MUTCD: Comments due May 14, 2021
The volume of transit vehicles and passengers moving through and stopping on a street are key factors in both the selection of street elements and their detailed design. Street design has an interactive effect on transit frequency, both supporting transit at different volumes, and attracting passengers to different degrees. For decisions about street space and time allocation, the combined frequency of all routes is more significant than the frequency of any given route.
Frequency is discussed here in the context of standard buses during peak periods. For larger vehicles, consider both ridership and vehicle frequency in determining spatial needs.
Street design must accommodate transit vehicle geometry, but passenger and pedestrian safety and access are often larger issues on lower-use routes. Many express and coverage routes have low frequencies, with schedule adherence and general reliability the primary concern for passengers and operators alike.
Active transit signal priority (TSP) has relatively strong benefits for transit and minimal impacts on other modes.
Enhancing stops improves comfort and customer confidence.
Passenger information both at stops and online is critical to basic usability of the service.
Providing a qualitatively different service than low frequency routes, transit lines that are part of a frequent network should be kept prompt and reliable for easy transfers, overall usability, and a good passenger experience. These transit streets have room for growth, and services must be as competitive as possible.
Traffic delay, rather than dwell time, is usually the main source of delay. Intersection priority focused on reliability, and dedicated lanes at slow points, can put these services on the path to growing ridership.
Street design should prioritize transit stop convenience and provide transit vehicles with a preferred position in traffic, including in-lane stops and other priority treatments.
Moderately frequent service can be integrated into spaces shared with active modes, including shared streets.
With transit arriving every few minutes, schedule adherence is less important to passengers than wait time, and maintaining headways matters for reliability as well as speed.
At these high service frequencies, buses and rail vehicles have a major influence on general traffic operations, and might account for a majority of travel on the street. Providing dedicated lanes or improving existing dedicated lanes can expand total street capacity, attracting more passengers. Transit can easily become the fastest mode on a street if given space.
If multiple routes operate or long dwell times occur, refer to very high volume guidance.
The performance of transit on streets where multiple routes converge at key points in the network often determines the fate of the entire transit network. On these highly productive transit streets, transit will dominate the streetscape whether or not the design prioritizes it effectively. Exclusive transit lanes are crucial for maintaining speed and reliability.
At headways of 3 minutes and shorter, buses and rail vehicles carry thousands of passengers per hour, and must be insulated from general traffic delay. Dedicated lanes or transitways are indispensable for the efficient movement of people. Stop capacity is a critical operational factor.
Signal and intersection operations should favor transit, with transit-friendly signal progressions or dedicated transit phases providing stronger benefits than active transit signal priority.