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HomeMy WebLinkAbout01 - Traffic Impact Study - Baxter Meadows Development Traffic Impact Study Baxter Meadows Development Bozeman, Montana Robert Peccia & Associates October, 2001 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman,Montana October, 2001 I. GENERAL PROJECT DESCRIPTION 1 II. EXISTING CONDITIONS 1 Baxter Lane 1 Davis Lane 1 Harper Puckett Road 3 Additional Developments 3 Traffic Counts 3 Level of Service 3 III. PROPOSED DEVELOPMENT 4 Proposed Roadway Layout 6 Pedestrian and Bicycle Facilities 8 Development Timeframe 9 IV. TRIP GENERATION AND ASSIGNMENT 9 V. TRIP DISTRIBUTION 12 VI. TRAFFIC IMPACTS WITHIN THE DEVELOPMENT 13 VII. TRAFFIC IMPACTS OUTSIDE OF THE DEVELOPMENT 14 Traffic Impacts From Phases One and Two 17 Traffic Impacts From Phase Three 18 Traffic Impacts From Phase Four 19 Traffic Impacts From Phases Five and Six 19 Vill. IMPACT SUMMARY 21 IX. RECOMMENDATIONS 21 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman,Montana October, 2001 I. GENERAL PROJECT DESCRIPTION This study analyzes and documents the potential traffic impacts resulting from a proposed mixed-use residential and commercial development in Bozeman, Montana. The 460 acre site is located northwest of the Bozeman City Limits on Baxter Lane between Davis Road and Harper Puckett Road (Cottonwood Road) and between Oak Street and Deadmans Gulch. The developers plan to construct single-family homes, townhouses, a mixed-use commercial area, an elementary school, and a park. II. EXISTING CONDITIONS The site is currently utilized as farm and ranch land. The site is mostly flat with some rolling hills. The site is primarily accessed by Baxter Lane, which is a two lane paved road that cuts through the middle of the property from east to west. Baxter Lane connects from North 19th, one mile east of the property, passes through the property and continues west through the valley to Jackrabbit Lane. Davis Road and Harper Puckett Road (both unpaved roads)begin at Baxter Lane and proceed north to connect with Valley Center Road. Flanders Mill Road is also unpaved and proceeds South from Baxter Lane and connects with Durston Road. See FIGURE 1 for a location map of the proposed development. Baxter Lane Baxter Lane approaches the development from an intersection with North 19th, one mile east of the property. This paved road is approximately 2,4-feet wide, with two twelve-foot lanes. The road is old, has no shoulder, and shows evidence of a large amount of cracking and patchwork. This road travels straight through the proposed development and changes to a gravel surface one mile west of the site. Traffic counts performed by Robert Peccia&Associates (RPA) in July 2000 indicate that this road has an average daily traffic (ADT) volume of approximately 460 vehicles per day (VPD) between Davis Road and Harper Puckett Road. A traffic signal has been recently installed at the intersection of Baxter Lane and 191h Avenue. Davis Road Davis Road begins at Baxter Lane and travels north. The Road has a gravel surface and is 24-feet wide.There is a residential area on the eastern side of the road with approximately ten homes. These homes become increasingly sparse as the distance from Baxter Lane increases. The road connects to Valley Center Road approximately one mile north of the Baxter Lane intersection. Traffic counts indicated that this road has an ADT volume of approximately 110 VPD. This traffic count was taken north of the residential area and indicates only the traffic that passes through that location. 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The road connects to Valley Center Road approximately 2.5 miles north of Baxter Lane. Traffic counts show the road currently has an ADT of 280 VPD. Harper Puckett Road is controlled by a STOP sign at each end. Additional Developments There are currently two additional developments being proposed in the area. The Harvest Creek development is currently under construction. This development is located to the south of Oak Street and to east of Davis Road. This development would cover 130 acres and consist of 450 residential units. As part of this development, Oak Street would likely be constructed to within 100 yards of Davis Road. The development should be constructed within the next five years. Another proposed development is the Sandan LLC, which is located to the east of Davis Road along Deadmans Gulch. This smaller development (approximately 100 residential units on 35-40 acres) is currently in the planning phase and may or may not be constructed within the next ten years. If the development is constructed it is possible that Deadmans Gulch would be connected to Davis Road. Traffic Counts RPA collected turning movement counts in the fall of 1999 for the intersections on North 19`h Avenue including Baxter Lane, Oak Street, and Durston Road as part of the Greater Bozeman Area Transportation Plan 2001 Update. Traffic volume data was also collected from state and local agencies for roads around the proposed development. This data was used to produce base traffic volume information. Level of Service A level of service (LOS) analysis was conducted using existing traffic volumes at the following intersections: • North 191h Avenue and Valley Center Drive; • North 19`h Avenue and Baxter Lane; • North 19`h Avenue and Oak Street; 3 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman, Montana October,2001 • North 71h Avenue and Oak Street; • North 19`h Avenue and Durston Road; • 19`h Avenue and Main Street; • South 19`h Avenue and College; These intersections were analyzed using turning movement count information collected by RPA in 1999. LOS levels are given letter designations from A to F, whereby LOS A represents the best operating conditions and LOS F the worst or saturated flow conditions. This analysis is intended to determine how well the intersection is currently functioning with respect to variables such as traffic flow and other prevailing conditions. The LOS evaluation was conducted according to the procedures outlined in the Transportation Research Boards' Highway Capacity Manual (HCM) - Special Report 209 and the Highway Capacity Software (HCS) for intersection analysis. From the data, it was determined that some operational deficiencies currently exit at intersections that would be affected by the development. The anticipated area growth patterns from the Greater Bozeman Area Transportation Plan 2001 Update were analyzed to determine future intersection traffic volumes. This information was then used to determine the LOS at the intersections in 2010. TABLE I shows the LOS of intersections studied for this report in 2000 and 2010. TABLE 1 —Level of Service LOS Summary 2001 2001 2010 2010 Intersection AM Peak PM Peak AM Peak PM Peak 19`h &Valley Center fC C C C 19`h &Baxter B B B C 19`h & Oak B C C* C* 71h & Oak C C C C 191h &Durston C F C* D* Main & 191h F _ F C* D* 191h & College E F D* D* *With anticipated intersection improvements III. PROPOSED DEVELOPMENT The proposed development includes a total bounded area of 460 acres. FIGURE 2 shows a preliminary plat of the development. The proposed development site consists of six different phases. The first four phases would consist of constructing residential and commercial areas north of Baxter Lane. These phases would include the construction of residential areas, shops, and businesses. The area would provide services, shopping, and employment for residents of the development and the surrounding area as well as park areas and some light manufacturing. The first four phases would be constructed between 2002 and 2007. Phases five and six be constructed between 2008 and 2010 4 Deadman's Gulch Phase IV v 1 v Hotel m Convention_ rY Cente( � t Y � 1 � Pha sle 111 CU co _ 1 Ph se 11 `a i o � � E LL I Phase 1 Phase 11 Phase VI Baxter Lane a ca a a� m m v 0 200 0 1004 0 �z> Proposed 100-Acre Phase V Regional Park Oak Street Figure 2 Proposed Development Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman, Montana October, 2001 and would include the construction of a large residential area south of Baxter Lane with a local fire station, community center, elementary school, and park areas with game fields. Additional residences a commercial area would also be constructed north of Baxter Lane as part of phase six. The northwest quadrant of the development would consist of widespread upscale houses on 1/3 acre lots, a horse barn, and equestrian facilities. Proposed Roadway Layout Only Baxter Lane,Davis Road, Flanders Mill Road, and Harper Puckett Road currently connect the proposed development property to the existing street grid. The City of Bozeman Planning office was contacted in order to determine when additional roads would likely be connected to the existing street grid. Information from the planning office indicated that in the near future Oak Street should be extended west to Davis Road and connected to the proposed development site. The `Harvest Creek' development is currently in phase three of construction, which should bring Oak Street to within 300 feet of Davis Road within the next two years. Phase Four of this development would connect Oak Street to Davis Road and may be completed by 2005. It is not anticipated that additional roadway connections will be completed prior to the completion date of the Baxter Meadows Development(2010). It is possible that Deadmans Gulch would extend west to connect to the development prior to full build-out in 2010,but this connection is not certain at this time. The construction of Davis Road,Ferguson Road, and Cottonwood Road are expected at some time in the future,but it is not likely that any of these roads would be completed prior to full build-out of the Baxter Meadows development. In addition to the local streets that would provide access to the individual lots within the development, the developer proposes to build five major roads that would serve as the primary access routes to the proposed development; three running east/west and two running north/south. FIGURE 3 shows the proposed road layout. The developer proposes to construct the following roads: • Baxter Lane-From Davis Road to Ferguson Road; • Deadman's Gulch-From Davis Road to Ferguson Road; • Davis Road- From Oak Street to Deadmans Gulch; and • Ferguson Road-From Baxter Lane to Deadman's Gulch. The developer proposes to construct a portion of the ultimate road section on several roads that border the development including Davis Road (Oak north to the Hotel/Convention Center site), Baxter(west of Ferguson Road), and Deadman's Gulch (Davis to Ferguson. In each of these cases the initial road section would include at a minimum two 10-foot travel lanes and two five-foot 6 _I Deadman's Gulch I ± Phase IV let; Sr l� cu . f 46 o t u y; 1 � � iT -o s O U i' i _ c tt • s .rf". N 'L N Phase r Phase I Phase II Ph°ase Vl f Baxter Lane -- �i• i-i-it-i-ii�-i-0-t-�i^1 -il-i-i�-4 •-■ � i N co m co 0 200 0 i rY 100 400 O ' c a` Ultimate Road Section Proposed 100-Acre Phase V ■ ■ ■ ■ ■ ■ ■ 2-Lane Principal Urban Arterial Regional Park ■ ■ ■ ■ ■ ■ ■ 2-Lane Minor Urban Arterial ® 3-Lane Minor Urban Arterial ■ ■ ■ ■ ■ ■ ■ 2-Lane Urban Collector ■ ■ ■ ■ ■ ■ ■ 2-Lane Rural Minor Arterial _ _ _ _ _ Oak Street Residential Access •�---•--�•--•- �-• Commercial Area �— Neighborhood Access �--�_ Commercial/Neighborhood —-- - Gravel Road OModern Roundabout Figure 3 Proposed Street Network Traffic Impact Analysis Baxter Meadows Development Robert Peccia&Associates Bozeman, Montana October, 2001 bicycle lanes. At this point the proposed park located in the southeast quadrant of the section is anticipated to become a county park. If this occurs Gallatin County would be responsible for constructing Oak Street between Davis Road and Ferguson Road and Ferguson Road between Oak Street and Baxter Lane. All roads within the proposed development would be paved. Roads in the northeast and southeast quadrants would have urban cross-sections meeting the urban road standard adopted by the City of Bozeman as part of the Greater Bozeman Area Transportation Plan 2001 Update. The developer plans to dedicate right-of-way for each of these roads. According to the Greater Bozeman Area Transportation Plan 2001 Update (RPA), Oak Street and Harper Puckett are designated as principal arterials, Baxter Lane and Davis Road are designated as minor arterials, and Ferguson Road and Deadmans Gulch are designated as collector streets. The developer plans to dedicate right-of-way that meets or exceeds the road standards adopted by the City of Bozeman as part of the Greater Bozeman Area Transportation Plan 2001 Update (see Exhibit"C")for all roads except cul-de-sacs. In these cases the proposed 54 feet of right-of-way appears appropriate for these short dead-end local roads. The preliminary traffic plan for the development proposes several different street cross-sections for the different areas within the development.FIGURE 3 shows the distribution of the street type and lane configuration within the development and Exhibit"C" (in the pocket at the back of this report) shows the proposed street cross-sections. The developer is proposing 10-foot wide driving lanes on all roads. This is less that the 11-foot lane width called for in the road standards collector and arterial roads. The 10-foot lane widths are proposed by the developer in an effort to produce slower vehicles speeds. Considering the nature of the development the proposed road sections appear to be adequate for the anticipated traffic volumes. The developer is proposing five modern single-lane roundabouts. Four are located on Baxter Lane and one is located on Davis Road. All other intersections within the development would be conventional three-way and four-way intersections with the side-road approaches being controlled by stop signs. Pedestrian and Bicycle Facilities The developer proposes to construct an off-road trail network to connect the residential,commercial, and park areas. All urban roads would include sidewalk on both sides of the street. Bike lanes would be included on all road corridors except local residential streets. 8 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman,Montana October, 2001 Development Timeframe Construction on the property would begin as soon as the developer receives approval from the City of Bozeman, Gallatin County, and all permitting agencies. After construction begins, it is planned that the construction would take eight years to complete. It is likely that the development would reach full build-out by the year 2010. IV. TRIP GENERATION AND ASSIGNMENT In order to determine traffic volumes that would be produced by the proposed development, it was necessary to perform a trip generation analysis. RPA used the nationally accepted trip generation rates contained in Trip Generation (Institute of Transportation Engineers, Sixth Edition). The analysis involves establishing the number of trips generated by the proposed development. For the purposes of this analysis, a vehicle trip is defined as any trip that either begins or ends at the development site.It was determined that the critical traffic impacts on the intersections and roadways would most likely occur during the weekday morning and evening peak hours. Currently,the development does not have precise allocations for land use in some of the commercial areas. In order to produce trip generation rates for these areas, it was assumed that the proposed commercial areas would consist of equal proportions of area for the anticipated land uses of those areas. Using these assumptions, trip generation rates for the entire development were developed. Table 2 shows the trip generation rates and totals by land use. 9 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman,Montana October, 2001 TABLE 2 - '1 Hp Generation Rates AM Peak Land Use By Hour- AM Peak PM Peak PM Peak Weekday Phase Avg. Hour-Trip Hour- Hour-Trip - Weekday (anticipated Trip Ends Avg.Trip Ends Avg.Trip Trip Ends Completion Area Ends (% Entering Ends per (%Entering Ends per (%Entering Date) Units per Unit %Exiting) Unit % Exiting) Unit % Exiting) PHASE'l(2003) Estate Homes 32 Units 0.75 23 (25%-75%) 1.01 30 (64%-36%) 9.57 306 Transitional 20 Units 0.75 15 (25%-75%) 1.01 20 (64%-36%) 9.57 19 Homes Medium Density 60 Units 0.44 26 (17%-83%) 0.54 32 (67%-33%) 5.86 352 Residential Mixed-Use High 46 Units 0.51 23 (16%-84%) 0.62 29 (67%-33%) 6.63 305 Density Bed & Breakfast 6 Units 0.56 3 (61%-39%) 0.61 4 (53%-47%) 8.23 49 Community 1 NA NA NA Center Veterinary Office 1 NA NA NA Sum 1,031 Total 1,031 PHASE II (2004) Transitional 120 Units 0.75 90 (25%-75%) 1.01 121 (64%- 9.57 1,148 Homes 1 36% Medium Density 60 Units 0.44 26 (17%-83%) 0.54 32 (67%-33%) 5.86 352 Residential Mixed-Use High 266 Units 0.51 136 (16%- 0.62 165 (67%- 6.63 1,764 Density 84%) 33% Office Park 30,000 1.74 52 (89%-11%) 1.5 45 (14%- 11.42 343 ft2 86%) Neighborhood 40,000 1.03 41 (61%-39%) 3.74 150 (48%- 42.92 1,717 Commercial ft2 52%) Restaurant 10,000 9.27 93 (52%-48%) 10.86 109 (60%- 130.34 1,303 ft2 40%) Sum 6,627 Total 7,658 PHASE III (2005) Hotel 70 Units 0.56 39 (61%-39%) 0.61 43 (53%-47%) 8.23 576 Medium Density 80 Units 0.44 35 (17%-83%) 0.54 43 (67%-33%) 5.86 469 Residential Mixed-Use High 300 Units 0.51 153 (16%- 0.62 186 (67%- 6.63 1,989 Density 84%) 33% Office Park 30,000 1.74 52 (89%-11%) 1.5 45 (14%- 11.42 343 ft2 86%) 10 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman, Montana October, 2001 Administration 50,000 0.48 24 (88%-12%) 0.46 23 (17%-83%) 3.32 166 (Office) ft2 Neighborhood 100,000 1.03 103 (61%- 3.74 374 (48%- 42.92 4,292 Commercial ft2 39%) 52%) Restaurant 15,000 9.27 139 (52%- 10.86 163 (60%- 130.34 1,955 ft2 48%) 40%) Sum 9,790 'Total 17,448 PHASE IV (2007) Estate Homes 30 Units 0.75 23 (25%-75%) 1.01 30 (64%-36%) 9.57 287 Transitional 100 Units 0.75 75 (25%-75%) 1.01 101 (64%- 9.57 957 Homes 36% Medium Density 148 Units 0.44 65 (17%-83%) 0.54 80 (67%-33%) 5.86 867 Residential Mixed-Use High 300 Units 0.51 153 (16%- 0.62 186 (67%- 6.63 1,989 Density 84%) 33% Office Park 106,000 1.74 184 (89%- 1.5 159 (14%- 11.42 1,211 jft2 11%) 86%) Light Industrial 100 0.44 44 (83%-17%) 0.42 42 (21%-79%) 3.02 302 Research & 11,800 0.44 5 (83%-17%) 0.42 5 (21%-79%) 3.02 36 Development ft2 Sum 5,649 Total 23,097 PHASE V(2008) Single Family 280 Units 0.75 210 (25%- 1.01 283 (64%- 9.57 2,680 Homes 75% 36% Transitional 156 Units 0.75 117 (25%- 1.01 158 (64%- 9.57 1,493 Homes 75%) 36% Elementary 40,000 3.36 134 (61%- 3.12 125 (26%- 12.03 481 School ft2 39%) 74%) Park 37 NA NA 1.59 59 Sum 4,713 Total 27,810 PHASE VI (2010) Estate Homes 60 Units 0.75 45 (25%-75%) 1.01 61 (64%-36%) 9.57 574 Neighborhood 18,000 1.03 19 (61%-39%) 3.74 67 (48%-52%) 42.92 773 Commercial ft2 Sum 1,347 Total Total 29,157 11 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman,Montana October, 2001 V. TRIP DISTRIBUTION The proposed development would produce a significant amount of new traffic. It is estimated that over 29,000 new trips would be produced by the development at full build-out. However, the development would include its own residential, commercial, school, and recreation areas, so some traffic would be captured within the development itself. It is estimated that 20% of the traffic produced would stay within the development. Traffic volume levels and patterns were developed for vehicles traveling within and around the proposed development. Using the land use and trip generation numbers, the general trip pattern for the development was determined. It was calculated that only 9% of the traffic from the development would go north or west. The remaining 91% of the traffic would go east or south. FIGURE 4 shows the anticipated trip distribution by direction from the site. It was estimated that the traffic that travels between the site and North 191h Avenue would be distributed between Baxter Lane and Oak Street. The presence of the roundabouts on Baxter would likely create a shift in traffic onto Baxter Parkway. This will result in a greater use of the Oak Street corridor over the Baxter route. This means that at full build-out Baxter(Davis to N. 19`h) would carry about 40% of all the development traffic and Oak Street (Davis to N. 19`h) would carry about 56% of all development-generated traffic. FIGURE 4 - Overall Trip Distribution at Full Build-out(2010) 1 9OA k 21/r 5% m C Proposed N Development p z 1% _ Baxter Lane 1% (40% of all trips) Oak Street 28% (56% of all trips) 62% 12 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman, Montana October, 2001 VI. TRAFFIC IMPACTS WITHIN THE DEVELOPMENT Using the trip generation rates for the areas within the development, projected traffic volumes for roads within the development were calculated. An analysis of the traffic volumes indicated that the development would function adequately at full build-out. All of the resulting traffic volumes on the roads within the development can be comfortably accommodated by the proposed road system. The five modern roundabouts were evaluated with respect to how the intersection would function if they were standard three-way and four-way intersections. The analysis indicated that the Baxter/ Davis intersection would have the highest traffic volumes and would require a four-way STOP control to function adequately through Phase 3. By the end of Phase 4, traffic volumes at this intersection would likely warrant the installation of a traffic signal. The Baxter/Ferguson intersection would likely require a four-way stop control by the end of Phase 4. By end of Phase 6, the intersection of Baxter Lane and Baxter Parkway would also require signalization. The other roundabout intersections would function adequately as standard three-way and four-way intersections without the need for signalization through the end of Phase 6 of the development. The use of a modern roundabout design for the Baxter/Davis and Baxter Lane/Baxter Parkway intersections would eliminate the need for future traffic signals at these intersections and be more appropriate for the character of the area. The use of the roundabout configuration at Baxter Lane/Baxter Parkway and Davis/Baxter Parkway intersection will encourage traffic to use the Baxter Parkway and result in a desirable shift in traffic away from Baxter Lane and onto the Oak Street corridor. The roundabouts will enable left-turning traffic at these intersections to proceed without incurring the substantial delay that would occur with the standard intersection design. An analysis was conducted to determine the effectiveness of the five roundabout intersections. In each case the intersection performed better as a roundabout that it would with a standard four-way or three-way intersection. The results of this analysis are presented in TABLE 3. In each case the intersection would function better with the roundabout configuration resulting in lower average vehicle delays. 13 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman,Montana October, 2001 TABLE 3—Roundabout Evaluation at Full Build-out Standard Confi uration Roundabout Confi uration Intersection Level of Service Average Vehicle Level of Service Average Vehicle Delay Delay Baxter/Davis E* 36 seconds C 19 seconds Baxter/Unnamed C 23 seconds C 16 seconds Baxter Lane/ E* 36 seconds C 17 seconds Baxter Parkway Baxter/Ferguson B 10 seconds A 7 seconds Davis/Baxter B 12 seconds A 8 seconds Parkway * Intersection would meet signal warrants and require signalization to provide adequate LOS. Traffic volumes within the development were analyzed to determine the need for additional lanes. Within the development,Baxter Lane,Ferguson Road, and part of Davis Road are proposed as three- lane facilities with a raised center median. Traffic volumes indicated that many of the minor street intersections to these roads would also require left and through/right lanes. FIGURE 5 shows the anticipated traffic volumes within the proposed development and the intersections recommended for the addition of left and through/right lanes. VII. TRAFFIC IMPACTS OUTSIDE OF THE DEVELOPMENT In order to project the impacts that the proposed development would have on the future roadway network it is necessary to determine appropriate annual growth rates for the roadways within the vicinity of the development. Using information from the 2001 Greater Bozeman Area Transportation Plan Update, likely growth rates were determined for the area. The information indicated that the North 19`h corridor would likely.have an annual growth rate of 3.5%. However, this growth rate can not be directly applied to this development analysis. The 3.5% growth rate assumes that developments such as Baxter Meadows and Harvest Creek would be constructed in this area and reflects the traffic from these developments. Therefore, the full 3.5% growth rate can not be used to accurately assess the situation without overestimating possible traffic effects once the direct traffic from these two developments are applied Conversations with the Bozeman City planning office indicated that the Baxter Meadows and Harvest Creek developments together would account for almost all of the anticipated growth within this area over the next ten years. With this in mind, the annual growth rate for background traffic in this area was lowered to 1.5% for the development timeframe. This is a conservative estimate, but is likely much more realistic given the growth patterns in the area. 14 _I Deadman'sGulch Phase IV CD 1'rdV y CD CD CO Ca CD U 7 r c 0 ,r" i; Phase 1 0 r iL t cD Phase 1 o Phas a 11 -� 1,000 1,000 600 Baxter Lane 6,000 10,000 10,000 I 100 1,000 C o 0 a o0 to m CO 0 200 CU S o ® 100 400 0 o c Proposed 100-Acre m C.4 s Regional Park Phase V 500 5,000 0 0 0 0 C 00 1,300 Oak Street 13,000 d• 200 2,000 ® R0 LIP �l�b.,,. -O Recommend Left,Through/Right Turn Lanes Figure 5 00 = PM Peak Traffic Volume 000 =ADT Volume Traffic Volume Map Full 6uildout Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman, Montana October, 2001 Using the trip generation numbers and current traffic counts in the area it was possible to determine the Level of Service (LOS) for all intersections around the development. TABLE 4 shows the current LOS at the intersections that could be affected by the proposed development under current and 2010 traffic conditions. All of these intersections are currently signalized and modifications are expected at several intersections prior to 2010. It is expected that the Durston, Main, and College intersections on North 19`h Avenue would all be modified with new signal timing, signal phasing, and additional lanes. The anticipated intersection improvements are as follows. • Oak & 19`h—Additional right-turn-only lane for northbound traffic on 19`h. • Durston & 19`h-Fully actuated traffic signal with left, through, and right lanes on Durston. • Main & 19`h- Fully actuated traffic signal with left, two through, and right lanes on all approaches. • College and 19`h-Fully actuated traffic signal with left,two through, and right lanes on 19`h and left, through, and right lanes on College. TABLE 4—Level of Service OS Summary Without Develo ment 2001 2001 2010 2010 Intersection AM Peak PM Peak AM Peak PM Peak North 19`h&Valley Center C C C C North 19`h &Baxter B B B C North 19`h & Oak B C C* C* North 7`h & Oak C C C C North 19`h &Durston C F C* D* Main & 191 F F C* D* South 19` &College E F D* D* *With anticipated intersection improvements. It is also assumed that 191h Avenue would be modified to a five-lane facility from Main to Kagy Boulevard, and from Baxter Lane to Interstate-90. For the purpose of this analysis it was assumed that these improvements would occur before the year 2010. Without these improvements these intersections will fail even without the proposed development. The table shows that most of these intersections would continue to function adequately under 2010 conditions without the proposed development. Some intersections would have a LOS of D. However, these are some of the highest volume roads in Bozeman and a LOS of D during the peak hours will be difficult to avoid. The future road configurations in the areas around the proposed development are currently unknown. At the present time,Baxter Lane is the only paved road connecting to the site. Information from the 16 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman, Montana October, 2001 City of Bozeman Planning Office indicated that by the year 2010 it is likely that only one additional road(Oak Street)would connect to the site. It was assumed that the traffic generated by the first two phases of construction could be adequately handled with only the Baxter Lane connection. This was confirmed by performing a LOS analysis of the Baxter Lane/ 19`h Avenue intersection. The traffic volumes at the completion of phase three were then calculated to determine if any additional roads would be needed to handle the anticipated traffic volumes. This analysis indicated that by the end of phase three, an additional road would need to be connected to the development to prevent the traffic from overtaxing the Baxter/191h intersection. The additional road connection would likely be Oak Street. It was assumed that the Oak Street connection would be the only other road available through the end of phase six. This means that at full build-out, almost all of the traffic generated by the development would be funneled onto 19`h Avenue via Baxter Lane and Oak Street. Four phases of the six-phase development were analyzed to determine the impacts that the development would have on surrounding roadways. Phase 1 was not analyzed due to it's small size and short time period. Phases five and six were analyzed together due to the relatively small size of phase six. Traffic Impacts From Phases One and Two Phase one and two of this project are scheduled to be completed by 2003. By the end of phase two, the only road anticipated to be connected to the development is Baxter Drive. For this scenario, it was calculated that 98% of the trips produced by the development would use Baxter Lane for entering and exiting the site. This condition produced an ADT volume of almost 6,600 VPD on Baxter(assuming a 10% internal capture rate). Table 5 shows the level of service at intersections that may be effected by the development with and without the proposed development at the completing of phase two. The analysis shows that the only notable impact at the completion of phase two of the development would be that the intersection of North 19`h and Baxter Lane would lower from LOS B to LOS C for both A.M. and P.M. traffic conditions. No other significant impacts were identified. 17 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman,Montana October. 2001 TABLE 5—Phase Two Level of Service (LOS Summary 2003 Without Development With Develo ment Intersection AM Peak PM Peak AM Peak PM Peak North 191h &Valley Center C C C C North 19` &Baxter B B C C North 191h & Oak B* C* B* C* North 19th &Durston B* C* B* C** Oak &North 71 C* C* C* C* Main & 19`h C* D* C* D* South 19`h & College D* D* D* D* *With anticipated roadway and intersection improvements. **With additional intersection improvements. Traffic Impacts From Phase Three Phase three of the project is scheduled to be completed by 2005. By the completion of this phase it is estimated that the development would produce over 14,000 trips each day. Baxter Lane alone would not be sufficient to meet this traffic demand. However, it is likely that Oak Street would be connected to the development at part of this phase of the project. The LOS analysis for phase three is shown in TABLE 6. TABLE 6—Phase Three Level of Service (LOS) Summary 2005) Without Development With Develo ment Intersection AM Peak PM Peak AM Peak PM Peak North 191h &Valley Center C C C C North 191h &Baxter C C C C** North 19` & Oak B* C* C** C** North 19` &Durston C* C* C* C** Oak&North 7`h C* C* C* C* Main & 19`h C* D* C* D* South 19`h &College D* D* D* D* *With anticipated roadway and intersection improvements. **With additional intersection improvements. TABLE 6 shows that it would be possible for the development to produce minimal impacts at area intersections. The North 191h intersections of Baxter, Oak, and Durston would experience a small reduction in LOS. Some intersection improvements would be required to prevent this LOS degradation. These improvements are as follows: 18 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman, Montana October, 2001 • North 19`h Avenue &Baxter Lane-Install a designated right-turn lane for eastbound traffic and modify signal timing. • North 19`h Avenue & Oak Street- Install designated right-turn lane for eastbound and modify signal timing. • North 19`h Avenue &Durston Road-Modify signal timing. Traffic Impacts From Phase Four Phase four is scheduled for completion by 2008. This phase of the development would increase traffic volumes at all area intersections. TABLE 7 shows the LOS summary for phase four. TABLE 7—Phase Four Level of Service LDS Summary (2008) Without Development With Develo ment Intersection AM Peak PM Peak AM Peak PM Peak North 19'h & Valley Center C C C C North 191h &Baxter C C C** C** North 19`h & Oak C* C* C** C** North 19`h &Durston C* C* C** C** Oak &North 7` C* C* C* C* Main & 191h C* D* C* D* South 19` & College D* D* D* D* *With anticipated roadway and intersection improvements. "With additional intersection improvements. The table shows that the LOS at all intersections would remain at the same LOS under these conditions, assuming that the modifications recommended for phase three had been completed along with some additional signal timing changes. Traffic Impacts From Phases Five and Six At the completion of the sixth and final phase of the project, the proposed development would produce over 29,000 trips per day, 23,000 of which would likely make it to the surrounding road network. At this phase, some impacts would be felt along the North 19`h corridor. The LOS summary is shown in TABLE 8. 19 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman, Montana October, 2001 TABLE 8—Phase Six Level of Service (LOS) Summary (2010 Without Development With Develo ment Intersection AM Peak PM Peak AM Peak PM Peak North 191h &Valley Center C C C C North 19` &Baxter C C C** C** North 191h & Oak C C D** D** North 19` &Durston C* D* C** D** Oak &North 71h C* C* C* C* Main & 191 C* D* C* D* South 19'h & College D* D* D* D* "With anticipated roadway and intersection improvements. "*With additional intersection improvements. The table shows that most of the intersections would remain at the same LOS. However, the intersection of North 191h Avenue and Oak Street would fall to LOS D under these conditions even if lane and signal timing modifications were completed. The LOS at the other intersections would remain unchanged with some signal timing modifications. In order to determine the overall impacts of the proposed development on the entire 19`h Avenue corridor,each intersection was analyzed to determine what percentage of the total intersection traffic was generated by the proposed development. The analysis assumed that both Baxter Lane and Oak Street would connect to the site. TABLE 9 shows the results of the analysis at full build-out with year 2010 traffic volumes. TABLE 9—Percent Traffic Volumes From the Proposed Develo ment Intersection Full Build-out(2010) North 19`h & Valley Center 5% North 191h &Baxter 37% North 19t' & Oak 43% North 7` & Oak 16% 191h &Durston 35% 19`h &Main 26% South 19"' & College 15% The calculations showed that the development would account for 37% of the traffic at the Baxter/ North 19`h intersection by 2010. The Oak/North 19`h intersection would accommodate the bulk of the trips from the development. A total of 43% the traffic at this intersection would come from the Baxter Meadows development. At the Durston/North 19`h intersection 35% of the traffic at likely be from the development. South of Durston Road the percentage drops as the distance increases. 20 Traffic Impact Analysis Baxter Meadows Development Robert Peccia &Associates Bozeman, Montana October, 2001 VIII. IMPACT SUMMARY The proposed development would have a significant impact on the traffic conditions within the surrounding areas. The traffic study showed that the development would impact numerous intersections along the North 19`n Avenue corridor. The following impacts were identified. • Baxter Lane would be insufficient to meet the needs of the development under full build- out, but would function adequately through Phase two of the development. • A large proportion of the traffic would be funneled through the North 19`n/Oak intersection. With Oak Street connected to the new development, the LOS at this intersection would fall to D even with lane and signal timing improvements. With Oak Street connected to the development the LOS on Baxter Lane would remain at LOS C or better. • The North 19`n/Durston intersection would need to be reconstructed in order to meet the demands of growth within the area, despite the proposed development. The operation of this intersection would be impacted by the proposed development as well as other developments within the area. • All roads south of Durston Road on 19`n Avenue and on Huffine Lane would have minimal impacts from the proposed development. IX. RECOMMENDATIONS The following recommendations are provided to help ensure that the proposed development functions with minimal impacts on the road system in the area. • Traffic calming techniques proposed by the developer should be included in the street design. • Provide left-, through-, and right-turn lanes for eastbound traffic at the North 19`n Avenue/Oak Street intersection and North 19`n Avenue/Baxter Lane intersection. • All intersections within the development should be controlled by STOP signs on the minor street approaches. • Dedicated left-turn lanes should be provided within the development at all locations shown in FIGURE 5 of this report. • Baxter Lane between N. 19tn and Davis would probably be damaged be the construction process. The developer should correct any damage to Baxter Lane caused during the construction. • The amount of development generated traffic that will use Baxter Lane between North 19`n and Davis Road warrants that this portion of Baxter be widened to include five-foot-wide paved shoulders on both sides of the road. • Davis Street from Baxter Lane to Oak Street and Oak Street from North 19`n to Davis must 21 Traffic Impact Analysis Baxter Meadows Development Robert Peccia&Associates Bozeman, Montana October, 2001 be completed as part of the initial work in Phase three of the project. • Provide marked pedestrian crossing at all major intersections. • All of the street cross-sections shown in Exhibit "C" should be implemented. • The proposed roundabouts should be designed with a minimum inscribed circle of 110 feet with and outside diameter(at the property line) of at least 142 feet. This size roundabout will provide adequate an adequate turning radius for large trucks(WB-50)and buses.,The roundabouts should be designed according to the FHWA design guidelines for modern roundabouts and include all of the appropriate pedestrian and bicycle facilities. • The Baxter Parkway should be designed to minimize traffic conflicts.The number of side road intersections should be minimized and no direct driveway access should be allowed. On-street parking should be kept to a minimum or not allowed.All of these measures will promote the free flow of traffic and encourage the routing of traffic from the development to the Oak Street corridor. • Davis Street between Baxter Lane and Oak Street should be designed to minimize the number of side road intersections in an effort to encourage the free flow of traffic along this corridor. Direct driveway access onto this section of Davis should no be allowed. • The proposed grade separated pedestrian/bicycle crossing under Baxter Lane near the Baxter Parkway should be included as part of the development plan. This will provide an easy and safe route between the residential neighborhood to the north and the parklands to the south of Baxter. 22