= O °� sseo�y allg N m 'ony osnoa M sser�y a�lg �Q aiPnB Pasooa i d 'P2t II W NWS j o o 0 O N m) O rp 1 1 o C O o CO o 1y 04 .1 LSC Transportation Consultants,Inc. Pa e 14 Slory Mill Park S Traffic Impact Study 267 K VI S C7 O u] O V) 14 R. -I Cn O O yypryw�R«f�azle � °hS w �t� r � VnI1.MaC.hr[ _� r3 0 C 0 LU U I— N >, ggy,ernre � 5 LO 'm :3 a '° a ii m m c v I N 9 t d yrnnv�btl v✓+/ �,p�rF Arn>Ac pylrtla�Rvc �� I /' ire Attes' p / d I/ / Story Mill Park LSC Transportation Consultants,Inc. Traffic Impact Study Page 15 268 k vx U e L o N a) E z > > > 0 m m U U � ' F F F Q a t � L MaNcn Oar Larr - ^m 1..L Ln 3 0 U y E a CO U LL m n a v 0 , O �1 Z J�u[I�e9HJ C • l� �\ Q � O C � f— rn allo tY PH II!W Lois r n CO N p> Q r t GI Q Q OD NCD O V M a N m O E�O O m r , a O t�k M ._" Q m ssaooyaYig fA m .� > - 'enV esnoa W ,� o�e��euNi ss�y el! S Ap ajPjtg pas000�d 0 Pa II!W tiolS N k --� rnm _►F O p m p o 0�� N uN'1 N��► t+1 1 (� v m N ap m GD� m �•a V Oi N� V N °1 VNM`�Jp N � �cv M O O O 0 N LSC Transportation Consultants,Inc. Story Mill Park Page 16 Traffic Impact Study 269 ! / & � \ ° ! . } � ! � _ \ Uj \ w 'a § ] � k ! . �¥ �, : • z® Story tea LSC Transportationcmkn&I. 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 Drive 7.4 A 7.5 A Bridger Dr/ Bridger 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/ Griffin Drive 7.9 A 8.0 A Bridger Dr/ Bridger Center Dr/site access 20.4 C 26.2 D Bridger Dr/ Birdie Dr 11.4 B 21.3 C Bridger 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 l: This intersection is signalized. Delay and LOS are reported for the intersection as a whole. 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 $\§ o LD _ = m o = _ \ § �2 £ < $2 \ a a < u in a ` g5 - ƒ12 m § [ e % § o M _ M _ _ _ in w u78 e-# ' / < } / ' 3 \ k 7 2 a a 7 f 7 7 7 ) k k J \ \ \ \ \ \ ) k LL�k k \ \ \ \ k � / § p # 7 M. _ § \ \ k \ < < } ( f \ / /to \ \ \ ) ) o (L M LL a- (1- § L) \ � ] 0 \ \ \ } k ) \ ) % f A c o g < A a) � a)G 3 en .2 J ] M \ B B ) { \ A A 3 3 3 COk ] 3 a _ � k W B \ ) ) J < o A A c A § § k It J } M } I a m m k LSC Transportationc_% Inc. Story Mill Park Page£ TfficImpact 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 Tralfic Due to Exisung Project Generated Project Intersection Ai,1 PM Sum AM PM Sum AM PM Sum Bridger Dr/Rouse Ave/Griffin Dd%e 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 Drive 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 TIA.xlsx 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 k00 \ kk ) e � / Qom Qo - _ 2 \ / gG § BSm mm04 nn � \ \ Hof = - � � @ � & 5 Boa 7 = @ � E ) / m@ \ gGg � � � « « 00 ca � � CDag / ag / c -i 0 k mm / mm ) � E � 2 2 / ƒ ooq oo 04 R 5 � A 2 \ ens anL _ $ 2 r- m � � m 2 0 2 CO 00 / ƒ oom oog \ o 0 % C44 Z ( % a) woa mr2 \ k ( C § j } ) 2 I § _0 § 0 oa = o ± § 0 CO CL - /§ [ ) 'a / 3a § ) 3I .2 / � 2 (L kkk § m k / kkk § kkk M .12 § 78333 \ 33CO / LSC Transportationcekant«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 Analysis 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