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84 The Green Book indicates that the design of every roadway project should consider the needs of all travel modes: automobiles, bicycles, pedestrians, transit, and trucks (AASHTO 2018). This does not necessarily mean that facilities for every mode are provided as part of every project, but rather that the appropriate balance among the needs of each mode be sought for every project. The appropriate balance will vary between corridors and projects, and corridor-specific and project-specific priorities should be assigned. This Guide has dealt extensively with automobile and truck considerations, and has discussed truck considerations with respect to pedestrians, bicyclists, and transit where appropriate. This chapter summarizes the key issues in balancing truck considerations with the needs of pedestrians, bicyclists, and transit. 5.1 Pedestrian Considerations An appropriate balance between the needs of trucks and pedestrians should be sought for every project where both trucks and pedestrians are present. Rural projects on truck routes often serve corridors where pedestrian travel is minimal, and there may be substantial flexibility to design roadways and intersections to accommodate trucks. Even where design for trucks generally has priority, specific consideration should be given to school zones and school bus stops where students should be provided with a safe route between the school, the bus stop, and their homes. This may include consideration of advisory speed signing, bus stop signing, and marked crosswalks where appropriate. At the other extreme, the needs of pedestrians should generally be assigned priority over trucks in the design of collector and local streets, particularly in urban areas. Pedestrian volumes are often medium to high, indicating a need for sidewalks and crosswalks designed with limited crossing distances. Truck volumes are typically low on urban collector and local streets and, even where they are not, trucks generally need to travel only short distances to reach an arterial street where design for trucks may be assigned a higher priority. The greatest challenges in balancing the needs of trucks and pedestrians occur on urban arterials and on extensions of rural highways through small towns. In these areas, the demands for both truck and pedestrian travel are likely to be high, and there are definite tradeoffs in design for trucks and pedestrians that need to be addressed. The most satisfactory solutions can be achieved where truck and pedestrian movements can be separated in space, so that they do not conflict. Less satisfactory, but still desirable, solutions can be achieved where truck and pedestrian movements can be separated in time, as with the use of exclusive pedestrian phases at signal- ized intersections. Where truck and pedestrian movements cannot be separated in space or time, design decisions should be made on a case-by-case basis considering truck and pedestrian demand volumes and consistency within corridors. C H A P T E R 5 Balancing Truck Considerations with Other Modes
Balancing Truck Considerations with Other Modes 85 A key to achieving the appropriate balance between the infrastructure and operational needs of trucks and pedestrians is appropriate corridor planning identifying particular corridors as priorities for truck movements and other corridors as priorities for pedestrian movements (see Section 3.1 on Planning). Most corridors will always serve a mix of truck and pedestrian demand volumes, but good planning can identify which mode should be assigned priority in design and operations of particular corridors. Key design considerations for truck routes and other corridors where both truck and pedestrian movements are present include the following: â¢ Provide sidewalks on both sides of the road to facilitate pedestrian movements along the corridor separated from the traveled way that serves truck as well as other motor vehicle movements. â¢ Provide marked crosswalks as extensions of the sidewalk at intersections. â¢ Establish truck routes that avoid existing or anticipated high-volume pedestrian corridors where possible, keeping in mind that limited amounts of out-of-direction travel are more tolerable to motor vehicle drivers than to pedestrians. â¢ Provide medians on multilane roadways to create an opportunity for two-stage pedestrian crossing maneuvers that minimize pedestrian crossing distances. â¢ Provide short curb return radii for right turns that minimize pedestrian crossing distances except where truck right-turn volumes are substantial. â¢ Route truck and pedestrian movements on different paths through major intersections where feasible. Figure 52 illustrates how crosswalks can create a pedestrian path through an at-grade intersection that minimizes conflict with a high truck movement. â¢ Provide channelized right-turn roadways for high-volume right-turn movements by trucks. This design provides a large curb return radius to facilitate right turns by trucks. Pedestrians cross the right-turn roadway and the main roadway in separate movements, which should minimize pedestrian crossing distances. The major disadvantage of this design is for pedestrians with vision disabilities who may have difficulty determining the correct path for crossing the channelized right-turn roadway. For additional guidance on roadway and intersection design to accommodate pedestrians, see the AASHTO Guide for the Planning, Design, and Operation of Pedestrian Facilities (AASHTO 2004). 5.2 Bicycle Considerations Similar to the previous discussion of pedestrians, an appropriate balance between the needs of trucks and bicyclists should be sought for every project where both trucks and bicyclists are present. Bicycle travel on rural truck routes may be minimal, and there may be substantial flexibility to design roadways and intersections to accommodate trucks. However, in urban areas, the needs of bicyclists should be given higher priority over trucks in the design of collector and local streets. Truck volumes are typically low on urban collector and local streets and, even where they are not, trucks generally need to travel only short distances to reach an arterial street where design for trucks may be assigned a higher priority. Where bicycle facilities are provided along a truck route, the bicycle facilities should be designed to minimize conflicts between bicycles and trucks or other vehicles. This may be accomplished by the following: â¢ Providing an off-road bicycle path or shared-use path. â¢ Providing a buffer to separate on-road bicycle lanes from adjacent travel lanes to accommodate greater separation between bicycles and trucks.
86 Design and Access Management Guidelines for Truck Routes: Planning and Design Guide â¢ Providing wider lanes, especially wider curb lanes, to accommodate greater separation between bicycles and trucks. The greatest challenges in balancing the needs of trucks and bicyclists occur on urban arterials and on extensions of rural highways through small towns. In these areas, there are definite trade offs in design for trucks and bicyclists that need to be addressed. Where bicycle volumes are medium to high, an on-road bike lane is one of several types of bicycle facilities that may be appropriate (see previous list). While this solution is desirable in that it physically separates truck and bicycle movements, coordination is needed between the transportation agency, trucking companies, and businesses so that the bike lane is strategically placed in a location that minimizes conflict with trucks parking for deliveries. In some cases, such as one-way streets, this may be as straightforward as locating the bike lane on the other side of the street. Where truck and bicycle movements cannot be separated in space or time, design decisions should be made on a case-by- case basis considering truck and bicycle demand volumes and consistency within corridors. A key to achieving the appropriate balance between trucks and bicyclists is appropriate corridor planning identifying particular corridors as priorities for truck movements and other corridors as priorities for bicycle movements (see Section 3.1 on Planning). Some corridors will always serve a mix of truck and bicycle demand volumes, but good planning can identify which mode should be assigned priority in design and operations of particular corridors. Figure 52. Separation of truck and pedestrian movements through an intersection.
Balancing Truck Considerations with Other Modes 87 Key design considerations for truck routes and other corridors where both truck and bicycle movements are present include the following: â¢ When locating bicycle routes, avoid industrial areas (e.g., UPS entrances). â¢ Establish truck routes that avoid high-volume bicycle corridors where possible, keeping in mind that limited amounts of out-of-direction travel are more tolerable to motor vehicle drivers than to bicyclists. â¢ Place bike lanes in locations with minimal truck parking for deliveries. â¢ Place bike lanes away from wide driveways to reduce bicyclist exposure to motor vehicles entering or exiting. â¢ Improve shoulders where bicyclists are prevalent or where the corridor has destinations likely to be accessed by bicyclists. For additional guidance on roadway and intersection design to accommodate bicyclists, see the AASHTO Guide for the Development of Bicycle Facilities (AASHTO 2012). 5.3 Transit Considerations Where transit is present on a truck route, planning for bus stops and transit station locations should take into account adjacent truck access points on the truck route. For light rail transit stations placed in the median of a truck facility, stations should be placed out of the path of turning trucks to prohibit trucks from turning onto the facility at that access point, and an alternative route should be provided to an access point at which the turning path of the truck can be accommodated. Truck routes that also serve as transit routes, including buses or light rail, inherently must accom- modate pedestrians. Care should be taken, especially in industrial areas where workers use public transportation, to design truck facilities that can also accommodate pedestrians accessing adjacent areas and developments. It is recommended to separate trucks and pedestrians in space or in time as much as possible to minimize conflicts between pedestrians and trucks (see Section 5.1). Case Study: Positioning Light Rail Stations to Avoid Conflicts with Turning Trucks An MPO noted that truck movements were one key consideration in choosing station locations for a recent light rail project. Stations were purposely located away from intersections of the light rail tracks with truck routes to avoid truck- pedestrian conflicts. (Photo source: Google Earth.)