Vehicle, Service & Roadway

In order to balance safe and efficient operation of transit with general traffic flow, it is important to consider transit vehicle measurements and operational characteristics when designing roadways, intersections, and transit facilities that will be used by Pace vehicles. Proper design minimizes transit vehicle encroachment into other lanes of traffic, decreases property and vehicle damage, reduces travel times, improves passenger comfort and safety, and helps maintain pavement surfaces.

Vehicle Specifications

Pace offers a variety of both fixed and variable-routes service, using a wide range of vehicle types. For flexible route services, such as Dial-a-Ride, Paratransit, and Call-n-Ride services, Pace operates a fleet of vehicles ranging in size from vans to 30-foot Paratransit buses.

All fixed-route services use buses that are 30-feet or longer, and vehicle size is directly related to the type of service provided.

Pace recommends that, whenever possible, shoulder widths, pavement design, curbs, building overhangs, clearance areas, vehicle stop area dimensions, and turning radii on all bus routes should be designed to accommodate the specific type of vehicle serving the route, or that may serve the route in the future. Local entities should consult with Pace when designing infrastructure to determine the anticipated future service and vehicle types to be used in a given location.

The table below describes the assumed dimensions of various types of Pace vehicles.

DimensionConnectorLocal BusExpress Bus/ART
Length with bumpers-40.7'-
Width with mirrors-10.0’-
Front Overhang-7.0’-
Rear Overhang-8.0’-
Ground Clearance-11’’-
Transit Rolling Stock

Transit vehicles vary in size and maneuverability, and local infrastructure should be designed to respond to specific transit operations and rolling stock characteristics.

Vehicle Turning Radius

To accommodate Local, Express and ART buses, Pace recommends designing for a minimum 50-foot outside turning clearance at all locations where Pace vehicles turn. The 50-foot design radius meets Pace’s vehicle turning needs under ideal operating conditions. Minimum clearances are generally sufficient for ideal conditions at speeds of less than 10 miles per hour. Other turning radii may apply based on different intended travel speeds, vehicle dimenions, turning characteristics, levels of traffic congestion, sight lines, and snow accumulation. Manufacturer specifications, transportation engineering standards, and/or the Pace Transportation Engineer should be consulted for more specific information.

Streets and on-site circulation should accommodate Pace vehicles based on specific service provisions.

Roadway Geometrics

When transit service is planned or anticipated along a corridor, it is important to consider bus design and operation characteristics in roadway design. Anticipated vehicle speeds, traffic volume, on-street parking conditions and intersection turning radii are factors that should be considered when designing a roadway or off-street facility that will be serviced by Pace transit vehicles. This section includes a menu of potential roadway elements specifically related to transit. Pace planning and engineering staff should be contacted to assist in determining which elements are appropriate or necessary based on transit service and local traffic characteristics. Generally, design standards for these elements meet or exceed IDOT standards.

Lane Widths

For all roadways that accommodate transit vehicles, Pace recommends a 12-foot lane width (minimum) for the curb lane to insure proper maneuverability of its vehicles. However, in areas with constrained right-of-way or high levels of pedestrian crossing activity, 11-foot lanes may be used. Refer to IDOT’s Bureau of Local Roads and Streets Manual for information regarding variations in lane width.


Pace recommends minimal grades to the extent possible for roadways serviced by Pace vehicles. Also, changes in grade should be gradual so that buses can easily negotiate changes with adequate ground clearance to promote passenger comfort. At station locations, the roadway profile should be less than 5% in order to meet the requirements the requirements of the Americans with Disabilities Act (ADA) Accessibility Guidelines.

Roadway Pavement

To insure that local municipal standards are adequate for transit service, Pace recommends that pavement be constructed to handle vehicles with loads of 20,000 lbs. per axle . Both rigid (concrete) and flexible (asphalt) pavement designs may be used for roadways, driveway aprons, access aisles, bus stop areas and other locations where heavy bus use is anticipated.

For bus stop areas, including bus bays, bus turnouts, bus bulbs and terminals, rigid pavement design is strongly recommended . Due to loads and shear forces applied to pavement surfaces during bus starting and stopping movements, a rigid pavement surface has the best potential to retain its shape. The pavement should be designed to conform to IDOT standards for Class II roadways. However, if local requirements exceed these standards for commercial and industrial driveways or parking areas, the local standard should be followed.

Curbside Boarding Area

Pace’s vision for regional suburban bus service includes a seamless transition from the sidewalk to the bus stop and to the transit vehicle. In essence, Pace aims to create a service that is a “sidewalk on wheels,” in which riders experience a comfortable, accessible and efficient trip from start to finish. The design of the curbside stop, and the curb itself, will have an impact on how comprehensively Pace can implement its vision. While the specific vehicle characteristics are yet to be determined, engineers and designers should consider to critical service concepts that influence the design of the roadway/bus stop interface.

Level Boarding entails sidewalk and curb infrastructure that brings the rider to the same elevation as the floor of the bus at the point of boarding. This makes for more efficient boarding for all passengers, but especially those reliant upon wheelchairs, strollers, and other assisted transport.

Precision Docking is the integration of transit technology and infrastructure that enables a vehicle to dock at a specific point that minimizes distance from the curb and properly aligns the bus with curbside infrastructure. This enables focused design solutions at specific locations that result in a better transit experience for operators and riders.

Bicycle Lanes

Clearly marked bicycle paths and bicycle boulevards have the potential to significantly increase the catchment area of a bus stop as individuals will generally bike three to four times as far as they will walk to a bus stop. When a dedicated bicycle lane is provided on the curbside of the right most lane, dotted lines should be provided at the entrance to the bus stop area to indicate to cyclists that a bus may be entering their lane, as described in Section 9C.04 of the Manual on Uniform Traffic Control Devices (MUTCD, 2009).

Additional information on the planning and design of bicycle facilities can be found in Chapter 42 of the Illinois Bureau of Local Roads and Streets Manual (IDOT, 2005) as well as AASHTO’s Guide for the Development of Bicycle Facilities (AASHTO, 2012).

Vehicle, Service & Roadway Implementation Checklist

Guideline PrinciplesImplementation Tools
Design standards are used that reflect specific transit vehicles to be used in the development area.Local subdivision regulations, local public works/engineering standards, D.O.T standards
Design for appropriate outside turning clearance at all locations where Pace vehicles operate.Local public works/engineering standards, D.O.T standards
For all roadways that accommodate transit operations, appropriate lane widths are used to ensure proper maneuverability of transit vehicles.Local zoning and subdivision regulations, local public works/engineering standards, D.O.T standards
Design minimal grades to the extent possible for roadways serviced by Pace vehicles and comply with ADA standards at stations and throughout the pedestrian network.Local public works/engineering standards, D.O.T standards
Pavement should be designed to handle anticipated vehicle loads.Local public works/engineering standards, D.O.T standards
Consider the long-term implementation of level boarding and precision docking when engineering bus stop areas.Local public works/engineering standards, D.O.T standards
Use appropriate lane markers to differentiate between transit areas, bicycle lanes, on-street parking, etc.Local public works/engineering standards, D.O.T standards