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HomeMy WebLinkAboutApp. F. - Traffic Impact Study Supplement #3 9-10-2020 130 South Howie Street Helena, Montana 59601 406-459-1443 September 3, 2020 Taylor Lonsdale, PE City of Bozeman 20 E. Olive St. Bozeman, MT 59715 RE: Norton East Ranch Phase 5 TIS Supplement #3 Dear Taylor, Abelin Traffic Services has developed supplemental information for the April 2020 Norton East Ranch Phase 5 Subdivision TIS. This additional information is in response to email comments and questions received from the City of Bozeman on 8- 26-2020. The detailed responses to the comments and questions are as follow: Fallon Street Level of Service Regarding the projected poor LOS operations at the intersection of Fallon Street and Cottonwood Road identified in the report, the April 2020 TIS indicated that the new traffic signal at Babcock Street and Cottonwood Road would largely correct the traffic impacts at Fallon Street for the near future. This conclusion was based on the fact the LOS issues at the Fallon Street intersection are largely caused by traffic attempting to turn left from Fallon Street onto Cottonwood Road or traffic attempting to cross Cottonwood Road. Commuter traffic attempting to use Cottonwood Road from any location within the Norton developments or the other nearby developments this area can now easily redirect to the traffic signal at Babcock Street using water Lilly Driven or Automotive Drive, which largely eliminates the need for a traffic signal at Fallon Street at this time. As commercial development increases along Fallon Street with the later phases of Norton development or major commercial developments occur along Fallon Street east of Cottonwood Road, a traffic signal at this location will likely become warranted. However, Phases 1-6 of the Norton development will not significantly contribute to the need for a traffic signal at Fallon Street and would not benefit from the installation of the traffic signal at that location in light of the recently completed traffic signal at Babcock Street. Laurel Parkway North Connection An analysis was performed for the project assuming Laurel Parkway is not fully connected north to Durston Road with the initial phases of the project. Under this scenario, Phases 5A and 5C would be developed to include 78 residential units from Boomtown Road south to Babcock Street. This analysis assumed that all other previous phases of the Norton East Ranch Development and the additional projects in this area are constructed. Based on the number of proposed units in Phases 5A & 5C this initial phase 2 of the project would produce 736 daily vehicle trips compared to 1,303 at full buildout of Phase 5. Phase 5A & 5C Trip Generation Rates Land Use Units AM Peak Hour Trip Ends per Unit Total AM Peak Hour Trip Ends PM Peak Hour Trip Ends per Unit Total PM Peak Hour Trip Ends Weekday Trip Ends per Unit Total Weekday Trip Ends Phase 5A & 5C ITE #210 78 Units 0.74 58 (14 in/44 out) 0.99 77 (49 in/28 out) 9.44 736 Without the Laurel Parkway connection to Durston Road from the Norton East Ranch Development, all traffic that was originally predicted to go north to Durston Road would be redirected east to Cottonwood Road via Babcock Street. The original operational analysis of this configuration suggested that the intersection at Babcock Street and Cottonwood Road would be nearing capacity with the previous STOP control configuration. However, the traffic signal and lane improvements constructed at this location in the summer of 2020 added considerable capacity to this intersection. This new traffic signal has the capacity to function at LOS C with more than twice the currently predicted traffic with Norton East Ranch Phase 5 and the other planned developments in this area (see attached LOS worksheets). Future Level of Service Summary Phase 5A & P5C AM Peak Hour PM Peak Hour Intersection Delay (Sec.) LOS Delay (Sec.) LOS Cottonwood Road & Durston Road Traffic Signal Existing Traffic 12.3 B 13.1 B Cottonwood Road & Durston Road Traffic Signal with 2X Projected Traffic From Norton East Ranch Phase 5A & 5C 20.1 C 18.3 B While the connection of Laurel Parkway to the north will eventually become an important part of the overall street network though this portion of Bozeman, there is no specific need to include the connection with the initial development of Phase 5 of this project from an operational perspective. The new signal at Babcock and Cottonwood will provide sufficient capacity to serve the initial phases of the Norton East Ranch Phase 5 project with minimal delay. The developers should provide the connection north to Durston Road with later phases of the Norton East Ranch Phase 5 project as planned. 3 Laurel Parkway Traffic Control Improvements It is likely that the intersection of Durston Road and Laurel Parkway will eventually require a higher form of traffic control (traffic signal or roundabout). The April 2020 TIS projected that the intersection will likely function at LOS F by 2035 as a four-way STOP with the projected traffic growth in this area. This issue was also identified in the 2017 Bozeman Transportation Plan. The April 2020 TIS did not recommend improvements to this intersection with the Norton East Ranch Phase 5 as no improvement warrants will be met until the existing 4-way STOP traffic controls begin the fail. The City of Bozeman requested additional information about when this intersection will likely begin to experience operational problems. ATS performed LOS calculations to determine how much additional traffic would be required at the intersection before LOS problems occur. This analysis suggests that the exiting four-way STOP will function at LOS C or better through construction of Phase 5 AND Phase 6 of the Norton developments PLUS an additional 20-30% traffic volume growth on Durston Road (see attached LOS worksheets). The future 2035 traffic volume projections for this intersection included in the April 2020 TIS anticipated a 60% traffic volume increase on Durston Road by 2035. Therefore, it can be safely assumed that a higher form of traffic control will not be warranted at this location until approximately 2027, even with full development of Norton Phases 5 & 6. It would be desirable to study this intersection again in detail between Phase 5 and Phase 6 of the development to more accurately identify when intersection improvements will be warranted. If you have any additional questions regarding the traffic impacts from this project, please feel free to contact me at 459-1443. Sincerely, Bob Abelin, P.E. PTOE Abelin Traffic Services, Inc. HCS7 Signalized Intersection Results Summary General Information Intersection Information Agency ATS Duration, h 0.250 Analyst RLA Analysis Date Apr 2, 2020 Area Type Other Jurisdiction City of Bozeman Time Period AM Peak With Development PHF 1.00 Urban Street Cottonwood Road Analysis Year 2025 Analysis Period 1> 7:00 Intersection Babcock Street File Name BabcockSignalwithAMalt.xus Project Description Norton Ranch Phase 5- No LP Demand Information EB WB NB SB Approach Movement L T R L T R L T R L T R Demand ( v ), veh/h 82 41 75 72 26 18 54 436 16 30 550 89 Signal Information Green Yellow Red 3.2 1.3 60.0 13.6 0.0 0.0 4.0 0.0 4.0 4.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Cycle, s 90.0 Reference Phase 2 Offset, s 0 Reference Point End Uncoordinated No Simult. Gap E/W On Force Mode Fixed Simult. Gap N/S On Timer Results EBL EBT WBL WBT NBL NBT SBL SBT Assigned Phase 4 8 5 2 1 6 Case Number 6.0 6.0 1.1 4.0 1.1 4.0 Phase Duration, s 17.6 17.6 8.4 65.2 7.2 64.0 Change Period, ( Y+R c ), s 4.0 4.0 4.0 4.0 4.0 4.0 Max Allow Headway ( MAH ), s 3.2 3.2 3.1 0.0 3.1 0.0 Queue Clearance Time ( g s ), s 9.1 13.0 2.9 2.5 Green Extension Time ( g e ), s 0.6 0.5 0.1 0.0 0.0 0.0 Phase Call Probability 1.00 1.00 0.74 0.53 Max Out Probability 0.00 0.00 0.00 0.00 Movement Group Results EB WB NB SB Approach Movement L T R L T R L T R L T R Assigned Movement 7 4 14 3 8 18 5 2 12 1 6 16 Adjusted Flow Rate ( v ), veh/h 82 116 72 44 54 227 225 30 327 312 Adjusted Saturation Flow Rate ( s ), veh/h/ln 1362 1543 1276 1605 1641 1723 1701 1641 1723 1639 Queue Service Time ( g s ), s 5.0 6.2 4.9 2.2 0.9 4.4 4.4 0.5 7.0 7.1 Cycle Queue Clearance Time ( g c ), s 7.1 6.2 11.0 2.2 0.9 4.4 4.4 0.5 7.0 7.1 Green Ratio ( g/C )0.15 0.15 0.15 0.15 0.72 0.68 0.68 0.70 0.67 0.67 Capacity ( c ), veh/h 255 234 187 243 623 1172 1157 708 1147 1091 Volume-to-Capacity Ratio ( X )0.321 0.496 0.386 0.181 0.087 0.194 0.194 0.042 0.285 0.286 Back of Queue ( Q ), ft/ln ( 50 th percentile)41.9 58.6 39 21 5.7 35.4 34.6 3.4 58.7 55.6 Back of Queue ( Q ), veh/ln ( 50 th percentile)1.6 2.3 1.5 0.8 0.2 1.4 1.4 0.1 2.3 2.2 Queue Storage Ratio ( RQ ) ( 50 th percentile)0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Uniform Delay ( d 1 ), s/veh 36.4 35.0 40.1 33.3 4.1 5.3 5.3 4.3 6.2 6.2 Incremental Delay ( d 2 ), s/veh 0.3 0.6 0.5 0.1 0.0 0.4 0.4 0.0 0.6 0.7 Initial Queue Delay ( d 3 ), s/veh 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Control Delay ( d ), s/veh 36.6 35.6 40.5 33.4 4.1 5.7 5.7 4.3 6.8 6.9 Level of Service (LOS)D D D C A A A A A A Approach Delay, s/veh / LOS 36.1 D 37.8 D 5.5 A 6.7 A Intersection Delay, s/veh / LOS 12.6 B Multimodal Results EB WB NB SB Pedestrian LOS Score / LOS 2.30 B 2.30 B 1.86 B 1.86 B Bicycle LOS Score / LOS 0.81 A 0.68 A 0.91 A 1.04 A Copyright © 2020 University of Florida, All Rights Reserved. HCS™ Streets Version 7.8.5 Generated: 7/20/2020 9:55:31 AM HCS7 Signalized Intersection Results Summary General Information Intersection Information Agency ATS Duration, h 0.250 Analyst RLA Analysis Date Apr 2, 2020 Area Type Other Jurisdiction City of Bozeman Time Period PM Peak With Development PHF 1.00 Urban Street Cottonwood Road Analysis Year 2025 Analysis Period 1> 7:00 Intersection Babcock Street File Name BabcockSignalwithPMalt.xus Project Description Norton Ranch Phase 5 - No LP Demand Information EB WB NB SB Approach Movement L T R L T R L T R L T R Demand ( v ), veh/h 124 28 54 7 28 56 96 373 96 23 230 86 Signal Information Green Yellow Red 2.6 2.8 57.5 15.0 0.0 0.0 4.0 0.0 4.0 4.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Cycle, s 90.0 Reference Phase 2 Offset, s 0 Reference Point End Uncoordinated No Simult. Gap E/W On Force Mode Float Simult. Gap N/S On Timer Results EBL EBT WBL WBT NBL NBT SBL SBT Assigned Phase 4 8 5 2 1 6 Case Number 6.0 6.0 1.1 4.0 1.1 4.0 Phase Duration, s 19.0 19.0 9.5 64.4 6.6 61.5 Change Period, ( Y+R c ), s 4.0 4.0 4.0 4.0 4.0 4.0 Max Allow Headway ( MAH ), s 3.3 3.3 3.1 0.0 3.1 0.0 Queue Clearance Time ( g s ), s 14.5 6.6 3.6 2.4 Green Extension Time ( g e ), s 0.5 0.6 0.1 0.0 0.0 0.0 Phase Call Probability 1.00 1.00 0.91 0.44 Max Out Probability 0.00 0.00 0.00 0.00 Movement Group Results EB WB NB SB Approach Movement L T R L T R L T R L T R Assigned Movement 7 4 14 3 8 18 5 2 12 1 6 16 Adjusted Flow Rate ( v ), veh/h 124 82 7 84 96 241 228 23 162 154 Adjusted Saturation Flow Rate ( s ), veh/h/ln 1314 1540 1316 1538 1641 1723 1601 1641 1723 1565 Queue Service Time ( g s ), s 8.3 4.2 0.4 4.3 1.6 4.8 4.9 0.4 3.4 3.5 Cycle Queue Clearance Time ( g c ), s 12.5 4.2 4.6 4.3 1.6 4.8 4.9 0.4 3.4 3.5 Green Ratio ( g/C )0.17 0.17 0.17 0.17 0.71 0.67 0.67 0.67 0.64 0.64 Capacity ( c ), veh/h 237 257 239 257 816 1155 1074 675 1101 1000 Volume-to-Capacity Ratio ( X )0.523 0.319 0.029 0.327 0.118 0.208 0.212 0.034 0.147 0.154 Back of Queue ( Q ), ft/ln ( 50 th percentile)66.8 39.4 3.4 40.4 10.8 39.9 37.4 3.1 29.1 27.5 Back of Queue ( Q ), veh/ln ( 50 th percentile)2.6 1.6 0.1 1.6 0.4 1.6 1.5 0.1 1.1 1.1 Queue Storage Ratio ( RQ ) ( 50 th percentile)0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Uniform Delay ( d 1 ), s/veh 38.5 33.0 35.0 33.0 4.2 5.7 5.7 5.1 6.5 6.5 Incremental Delay ( d 2 ), s/veh 0.7 0.3 0.0 0.3 0.0 0.4 0.5 0.0 0.3 0.3 Initial Queue Delay ( d 3 ), s/veh 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Control Delay ( d ), s/veh 39.2 33.3 35.0 33.3 4.2 6.1 6.1 5.1 6.8 6.8 Level of Service (LOS)D C C C A A A A A A Approach Delay, s/veh / LOS 36.8 D 33.4 C 5.8 A 6.7 A Intersection Delay, s/veh / LOS 13.5 B Multimodal Results EB WB NB SB Pedestrian LOS Score / LOS 2.30 B 2.30 B 1.86 B 1.87 B Bicycle LOS Score / LOS 0.83 A 0.64 A 0.95 A 0.77 A Copyright © 2020 University of Florida, All Rights Reserved. HCS™ Streets Version 7.8.5 Generated: 7/20/2020 9:28:11 AM HCS7 All-Way Stop Control Report General Information Site Information Analyst RLA Intersection Laurel Parkway & Durston Agency/Co.ATS Jurisdiction City of Bozeman Date Performed 9/11/2019 East/West Street Durston Road Analysis Year Max North/South Street Laurel Parkway Analysis Time Period (hrs)0.25 Peak Hour Factor 1.00 Time Analyzed AM With Developments Project Description Norton Ranch Phase 5 Lanes Vehicle Volume and Adjustments Approach Eastbound Westbound Northbound Southbound Movement L T R L T R L T R L T R Volume 68 510 37 36 380 40 46 14 42 80 10 112 % Thrus in Shared Lane Lane L1 L2 L3 L1 L2 L3 L1 L2 L3 L1 L2 L3 Configuration L TR L TR L TR LT R Flow Rate, v (veh/h)68 547 36 420 46 56 90 112 Percent Heavy Vehicles 1 2 2 1 2 2 2 1 Departure Headway and Service Time Initial Departure Headway, hd (s)3.20 3.20 3.20 3.20 3.20 3.20 3.20 3.20 Initial Degree of Utilization, x 0.060 0.486 0.032 0.373 0.041 0.050 0.080 0.100 Final Departure Headway, hd (s)6.69 6.16 6.91 6.32 8.24 7.21 7.93 6.77 Final Degree of Utilization, x 0.126 0.935 0.069 0.738 0.105 0.112 0.198 0.211 Move-Up Time, m (s)2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 Service Time, ts (s)4.39 3.86 4.61 4.02 5.94 4.91 5.63 4.47 Capacity, Delay and Level of Service Flow Rate, v (veh/h)68 547 36 420 46 56 90 112 Capacity 538 585 521 569 437 499 454 532 95% Queue Length, Q₉₅ (veh)0.4 12.2 0.2 6.3 0.4 0.4 0.7 0.8 Control Delay (s/veh)10.4 47.3 10.1 24.7 11.9 10.8 12.6 11.3 Level of Service, LOS B E B C B B B B Approach Delay (s/veh)43.2 23.5 11.3 11.9 Approach LOS E C B B Intersection Delay, s/veh | LOS 29.7 D Copyright © 2020 University of Florida. All Rights Reserved. HCS™AWSC Version 7.8.5 Generated: 9/3/2020 10:40:28 AMLaurelAMwithMax.xaw HCS7 All-Way Stop Control Report General Information Site Information Analyst RLA Intersection Laurel Parkway & Durston Agency/Co.ATS Jurisdiction City of Bozeman Date Performed 9/11/2019 East/West Street Durston Road Analysis Year Max North/South Street Laurel Parkway Analysis Time Period (hrs)0.25 Peak Hour Factor 1.00 Time Analyzed PM With Developments Project Description Norton Ranch Phase 5 Lanes Vehicle Volume and Adjustments Approach Eastbound Westbound Northbound Southbound Movement L T R L T R L T R L T R Volume 68 520 47 73 250 28 38 13 75 96 31 64 % Thrus in Shared Lane Lane L1 L2 L3 L1 L2 L3 L1 L2 L3 L1 L2 L3 Configuration L TR L TR L TR LT R Flow Rate, v (veh/h)68 567 73 278 38 88 127 64 Percent Heavy Vehicles 1 2 2 1 2 2 2 1 Departure Headway and Service Time Initial Departure Headway, hd (s)3.20 3.20 3.20 3.20 3.20 3.20 3.20 3.20 Initial Degree of Utilization, x 0.060 0.504 0.065 0.247 0.034 0.078 0.113 0.057 Final Departure Headway, hd (s)6.59 6.05 6.97 6.38 8.00 6.90 7.71 6.61 Final Degree of Utilization, x 0.124 0.952 0.141 0.493 0.084 0.169 0.272 0.118 Move-Up Time, m (s)2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 Service Time, ts (s)4.29 3.75 4.67 4.08 5.70 4.60 5.41 4.31 Capacity, Delay and Level of Service Flow Rate, v (veh/h)68 567 73 278 38 88 127 64 Capacity 547 595 517 564 450 521 467 544 95% Queue Length, Q₉₅ (veh)0.4 12.9 0.5 2.7 0.3 0.6 1.1 0.4 Control Delay (s/veh)10.2 50.0 10.8 15.1 11.4 11.0 13.3 10.2 Level of Service, LOS B F B C B B B B Approach Delay (s/veh)45.8 14.2 11.1 12.2 Approach LOS E B B B Intersection Delay, s/veh | LOS 29.0 D Copyright © 2020 University of Florida. All Rights Reserved. HCS™AWSC Version 7.8.5 Generated: 9/3/2020 10:41:18 AMLaurelPMwithMax.xaw