Bus Stop Location & Roadway Design

Bus stop placement directly impacts the convenience and accessibility of the system. The final decision on bus stop locations is dependent on ease of operation, pedestrian transfer situations, space availability, and traffic operations. Pace performs on-site evaluations of proposed bus stops to analyze operating conditions and identify appropriate bus stop locations. All bus stop locations should be designed to accommodate at least one 45-foot bus, with an additional 45 feet of queuing space per vehicle when multiple transit vehicles are expected to utilize the bus stop simultaneously.

Developers and/or municipalities should consult Pace’s Transportation Engineer during their initial development planning stages to identify potential bus stop locations and to coordinate the placement of Pace signs.

Pace asks that municipalities place “No Parking” signs at bus stop locations and that local police strictly enforce parking restrictions in these zones.

Far-Side Bus Stops

Far-side bus stops are located immediately after an intersection, allowing the vehicle to pass through the intersection before stopping for passenger loading and unloading. When the bus reenters the traffic stream, the upstream signal regularly generates gaps in traffic allowing buses to reenter the traffic lane. Far-side stops require shorter deceleration distances and provide for additional right turn capacity by eliminating bus blockage within the curb lane on the approach to the intersection. Additionally, the location of the stop encourages pedestrians to cross behind the bus. For these safety and capacity benefits, far-side stops are preferred by IDOT (Bureau of Local Roads & Streets Manual, Special Design Elements, IDOT, pg. 41-4(1), 2006) and Pace if traffic signal and geometry conditions are favorable.

During peak periods, however, when bus queuing is possible, intersections may be blocked by buses waiting to access the bus stop. The act of accelerating at an intersection and then immediately decelerating at the bus stop has the potential to increase the number of rear-end collisions. Additionally, queued buses may restrict sight distances for crossing vehicles and pedestrians.

Advantages
  • Eliminates conflicts with right turning vehicles
  • Facilitates bus reentry into the traffic stream
  • Requires shorter deceleration distance
  • Encourages pedestrians to cross behind the bus
Disadvantages
  • Potential for intersection blockage by queued buses
  • Potential for increased rear-end collisions
  • Obstructed sight distances for crossing vehicles and pedestrians
Recommended Uses
  • When near-side traffic is heavier than far-side traffic
  • At intersections with heavy right turn volumes
  • At intersections with transit signal priority

Near-Side Bus Stops

Near-side bus stops are located immediately before an intersection, allowing for passenger unloading and loading while the vehicle is stopped at a red light, preventing double-stopping. When the bus is ready to reenter the traffic stream, the intersection is available to assist in pulling away from the curb and provides the driver with an opportunity to look for oncoming traffic and pedestrians. Near-side stops also allow passengers to board the bus immediately adjacent to the crosswalk, minimizing walk distances.

During peak periods, however, queued buses may block the through lane on the approach to the intersection, potentially disrupting traffic flow. The stop configuration also generates conflicts with right turning vehicles, and delays associated with loading and unloading may lead to unsafe driving in which right turning vehicles drive around the transit vehicle to make a right turn in front of a bus. Additionally, queued buses may restrict sight distances for crossing pedestrians.

Advantages
  • Allows transit drivers to utilize the intersection and available sight distance when pulling away from the curb
  • Provides pedestrian access closest to the crosswalk
Disadvantages
  • Potentially creates double stopping at intersection
  • Generates conflicts with right turning vehicles
  • Potential for through lane blockage by queued buses
  • Obstructs sight lines for crossing pedestrians
  • May result in increased delay to buses and other vehicular traffic
Recommended Uses
  • When far-side traffic is heavier than near-side traffic
  • At intersections with pedestrian safety concerns on the far side

Mid-Block Bus Stops

Mid-block bus stops are located between intersections, which are generally less congested locations than intersection stop locations. As pedestrian crossings are less common at mid-block stops, vehicle and pedestrian sight distance concerns are typically minimized, but the distance passengers must travel between the bus and a protected crosswalk is increased. These stops can be paired with major mid-block generators to reduce walking distances for the majority of transit uses at the stop.

Mid-block stops should generally be used only under special circumstances. However, they increase walking distances for transit users crossing at the nearest intersection, and even encourage illegal mid-block street crossings. Additionally, mid-block stops require both deceleration and acceleration areas, requiring either additional no-parking restrictions or increased turnout construction costs compared intersection stops.

Advantages
  • Less overall traffic congestion
  • Minimized sight distance concerns
  • Ability to directly serve mid-block generators
Disadvantages
  • Encourages unsafe pedestrian crossings
  • Increased walking distances for users crossing the street
  • Increased construction costs or no-parking restrictions
Recommended Uses
  • When there is a major mid-block passenger generator
  • When the interval between adjacent intersections exceeds stop spacing recommendations

On-street Bus Stop Configurations

The design of bus stops has a significant influence on construction costs, parking restrictions, and the impact of transit vehicles on traffic flow characteristics. All stop locations should be examined to determine traffic volumes, traffic speeds, passenger volumes, bus frequencies, bus dwell times, crash patterns, pedestrian and bicycle facilities, roadway geometrics, accessibility, and planned roadway improvements. Types of bus stop designs include bus bays, turnouts, and bulbs.

For bus stop areas, including on-street stops, bus turnouts and terminals, the rigid roadway surface is strongly recommended. This pavement surface has the best potential to retain its shape when exposed to loads and shear forces applied during bus starting and stopping. The pavement should be designed with a minimum 8” portland cement concrete jointed reinforced pavement on a 4” subbase of stabilized granular material. This complies with IDOT’s Bureau of Design Manual. However, if local standards require additional reinforcement, the stronger standards should be used.

Bus Bays

Bus bays consist of a dedicated zone on the side of the roadway for passenger loading and unloading and are commonly created through the restriction of parking and curb-side operations of other vehicles. Bus bays may be used for far-side, near-side, or mid-block stops. All bus bays require a deceleration zone, a stopping zone, and an acceleration zone. Depending on the location of the bus bay, the intersection may serve as the acceleration or deceleration zone. If conflicts with parked vehicles are encountered, bus bays may also be constructed using a ‘closed’ configuration, with a tapered curbs marking the bus stop zone, preventing encroachment by parked vehicles.

Bus bays prevent the need to block a travel lane during passenger loading and unloading. Bus bays have the potential to reduce rear-end collisions as buses pull out of the lane to come to a stop. However, merging back into the travel lane may be challenging during peak hours, increasing the potential for side-swipe or rear-end collisions on reentry. Bus bays also require the restriction of more on street parking. Bus maneuvers at stops may also generate potential conflicts with cyclists when a bicycle lane is provided.

According to IDOT’s Bureau of Local Roads and Streets Manual, bus bays are most effective when:
  • Curb parking is provided
  • The average bus dwell time generally exceeds 30 seconds per stop.
  • Buses expect to layover at the end of the trip.
  • Potential vehicular/bus conflicts warrant the separation of transit and other vehicles.
  • Sight distances prevent traffic from stopping safely behind the bus.

Bus Turnouts

Bus turnouts consist of an entrance taper, a deceleration zone, a stopping zone, an acceleration zone, and an exit taper. They require the curb to be setback to bring the bus vehicle out of the flow of traffic, and can be used only at mid-block.

Bus turnouts do not block a travel lane during passenger loading and unloading and reduce the potential for rear-end collisions by allowing buses to turn out of the travel lane before decelerating ahead of the bus stop. Acceleration distance is provided ahead of the taper to allow the vehicle to merge back into traffic at higher speeds. Curb delineation also helps to guide the bus operator into the bus stop.

Bus turnouts typically have higher construction costs. They rely on otherwise unutilized pavement space for deceleration and acceleration. Bus turnouts remove more potential on-street parking space than bus bulbs, and create potential conflicts with cyclists if on-street bicycle lanes are provided.

Design SpeedEntering SpeedA Suggested Minimum Taper LengthB Minimum Deceleration LengthC Minimum Acceleration Length
30 mph20 mph150'120'50'
35 mph25 mph170'185'250'
40 mph30 mph190'265'400'
45 mph35 mph210'360'700'
50 mph40 mph230'470'975'
Note: L=45’ for each bus that needs to queue in the turnout. (See Section 4a for vehicle characteristics). Source: Bureau of Local Roads and Streets Manual, Special Design Elements, IDOT, pg. 41-4(6), 2008
According to IDOT’s Bureau of Local Roads and Streets Manual, turnouts are most effective when:
  • Street provides arterial service with high speeds.
  • Bus volume is 10 or more during the peak hour.
  • Passenger volume exceeds 20 to 40 boardings per hour.
  • Average bus dwell time exceeds 30 seconds.
  • During peak hour traffic, there are at least 250 vehicles per hour in the curb lane.
  • Buses expect to layover at the end of the trip.
  • Potential vehicular/bus conflicts warrant the separation of transit and other vehicles.
  • There is a history of traffic crashes and/or crashes involving pedestrians.
  • Right-of-way width is sufficient to prevent adverse impacts on pedestrian movements.
  • Curb parking is prohibited.
  • Sight distances prevent traffic from stopping safely behind the bus.
  • Appropriate bus signal priority treatment exists at the intersection.

Bus Bulbs

Bus bulbs are a modified form of curbside stops where the sidewalk extends towards the travel lane, allowing the bus to remain in the rightmost travel lane when picking up and dropping off passengers. Bus bulbs can be used at near-side, far-side, or mid-block locations, and the bulb typically replaces a small section of on-street parking to allow passengers to safety reach the bus.

Bus bulbs eliminate the need for any diverging and merging into the traffic stream, increasing the efficiency with which buses are able to stop, load and unload passengers, and continue. The bus bulb area provides additional space for waiting transit patrons, allowing for additional amenities and better wheelchair access, while removing passengers from pedestrian flow on the sidewalk. When a crosswalk is also provided, bus bulbs decrease the total walking distance for passengers crossing the street.

Bus bulbs require buses to wait within the travel lane while passengers load and unload, potentially generating congestion. Buses stopping in the travel lane may also lead to rear end collisions, or results in unsafe passing maneuvers under congested conditions. Bus bulbs also typically require an infrastructure investment and are more expensive than curbside stops or bus bays with simple parking restriction signs.

Additionally, bus bulbs provide a geometric option for incorporating bicycle lanes through the stop area, reducing potential bus-bike conflicts at stops.

According to IDOT’s Bureau of Local Roads and Streets Manual, bus bulbs are most effective when:
  • Curb parking is provided
  • The street provides arterial service with lower speeds (e.g., posted speeds of 35 mph or less).
  • Bus volumes are 10 or less during the peak hour.
  • Passenger volumes do not exceed 20 boardings an hour.
  • The average bus dwell time is generally less than 30 seconds per stop.
  • During peak hour traffic, there are less than 250 vehicles per hour in the travel lane.
  • Sight distances allow traffic to stop safely behind the bus.

Transit Technologies

Queue Jump & Bypass Lanes

Queue jump and bypass lanes are a geometric form of transit priority in which buses are allowed to use restricted lanes to bypass queued vehicles at signalized intersections, reducing travel time and providing improved service reliability.

A queue jump allows a bus to enter into a short lane, that could also be utilized as a right turn lane, that is located adjacent to the through lane, stopping at the near side of the of the intersection. A separate signal would provide an early green light to the bus to move through the intersection and into the through travel lane prior to the general traffic. Near side bus stop stations are typically used with queue jump lanes.

A bypass lane, which would be adjacent to the through lane, would not have a separate signal, but would continue through the intersection with the general traffic into a receiving lane on the opposite site of the intersection prior to entering into the through lane. Far side stops are typically used with bypass lanes. These are both alternatives to providing mainline transit signal priority.

Several U.S. cities, such as Portland, Denver, San Francisco, Las Vegas and Seattle, have implemented queue jump and bypass lanes into their transit systems.

According to the USDOT Transit Signal Priority Handbook, queue jump lanes provide the greatest benefit in the following situations:
  • Heavy congestion.
  • Existing right turn lanes are available or there is available right-of-way to construct an a lane adjacent to the through lane. Existing roadway shoulders can be utilized if they are wide enough (10-feet minimum) and the pavement is designed to accommodate buses.
  • Relatively low right-turn volume at intersection. High right-turn volumes may conflict with through bus movements and may warrant a separate right turn lane.
  • Implementation of Transit Signal Priority (TSP) in the through lanes would have an unacceptable impact on bus travel times and/or general traffic delay.

Transit Signal Priority (TSP)

Delay from signalized intersections typically accounts for around 10 to 20 percent of all bus delay. A variety of techniques can be implemented at intersections with traffic signals to give transit priority, reduce transit delay, and improve service reliability. These techniques include transit signal priority (TSP).

The report Transit Signal Priority (TSP): A Planning and Implementation Handbook, published by ITS America and funded by the United States Department of Transportation, recommends a systems engineering approach, including:

  • Planning
  • Design
  • Implementation
  • Operations and Maintenance
  • Evaluation, Verification, Validation and Building on TSP

Through this approach Pace will work closely with a number of stakeholders, including IDOT, other DOT's and local jurisdictions, to measure the need for TSP, develop TSP strategies and work through the design and specification process. Usually, traffic signal controllers need to be upgraded to accommodate TSP hardware.

Passive Transit Signal Priority

Passive TSP requires little or no hardware and software investment. In general, when transit operations are predictable with a good understanding of routes, passenger loads, schedule, and/or dwell times, passive priority strategies can be an efficient form of TSP. Timing plans are developed to take into account the operational characteristics of transit service within the corridor, such as the average dwell time at stations. This typically results in a setting the traffic signals to a lower speed in order to accommodate the transit vehicles, which results in more buses arriving at the intersection during a green signal. This system may cause unnecessary delays, stops and frustration for other vehicular traffic within the corridor. Cities that have implemented passive TSP include Washington, D.C., College Station, TX, Ann Arbor MI, and Austin, TX.

Active Transit Signal Priority

Active signal priority refers to a variety of real-time strategies designed to provide priority for a specific transit vehicle approaching an intersection. Active signal priority requires the installation of a detection system to allow transit vehicles to request priority while approaching an intersection and a priority request generator system that is able to handle multiple simultaneous requests and relay the information to the traffic control system. There are two types of active TSP: signal preemption and signal priority. Generally, Pace prefers signal priority because it has less of an impact on normal traffic operations than signal preemption.

Signal Preemption is an emergency system in which the traffic control device terminates normal operation in order to serve the approaching vehicle. The cycle and progression plans are interrupted in order to provide green on the priority approach as quickly as possible. Preemption is common with emergency vehicles and some light rail transit vehicles.

Signal Priority takes into account the time at which the request for priority was made, and modifies the normal signal operation to provide preferential treatment for the vehicle making the priority request without necessarily disrupting operations.

Common types of priority timing plan modifications include green extension (extending the green time for the priority movement to allow the approaching vehicle to continue without stopping), early green (shortening the preceding phases to minimize red time on the priority approach), phase insertion (inserting a special priority phase into the normal signal sequence), and phase rotation (modifying the order of signal phases).

Signal priority requires a more sophisticated controller system that is able to compare the time of the request to the real-time signal phasing. More advanced signal systems combined with real-time traffic detection systems allow for adaptive signal priority strategies, that assess real-time conditions based on a number of performance criteria, such as person, transit, or vehicle delay, and implement timing plans optimized based on the current state of the system.

Bus Stop Location and Roadway Design Implementation Checklist

Guideline PrinciplesImplementation Tools
Working closely with Pace, determine the appropriate location for transit stops and facilities based on local conditions.Local public works/engineering standards, D.O.T standards
To the extent possible, use rigid roadway surfaces at bus stops, bus turnouts, and transit terminals.Local public works/engineering standards, D.O.T standards
Utilize appropriate bus bay configurations to ensure efficient bus service on busy streets.Local public works/engineering standards, D.O.T standards
Coordinate with Pace to implement suitable transit technologies (such as queue jumps and transit signal priority) when roadway geometry and traffic conditions permitLocal public works/engineering standards, D.O.T standards

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