Speed Limit Study: Traffic Engineering Report

Transcription

1 Speed Limit Study: Traffic Engineering Report This report documents the engineering and traffic investigation required by Vermont Statutes Annotated Title 23, Chapter for a municipal legislative body to establish a safe and reasonable speed limit for their local traffic ordinance. Municipality: Town of Ferrisburgh, Addison County, Vermont Road Name (Town Highway ): Old Hollow Rd. (TH 1 / FAS 0198) Study Location Description/ Length: From Mt. Philo Rd. to 400 East of Four Winds Rd. / About 0.6 Miles Long ATR Set up Location: Old Hollow Rd. 0.2 Mile West of Four Winds Rd. (GMPC Pole # 81) Recommended Speed Limit: Present Posted Speed Limit: 30 mph 35 mph Evaluation By: Daryl Benoit, Transportation Planner Final Report Document Date: 25 Oct 2013 (Updated 14 May 2014) 1. 85th Percentile Speed (mph): 41 mph : Eastbound / 41 mph : Westbound mph Pace Speed (mph): mph : Eastbound / 62.7% in Pace : mph : Westbound / 60.3% in Pace : 3. Average (Mean) Speed (mph): 35 mph : Eastbound / 35 mph : Westbound 4. Speed Limit Range: mph 5. Test Car speed (mph): 30 mph 6. Safe speed at curves and intersections: N/A 7. Safety problem related to speed: VTrans Crash Listings document 3 crashes with 2 injuries from on FAS 0198 between Milemarkers 0.31 & 0.89 (see attached report). 8. Average Annual Daily Traffic (vehicles per day): 1400 AADT / 90 Truck AADT (Sep 2013 count) 9. Class of Roadway: State Class III Town Highway Functional Class (07) Rural Major Collector 10. (a) Road Surface: Asphalt (b) Road Width: 22 0 (11 0 lanes) 11. (b) Shoulder Surface: Grass (b) Shoulder Width: 3 0 Eastbound lane / 3 0 Westbound lane 12. Parking: None 13. Pedestrians/Bicycles: Formal Bicycle Route 14. Adjacent Land Use: Residential, Commercial Investigation Summary: The recommended maximum speed limit of 30 mph is safe and reasonable for both directions due to the roadway geometrics and the residential nature of abutting land use. The 30 mph recommendation is lower than the 85th percentile speed, which is generally preferred in setting speed limits. However, taking into consideration other factors, such as; driveway access density, narrow setbacks of abutting roadside development (see Figure 2), shared pedestrian & vehicle use of the roadway, and crash history, the establishment of a 30 mph speed limit is reasonable. 1 Addison County Regional Planning Commission Seminary Street Middlbury, Vermont

2 Figures 1 & 2 below are views of the Automatic Traffic Recorder (ATR) set up during Sep Speed Limit Study: Traffic Engineering Report

3 Figure 3 indicates the location of ATR set up as well as the approximate milemarker positions within the study area delineating the locations of the crashes listed at the beginning of this report, and on the VTrans crash summary report (see attached). It should be noted that a traffic calming study of the Old Hollow neighborhood was initiated in 2013 to recommend strategies to lower the traffic speed on Old Hollow Rd. A copy of the report may be viewed at the following link: 3 Speed Limit Study: Traffic Engineering Report

4 Glossary: 10 mph Pace Speed (or "Pace Speed"): The 10 mph range in which the highest percentage of vehicles are traveling, 85th Percentile Speed: The maximum speed at which 85% of all vehicles are travelling. Annual Average Daily Traffic: A statistical indicator for roadway counts (i.e. traffic volume), known as the 'Annual Average Daily Traffic', or AADT, has been developed to represent the average amount of vehicular traffic in both directions of travel, passing on a given point of road, over a 24 hour period, on a typical day (i.e. seasonally adjusted) of a specified year. ATR (Automatic Traffic Recorder): A pneumatic triggered device utilizing rubber tubes installed upon a roadway to record vehicle counts, classifications, and speed data. ATRs are the tool used to capture Total Vehicle volume (used to calculate AADT), truck & bus data, 85th percentile speed, 10 MPH pace speed, Average speed data, et al. Average Speed: The statistic used to describe the typical (average or mean) value for a group of values that is calculated by dividing the sum of the observed values by the number of observed values. Class of Roadway: State and Federal classification of roadways used to identify the functional purpose and funding levels. More detailed information is available at: class/ FAS (Federal Aid System): identifying number for roads designated upon the Federal Aid System. Line of Sight (i.e. Sight Distance, Sight Line): The length of unobstructed visibility upon a roadway. Sufficient line of sight allows for enough driver reaction time and vehicle movement to avoid potential collisions. Milemarker (MM): A milemarker (i.e. milepost) is a reflective green paddle sign placed alongside highways indicating total mileage from an original control point. For Interstates, the zero milemarker originates at the southernmost, or the westernmost end of the route. However, for other types of routes, the location of the zero milemarker is placed at each municipal boundary. The Vermont Agency of Transportation (VTrans) manages their milemarkers from South to North, or West to East, depending on the direction of travel of a particular route. Speed Limit Range: The lowest number of 10 mph Pace Speed divided by a higher number. This higher number is the lower value of either; A. The 85 th percentile speed, or B. The highest value of the 10 mph Pace Speed. This higher number is then subtracted from 3. Stopping Sight Distance (SSD): The minimum distance a driver can see ahead in tandem with how long it takes for her/him to stop the vehicle. According to the AASHTO Green Book, this distance is comprised of two components; 1. Perception Reaction Time, which covers the distance a vehicle travels from the moment the driver sees an object necessitating a stop, to the instant the brakes are applied, and 2. Braking Distance, which is the distance a vehicle travels during the braking maneuver. Test Car Speed: A qualitative measure determined by the person conducting the speed limit engineering study by driving the road for a few passes and using their "gut" to determine what "feels" to be a reasonable speed. Traffic Calming: The use of educational programs, enforcement, and engineering to change the behavior of drivers, reduce crash/injury rates, and increase safety. Vermont State Standards (VSS): Formally known as the Vermont State Standard for the Design of Transportation Construction, Reconstruction and Rehabilitation on Freeways, Roads and Streets, VSS were developed during the mid 1990 s to standardize the physical design parameters and guidelines of Vermont bridges and roadways. VSS was initially created for two purposes: 1. To provide clear technical direction to the designers of transportation projects in Vermont, and; 2. To achieve roadway and bridge designs which provide access, mobility and safety for users, and which are also sensitive to the social and environmental context of Vermont. These standards are purportedly under review to be updated in Speed Limit Study: Traffic Engineering Report

5 Appendices: 1. Crash Report Summary: Automatic Traffic Recorder (ATR) reports and data may be downloaded from: 5 Speed Limit Study: Traffic Engineering Report

6 Page: 1181 Vermont Agency of Transportation Date: 08/07/2013 General Yearly Summaries - Crash Listing: State Highways and All Federal Aid Highway Systems From 01/01/08 To 12/31/12 General Yearly Summaries Information * Reporting Agency/ Town Mile Marker Date MM/DD/YY Time Weather Contributing Circumstances Direction Of Collision Of Injuries Of Fatalities Of Untimely Deaths Direction Road Group Route: FAS 0197 Continued... Monkton /16/ :30 Clear No improper driving Single Vehicle Crash MC (FAS) 1159 VT / Monkton UNK 01/18/ :16 Snow No improper driving Other - Explain in Narrative N MC (FAS) Route: FAS VTVSP0600/12C VTVSP0600/12C Route: FAS 0199 VT /08BR VT /12BR VT /09BR VT /11BR VTVSP0600/10C VTVSP0600/10C Ferrisburgh /26/ :18 Clear Failure to keep in proper lane Single Vehicle Crash E MC (FAS) Ferrisburgh /02/ :15 Snow No improper driving, Failed to yield right of way, Driving too fast for conditions No Turns, Thru moves only, Broadside ^< E MC (FAS) Ferrisburgh /03/ :59 Rain Driving too fast for conditions, Disregarded Single Vehicle Crash S MC (FAS) traffic signs, signals, road markings Ferrisburgh /12/ :37 Snow Driving too fast for conditions, Disregarded Right Turn and Thru, Same Direction S MC (FAS) traffic signs, signals, road markings, No Sideswipe/Angle Crash ^^-- improper driving Ferrisburgh /29/ :50 Rain Driving too fast for conditions, Failure to Single Vehicle Crash E MC (FAS) keep in proper lane Ferrisburgh /28/ :56 Snow Driving too fast for conditions Single Vehicle Crash W MC (FAS) Monkton /25/ :20 Clear Made an improper turn, No improper driving Left Turn and Thru, Broadside v< MC (FAS) Monkton /31/ :34 Snow No improper driving, Driving too fast for Opp Direction Sideswipe N MC (FAS) conditions Monkton /01/ :26 Clear Failure to keep in proper lane Single Vehicle Crash MC (FAS) Monkton /29/ :22 Sleet, Hail (Freezing Failure to keep in proper lane Single Vehicle Crash MC (FAS) Rain or Drizzle) Monkton /10/ :13 Cloudy Failure to keep in proper lane, Distracted Single Vehicle Crash N MC (FAS) Monkton /26/ :02 Clear Failure to keep in proper lane, No improper Opp Direction Sideswipe N MC (FAS) driving Monkton /19/ :50 Cloudy Failure to keep in proper lane Single Vehicle Crash W MC (FAS) Bristol /08/ :20 Rain Driving too fast for conditions, Operating defective equipment, No improper driving Rear End N MC (FAS) Bristol /24/ :51 Clear Exceeded authorized speed limit, Single Vehicle Crash MC (FAS) Inattention Bristol /14/ :24 Clear Distracted, No improper driving Rear End N MC (FAS) Bristol /09/ :56 Cloudy No improper driving, Failed to yield right of way No Turns, Thru moves only, Broadside ^< MC (FAS) Bristol /27/ :39 Cloudy Technology Related Distraction, Single Vehicle Crash E MC (FAS) Disregarded traffic signs, signals, road markings Bristol /22/ :32 Cloudy Failure to keep in proper lane, Fatigued, Single Vehicle Crash N MC (FAS) asleep Bristol /23/ :37 Cloudy Failed to yield right of way, Followed too Rear End N MC (FAS) closely Bristol /15/ :50 Cloudy Failure to keep in proper lane, Fatigued, Single Vehicle Crash MC (FAS) asleep Bristol /17/ :30 Clear Failure to keep in proper lane, Driving too Single Vehicle Crash S MC (FAS) fast for conditions Bristol /21/ :41 Cloudy Driving too fast for conditions Single Vehicle Crash N MC (FAS) Bristol /08/ :33 Cloudy Failure to keep in proper lane Single Vehicle Crash MC (FAS) *Crash occurred prior to the last Highway Improvement Project. This data should not be used in a crash analysis. UNK indicates the Mile Marker is Unknown.