Presentation on theme: "Carter Danne, PE, PTOE Parametrix, Inc. Assessment of Point Defiance Bypass for High-Speed Intercity Passenger Rail."— Presentation transcript:
Carter Danne, PE, PTOE Parametrix, Inc. Assessment of Point Defiance Bypass for High-Speed Intercity Passenger Rail
Project Definition & Orientation Effects on Roadways Presentation Outline Intent: Educate on lessons learned and leave you with a basic understanding of the project.
Washington State Department of Transportation (WSDOT) Federal Railroad Administration (FRA) Who are the project leads?
Cities of DuPont, Lakewood, and Tacoma Pierce County Sound Transit Clover Park School District Joint Base Lewis McChord (JBLM) Camp Murray Federal Highway Administration (FHWA) Who are the project partners?
Prepare a Transportation Discipline Report (TDR) Synthesize LOS, Delay, and Queuing information prepared by HDR Complete a safety analysis What was our role?
Where is Point Defiance? Why bypass it?
What about station improvements?
Better service for Amtrak Cascades and Coast Starlight routes (14 more daily train trips) Better multimodal connections with commuter rail and light rail Fewer conflicts for freight rail on existing alignment What does it mean for rail operations?
21 at-grade crossings 47 study intersections Level of service (LOS) and intersection delay Maximum queues Safety How does the Project affect roadways?
Quantity of Intersections Intersection EffectAM Peak HourPM Peak Hour Slight to No Noticeable Effect (Delay change of 5 seconds or less per vehicle) 4341 Improved Functioning (Delay improvements of more than 5 seconds per vehicle) 33 Adversely Affected (Delay increases greater than 5 seconds per vehicle) 13 Roadway volumes similar between alternatives One additional train per peak hour Project has some improvements built into it LOS and Intersection Delay LOS was of limited use as measures of effectiveness (MOE) because the project train trips were infrequent.
Effect on Maximum Queue Lengths Overall 2-4 vehicles longer with proposed Project Additional Intersections Blocked by Maximum Queues S. Washington Street & S. 51 st Street (PM Peak Hour Only) Roadway blockage duration approximately one minute or less when not near a station Similar blockage time to commuter rail in corridor Signal improvements built into the project would help Maximum Queues Use graphics to supplement queue tables. Record maximum queues following the train crossing event until the system returns to normal.
StreetMovementStorage (feet) Peak Hour Maximum Queues (feet) No Action Build S. 56 th Street EB Left50AM PM EB Through 125 RRAM224 B225 B PM237 B238 B EB RightSharedAM224 B225 B PM237 B238 B S. 56 th Street WB LeftSharedAM PM WB Through 225 I/SAM PM391 WB RightSharedAM PM391 S. Washington Street NB Left75AM42 PM4850 NB Through 600 I/SAM58 PM64 NB RightSharedAM60 PM66 S. Washington Street SB Left100AM6769 PM SB Through 600 I/SAM50 PM800 B1219 B SB RightSharedAM9195 PM Maximum Queues – Example Storage distances estimated to the nearest 25 feet. IS Distance to next upstream roadway. RR Distance reported to upstream railroad crossing. _ Queue extends beyond lane storage. B Blocks access to turn pocket or channelized right-turn.
Safety - Crossing Area Improvements Do Not Stop On Tracks signs Wayside horns Median barriers Sidewalks Pre-signals More advanced signal controllers
Predicted Accident Experience Methodology Railroad-Highway Grade Crossing Handbook – Revised Second Edition 2007 US DOT accident prediction model for railroad- highway grade crossings Five years of most recently available accident data Input crossing characteristics Year 2030 conditions
Units of Accident Experience PerspectiveUnits US DOT Accident Prediction Formula Accidents per year (annual frequency) PublicYears between accidents (recurrence interval), e.g., 1 accident in 18 years. Exposure-basedAccidents per one million train crossings Remember, document units in meaningful terms to your audience.
Expected Accident Experience – Accidents per Million Train Crossings Route No Action Alternative Build Alternative Bypass Route Bypass Route and Point Defiance Route Combined
Expected Accident Experience – Years between Accidents Corridor Summary Years between Accidents Change Build vs. No Action Route No Action Alternative Prediction Build Alternative Prediction Time between Accidents Point Defiance Route years longer Bypass Route years shorter Both Routes Combined years shorter
Accident Experience Thresholds Active Devices without GatesActive Devices with Gates When the expected accident frequency* exceeds 0.1 accidents per year (1 accident every 10 years), consider active devices with gates. When the expected accident frequency* exceeds 0.5 accidents per year (1 accident every 2 years), consider grade separation. * As predicted by the US DOT Accident Prediction Formula. Note: These apply regardless of whether or not the improvements are economically justifiable.
Expected Accident Experience – Greatest Effects on Individual Crossings Individual Crossings Years between Accidents Change Build vs. No Action Crossing Crossing ID No Action Alternative Prediction Build Alternative Prediction In Years In Train Volume Bridgeport Way SW085821P % Barksdale Ave085836E %
Basic understanding of the Project Effects on roadways Lessons learned More information: Carter Danne, PE, PTOE Parametrix, Inc. office cell Thank You!