Transit / Traffic EngineeringOperational Impacts & Safety Improvements

(Mark Ingram, PE, PTOE) – Alliance Transportation Group

Traffic Engineering

Safety

What can be done to reduce crashes?

Safety

MobilityReliability

Mobility

Are the operations managed

efficiently?

How long before operations fail?

Reliability

Is the system going to be dependable?

Traffic Engineering (Modes of Travel)

• Cars

• Trucks

• Pedestrians

• Bicycle

• Transit

Standards / Guidance / Local Practices

Manual on Uniform Traffic Control Devices

AASHTO - A Policy on Geometric Design of Highway and Streets

AASHTO - Highway Safety Manual

AASHTO - Pedestrian Facilities Manual

• Pedestrian access is essential• Sidewalk placement and width

• Pedestrian Buffers (landscaping)

• Crossing measures

• ADA Compliance

• Maintain Visual Quality• Lighting

• Landscaping

• Safe environment

Pedestrian Safety in Transit Design

• Pedestrian Safety Guide for Transit Agencies• FHWA

• Perform a transit stop audit• Difficult roadway crossings

• Incomplete sidewalks (connectivity)

• Inadequate sidewalk width

• Marked crosswalks

• HAWK Signalization• High-Intensity Activated crossWalK beacon

Multimodal Considerations

Multimodal Considerations

• Service Measures• Service frequency

• Speed

• Pedestrian Level of Service (LOS)

• As a system• Weighted average of LOS scores.

• Complete Streets transitions to Complete Networks

Transportation Focus (The User)

• Varying points of view (Transit Agency, City, Parish/County, State)• Sometimes it can become competitive between the agencies.

• Step back and focus on the user.

• User wants convenience, efficient travel, and safety.

• Work together to find solutions that meet the user goals.

Traffic Engineering Analysis-Tools of the Trade

• Regional Transportation Planning Models

• Highway Capacity Manual (operational analysis)

• Transit Capacity and Quality of Service Manual

• Microsimulation

Traffic Engineering Options for Transit Operations• Turning Restrictions / Allowances

• Traffic Signal Shadowing

• Transit Signal Priority

• Queue Jumps

• Bus Only Phases

Traffic Signal Shadowing

• Used when signal is not

warranted

• Creates gaps in flow

• Improves safety

• Improves reliability

Transit Signal Priority

• Applied at locations

with heavy delay

• Consistent with

regional mobility goals

• Improved reliability

• Results in improved

person throughput

Queue Jumping

• Applied at congested

intersections

• Improved reliability

Bus Only Phases

• Similar to queue

jump

• Improves reliability

Conclusion

• Goals are to improve safety and mobility for the public

• Implement strategies to improve transit reliability with regional mobility of all modes of traffic in mind