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26 Modal Considerations and Accommodation The following sections discuss issues associated with users and present design considerations for each mode in order to achieve a contextual design solution. The Expanded FCS matrix is also presented along with considerations for transit and freight overlays. Driver Accommodation The metrics used to define the contextâroadway interaction for drivers are the target operating speed and the balance between mobility and access. Target Operating Speed Target operating speed is grouped into three categories: low (<30 mph), medium (30â45 mph), and high (>45 mph). These definitions coincide, in general, with the existing high and low design speed concepts in A Policy on Geometric Design of Highways and Streets (AASHTO 2011), or Green Book, and can form the basis for initial designs. Speed, in general, decreases along the context continuum (from rural to urban core) as well as along the roadway type (from principal arterials to locals). The speed used in the Expanded FCS is the target operating speed of the roadway. The rationale for selecting operating speed in the Expanded FCS is the need to recognize the influence of driver desire and expectations. Moreover, the goal is to develop a facility where the operating speed is close to the design speed, resulting in an environment with smaller speed differences among drivers. Smaller speed differences could improve safety, because they will eliminate discrepancies between design speed and operating speeds, creating a more uniform speed profile among drivers. These speeds need to be considered with both existing and future volumes and contexts. The limits for each category are based on established practices and extensive research. The speed of 25 mph is considered the upper limit for the low-speed environments based on current trends of several urban areas to facilitate a speed limit of 25 mph. Note that 20 mph is considered the survivability speed for pedestrians and bicyclists in the event of a collision with a vehicle. Such collisions typically result in injuries, but non-drivers have a high chance of surviving when speeds remain at or below 20 mph. As such, speeds of 20 mph or less should be considered in areas of higher pedestrian activity in the urban and urban core environments. Target speeds for urban and rural towns have been designated as low/medium because of the competing issues within these contexts and the varied pedestrian and roadside environment. The designer should examine the available speed range to select the operating speed most appropriate for all users given the facilities and context. The lower limit for high speeds is based on the Green Book defi- nition of high-speed roads, which are those with speeds of 50 mph and above.
Modal Considerations and Accommodation 27 Access and Mobility The typical tradeoff between access and mobility presented in the existing classification system is enhanced in the Expanded FCS to reflect the influence of roadway and context as they change across the various matrix categories. Access is defined as the frequency of driveways or intersections and is grouped in three categories based on distance between access points: low (>0.75 mile), medium (0.75â0.25 mile); and high (<0.25 mile). Mobility is definedâqualitativelyâas a function conges- tion level: low (congested conditions), medium (some congestion), and high (no congestion; free flow). Volumes referred to here are during the peak period. The values for the access are based on current understanding of access management concepts and principles. While it is desirable for access density to decrease on higher mobility roadways, within certain contexts, this rule does not hold true, as when the roadway serves as the primary means of access. Mobility levels are based on generalized concepts of the level of service (LOS) for a facility and correspond to broad values of all roadways. Expanded FCS Matrix Approach For the driver, the interaction of access and mobility varies along the context continuum: mobility decreases from rural to urban core and access increases from rural to urban core. Figure 17 shows an example for principal arterials. In a rural setting, the mobility is expected to be high with low congestion levels, while access may be low with few driveways or intersections along the corridor. As the context settings change with increased density and smaller building setbacks as well as pedestrian volumes, mobility declines (i.e., more congestion is anticipated) and access increases, which provides more opportunities to access land uses (which also change from rural character to a more developed environment). The target operating speed also changes along the context continuum, with higher speeds anticipated in rural settings. This reflects the higher mobility in these locations. Reductions in operating speed are anticipated as the context transitions to developed and urban settings. Similar changes are also noted along the roadway-type continuum. Mobility decreases (from principal arterial to local roads), while access increases along the same direction. Fig- ure 18 illustrates this concept for rural settings. Mobility increases as the roadway type rises in category, reflecting the anticipated higher mobility levels of arterials compared to local roads. In a reverse manner, access levels increase as the roadway type decreases in category, reflecting H = high, M = medium, L = low Figure 17. Interaction of metrics for Expanded FCS matrix along context continuum.
28 An Expanded Functional Classification System for Highways and Streets the greater need for access for local roads. The target speed also changes among the categories, with an increasing trend from local to arterial roads. This reflects the mobility trends previously noted. The changes along both axes of the matrix enable a three-dimensional interpretation of the typical accessâmobility graph used in the existing functional classification system. Note that speed is less of a factor in mobility for urban areas than for rural areas. Satisfactory mobility/ capacity may be maintained in urban areas even at low speeds. This has the additional benefit of decreasing injuries for vulnerable users. A summary of the complete interactions and relationships for drivers is shown in Figure 19. The matrix indicates how driver metrics change based on the interactions of different combinations of context and roadway. The product is a three-dimensional representation of the effects of access, mobility, and speed. H = high, M = medium, L = low Figure 18. Interaction of metrics for Expanded FCS matrix along roadway continuum. H = high, M = medium, L = low Figure 19. Expanded FCS driver interaction matrix.
Modal Considerations and Accommodation 29 Design Considerations The primary design characteristic for drivers is mobility. However, because roadways may have other modal traffic, the level and type of separation from vehicles provided for the other users may also need to be considered. These considerations should be based on the volumes of motorized, pedestrian, and bicycle traffic. Increased separation may be needed between high volumes of other users and motorized traffic. This can be achieved using either barriers or with separate facilities. Additional discussion on separation is provided with the discussions of other modes. Another issue to consider is that not all routes are conducive to bicyclists and pedestrians (i.e., high-speed principal arterials). In such cases, alternative routes should be identified that could satisfy the mobility needs of these users and accommodate them as needed. However, in some restricted cases, speeds must be reduced or varied to accommodate specific users more safely. For principal and minor arterials in rural town and urban contexts, designers can select from a wider range of speed choices (low though medium) to accommodate pedestrian and bicyclist demands and provide for a safe design for all users. Bicyclist Accommodation This section of the guidance presents the concepts underlying the treatment of bicyclists in the bicycle facilities classifications in the Expanded FCS. The primary consideration for a bicycle facility is the level of separation between motorized and bicycle traffic. Other factors that can help determine the proper treatment of bicyclists are discussed as well. Separation Bicycle facilities can be generally categorized based on the amount of separation they provide from motorized traffic. For the purposes of the Expanded FCS, bicycle facilities are categorized as follows: â¢ High separationâprovides physical separation from traffic in the form of physical barrier or lateral buffer. â¢ Medium separationâprovides a dedicated space adjacent to motorized traffic. â¢ Low/No separationâprovides joint-use facilities for motorized and non-motorized traffic. The amount of separation necessary for a facility is dependent mostly on the following: â¢ The amount of bicycle traffic on the facility. â¢ The speed of motorized traffic on the adjacent roadway. â¢ The amount of motorized traffic on the adjacent roadway. The need for variances in separation may be demonstrated by examining two extreme exam- ples. First, consider a high-speed urban arterial that also serves as a regional bicycle connection; it has a heavy volume of bicycle traffic. In this instance, a cycle track or even independent multi- use path may be appropriate to serve the bicycle traffic. Providing a separate facility reduces the number of conflicts between the two modes of traffic, which may be frequent considering the high traffic volumes of both modes as well as the potential severity of conflicts due to high speeds of the motorized facility. Conversely, at a low-speed neighborhood street serving only local riders, bicycles and vehicles may share the same space because of the low probability of conflict and low speed differences between the two modes.
30 An Expanded Functional Classification System for Highways and Streets The Expanded FCS matrix identifies a proposed level of separation that may be considered for each bicycle facility category according to roadway type and context. Potential treatments that may be included within each of these separation levels are as follows: â¢ Low/No-separation treatments â No specific treatment, for cases with rare or occasional bicycle traffic. â Sharrowsâfor cases when a bicycle lane is not feasible and they can be used with narrow lanes, ensuring that a driver cannot pass a cyclist except very slowly. â¢ Medium-separation treatments â Bike lanesâfor separating bicycles from vehicular traffic. â¢ High-separation treatments â Buffered bike lane/cycle trackâfor cases with high bicycle volume. â Multi-use pathâfor cases with high bicycle and pedestrian traffic. Expanded FCS Matrix Approach The level of separation provided should be based on speed of traffic, context, and road- way type, and is defined for all three levels of bicycle traffic. The separation changes along the context continuum to reflect the effects of target operating speed. For example, higher speeds on principal arterials require some balancing of the separation to be provided based on the amount of anticipated bicycle traffic and context. For rural and suburban contexts, high bicycle volumes require high separation and the designer should determine the type to be used based on the discussion provided in the next Design Considerations section. In all other contexts with lower speeds, a medium separation is recommended for high-volume traffic (Figure 20). Similarly, there are interactions between bicycle separation and roadway type. For example, on local roads, the slow-moving traffic does not require any special separation for bicyclists; therefore, for all bicycle facility classes, low separation is recommended (Figure 21). The complete interaction of the roadway type, context, and bicycle separation is shown in Figure 22. All options are provided to allow for the designer to determine the appropriate facility required to accommodate bicycle traffic based on the bicycle facility classifications that may exist. The matrix presents the minimum accommodation that should be expected for travelers of all modes. However, these levels of accommodation may be increased to address local priorities and where sufficient space exists to provide enhancements. Bicycle facility class: CC = citywide connector, NC = neighborhood connector, LC = local connector Separation level: H = high, M = medium, L = low Figure 20. Interaction of bicycle separation levels by context in Expanded FCS matrix.
Modal Considerations and Accommodation 31 Bicycle facility class: CC = citywide connector, NC = neighborhood connector, LC = local connector Separation level: H = high, M = medium, L = low Figure 22. Expanded FCS bicyclist interaction matrix. Figure 21. Interaction of bicycle separation levels by roadway type in the Expanded FCS matrix. Bicycle facility class: CC = citywide connector, NC = neighborhood connector, LC = local connector Separation level: H = high, M = medium, L = low
32 An Expanded Functional Classification System for Highways and Streets Design Considerations Sharrows with narrow lanes may be used when the narrow lane would not cause safety con- cerns or exceptionally delay traffic flow, including in the following cases: â¢ Small speed differences between bicycles and vehicles. â¢ Low volume of vehicular or bicycle traffic. â¢ Short-length bicycle facilities (<0.25 miles). Sharrows with narrow lanes are no more than 10 feet wide and traffic speeds are low (less than 20 mph). Conversely, sharrows with wider lanes typically provide a wide travel lane of 13â14 feet with supplemental striping and/or signing. The wider lane allows for vehicular traffic to cau- tiously pass slower bicycle traffic. It may be a solution for constrained roadways with minimal speed differences between bicycle and vehicular traffic (<30 mph). Bike lanes, while providing space exclusive from motorized vehicle travel lanes, do not provide physical separation. Bicycleâvehicular conflicts at intersections with turning traffic and from opening-door incidents with parked vehicles are not eliminated. Narrower bike lanes (â¼4 feet) should be used only when right-of-way is constrained and not in the presence of on-street park- ing, unless an additional buffer is provided. Additionally, narrower bike lanes should not be used for high-speed facilities and/or facilities with a combination of high volumes of vehicular and bicycle traffic. In the presence of higher-speed traffic or high traffic volumes, wider bike lanes are warranted to create additional separation between facilities. Off-street paths (and trails) are cycle routes that are not part of the regular street network. An ancillary consideration is the separation of bicyclists from pedestrian activities. Separation of bicyclists from both motorized vehicles and pedestrians should be based on the volume of autos/pedestrian traffic and bicycle traffic as well as the anticipated speed of bicyclists and autos. Vehicular speed should be targeted based on the functional classification and context of the roadway. In addition, bicycle speed may fluctuate based on whether the roadway has been des- ignated for FHWA âDesign Bicyclistâ Group A, B, or C (advanced, basic, or children bicyclists, respectively; FHWA 1992). Bicycle separation is highly contingent on the difference between bicycle speed and motor- ized traffic speed. As speeds go up, as indicated in the matrix (Figure 22), separation should also increase. However, if lower volumes of bicycle traffic are anticipated and more bicycle commuting traffic is anticipated, higher bicycle speeds (and possibly increased comfort riding in traffic) may be assumed, allowing reduced separation. If conflicts arise and vehicular or bicycle traffic cannot be accommodated on parallel routes, lower target speeds and roadway design (e.g., narrower lanes, lowered mobility) to achieve them should be considered, in lieu of increased separation. While bicycle facilities are aligned to fit well with the overall vehicular functional classifica- tion, bicycle facilities should be considered in terms of the overall bicycle network. The overall bicycle network should be planned to allow connections to recreational cycling areas for casual users (Group B or C) and provide commuting and general transportation opportunities for Group A users. While it would be beneficial to develop a formal area-wide bicycle network that can be overlaid with vehicular, pedestrian, and transit uses, it is not necessary as long as network connectivity is considered on a project-by-project basis. Bicycle facilities can be considered longitudinal treatments along the length of the roadway, and limited intersection elements may be required. However, considerations for turns for pri- mary junctions within the bicycle network should be incorporated into the plan such as the use of bike boxes. The AASHTO Guide for the Development of Bicycle Facilities (AASHTO 2012) and the National Association of City Transportation Officials (NACTO) Urban Bikeway Design Guide (NACTO 2011) address bicycle design for specific intersection issues.
Modal Considerations and Accommodation 33 Access density is also a consideration with bicycles, especially with cycle tracks and buffered bike lanes. In areas of high access density, the separation of bicycle traffic should be avoided because it increases the number of crossing conflicts for ingress and egress traffic. Rural bicycle facilities also necessitate additional consideration in the design process. As noted previously, bicycle networks are more prevalent within urbanized areas because of the increased density, allowing the shorter range of cycling to be a more effective transportation solution. However, rural areas may experience high volumes in special circumstances, often arising from high demands from recreational riders. Understanding the unique and varying needs of rec- reational bicyclists is important in understanding the final design of the facility. For instance, routes that have a high level of use by bicycle club riders may be used by experienced riders comfortable riding next to or sharing lanes with higher-speed traffic, while recreational facili- ties surrounding parks or other attractions may be used by riders of all abilities and necessitate higher-separation facilities due to high vehicular speeds. Pedestrian Accommodation This section of the guidance presents the concepts underlying the treatment of pedestrians in the Expanded FCS. The primary consideration of a pedestrian facility is its width. Other factors that can help determine the proper treatment of pedestrians are also discussed. Facility Width Pedestrian facilities can be generally categorized by their width. For the purposes of this document, they are categorized as follows: â¢ *âno facilities for pedestrians, except for occasional site-specific facilities. â¢ Minimum widthâthe minimum required width based on ADA requirements. â¢ Wide widthâwider than minimum required width for a pedestrian facility. â¢ Enhanced widthâmore space than the wide width in order to accommodate congregating groups of pedestrians and street furniture. The first category [noted with an asterisk (*)] indicates that, for occasional pedestrians to be accommodated, the site-specific conditions and future plans for the area must be examined to determine whether facilities may be placed or alternative accommodations such as shoulders for pedestrian/bicycle use should be considered. In addition to the facility width, separation of the pedestrian facility from the travel way is also an important consideration. However, this design element is primarily dependent on the target operating speed of the automobile facility rather than on the level of activity on the facility. Typi- cally, medium- and high-speed facilities will require separation from the travel way whether in the form of a landscaped buffer, bicycle lanes, or parking areas. For low-speed facilities, the sidewalk may be attached to the curb, directly adjacent to the travel way without a need for a buffer area. The width necessary for a pedestrian facility depends on many factors, but most notably on the following: â¢ The amount of pedestrian traffic adjacent to the roadway. â¢ The speed of motorized traffic on the adjacent roadway and required separation. â¢ The amount of motorized traffic on the adjacent roadway. The absence of physical separation between a sidewalk and the travel way may reduce the avail- able functional width of the sidewalk in areas of high-speed and high-volume traffic because pedes- trians shy away from the edge of the roadway. Therefore, the final design of the facility should ensure both proper width and separation to meet the anticipated needs of pedestrians within a corridor.
34 An Expanded Functional Classification System for Highways and Streets The need for variations in width may be demonstrated by examining two extreme examples. First, consider a high-speed urban arterial that also serves as a connector between large centers of activity (e.g., a university campus and the downtown area) that have heavy volumes of pedestrian traffic. In this instance, a wide- or enhanced-width detached facility may be appropriate to serve the pedestrian traffic. Providing a separation improves pedestriansâ comfort levels and could reduce the number of conflicts between the two modes, which may be frequent given the high traffic volumes of both facilities, and the potential severity of conflicts due to the high speeds of the motorized facility. Conversely, on a low-speed local street serving only local pedestrians, a minimum- or wide-width attached facility may be appropriate, depending on the pedestrian volumes, in order to decrease the probability of conflicts. The proposed functional classification matrix identifies a proposed level of facility width that may be considered for each pedestrian facility category according to roadway type and context. The following section identifies potential treatments that may be included within each of these width ranges. Expanded FCS Matrix Approach The width of the pedestrian facility is defined for the anticipated or potential levels of pedes- trian traffic for each context and roadway type; the separation of the pedestrian facility from the travel way is based on the speed of the motorized traffic. The width changes along the context continuum to reflect the traffic volumes anticipated for the facility. For example, design of princi- pal arterials in high-speed environments needs to consider the pedestrian traffic volumes in order to determine the appropriate width. In this case, for rural and suburban contexts, high pedes- trian volumes require wide width (which here can be viewed as a separate facility) to establish a safe pedestrian environment, while in cases where pedestrians are present rarely or occasionally, whether to add pedestrian facilities requires additional consideration and appropriate facilities need to be included commensurate with pedestrian volumes. Similar considerations are devel- oped for the other contexts with lower speeds where the anticipated pedestrian volumes would indicate the width to be provided (Figure 23). There is no interaction between pedestrian facilities and roadway, because the designed facility width will depend on the level of pedestrian traffic. However, as previously noted, medium- and Pedestrian traffic levels: P1 = rare/occasional, P2 = low, P3 = medium, P4 = high Pedestrian facility width: * = site specific, Min = minimum, Wide = greater than minimum, Enhanced = wide for large congregating pedestrian groups Pedestrian facility separation should be considered in conjunction with driver target speeds. Figure 23. Interaction of pedestrian separation levels by context in Expanded FCS matrix.
Modal Considerations and Accommodation 35 high-speed roadways do require increased separation of pedestrian facilities and the travel way of the road. The complete interaction of the Expanded FCS matrix and pedestrian facility width is shown in Figure 24. The matrix presents the minimum accommodation that should be expected for travelers of all modes. However, these levels of accommodation may be increased to address local priorities and where sufficient space exists to provide enhancements. Design Considerations The primary design characteristic of pedestrian facilities is the width of the sidewalk or path that can comfortably accommodate the demand in a given context. Pedestrian facility widths are defined as minimum per ADA requirements. This width has the ability to accommodate a high demand of pedestrians allowing for walking single file in each direction. In higher-density areas, pedestrians may walk several across or in larger queues, which requires wider sidewalks to accommodate the higher volumes of pedestrian traffic. In the most active pedestrian centers, sidewalks can serve as not only walking routes, but also places where people congregate. In these contexts, enhanced and wider sidewalks are necessary to not only accommodate pedestrian groups, but also provide for activity areas and street furniture, such as waiting areas, benches, or even outdoor seating, depending upon the adjacent land use. An ancillary design consideration for pedestrian facilities is whether to increase separation from motorized (and bike) traffic when medium or high speeds or volumes could expose pedes- trians to risk or deter them from walking because they may feel uncomfortable or unsafe. In these instances, a buffer between the traffic and the pedestrians is desirable. Buffer widths vary depending on land uses, and different types of buffers can be used to create an inviting pedes- trian environment. On-street parking or bicycle lanes can also act as buffer. Desirable widths vary from 2â4 feet for local and collector roadways to 5â6 feet for arterials (AASHTO 2004b). Pedestrian traffic levels: P1 = rare/occasional, P2 = low, P3 = medium, P4 = high Pedestrian facility width: * = site specific, Min = minimum, Wide = greater than minimum, Enhanced = wide for large congregating pedestrian groups Pedestrian facility separation should be considered in conjunction with driver target speeds. Figure 24. Expanded FCS pedestrian interaction matrix.
36 An Expanded Functional Classification System for Highways and Streets Increased tree lawns, shielding, or physical separations could be used as buffers, and, in extreme cases, off-roadway paths may provide the best pedestrian experience. To determine the pedes- trian LOS when buffers are used, the designer needs to take into account the reduction to the effective facility width due to the presence of the separation (e.g., trees, shrubs, or grass) based on the approach and values outlined in the Highway Capacity Manual (TRB 2016). Intersections are of particular concern to pedestrians. As such, nodal treatments and provision of appropriate pedestrian-crossing treatments are critical. Where possible, for high pedestrian movement, narrow crossing widths should be used. Crossing widths can be minimized through tighter intersection curb radii and minimizing the number of lanes to be crossed. These treat- ments may conflict with vehicular demands, which prioritize mobility (which requires more lanes) or transit and freight routes (which may require wider turning radii). Consideration may be given to alternative guidance for auxiliary turn lanes that coexist with bicycle and pedestrian traffic. Design should take into account the increased exposure and risk to other modes in the presence of auxiliary turn lanes (which increase crossing distance and encourage bicycle con- flicts) in light of any decrease in safety caused by their exclusion. It is imperative that the designer evaluate the needs of all users, as well as understand the priority of users within the route and each of their modal networks. Expanded FCS Matrix The preceding sections identified the specific issues related to each user group and the design considerations that need to be addressed when balancing each groupâs needs to deliver a con- textually appropriate multimodal design. Figure 25 shows the complete Expanded FCS matrix, which presents the treatment options for each user group (drivers, bicyclists, and pedestrians) and identifies the interactions along the context and roadway-type continuums. Proper contextual roadway designs require an understanding of how the roadway functions in its context and the needs of the potential roadway users. The Expanded FCS matrix can be used to identify preliminary requirements that should be given due consideration when assessing current and future roadway context and user needs. In a general project development approach, this process can assist with providing input and refining the purpose and need document, which establishes the framework for the design to be developed. Transit Rider Accommodation as an Overlay This section of the guidance presents the design considerations for accommodating transit within the Expanded FCS. Transit routes are typically fixed and well-defined by the local transit agency to meet the demands of the transit ridership. As such, there are no specific considerations to be provided as in the other modes. Close coordination and cooperation with local agencies is imperative in establishing the transit overlays in order to ensure proper accommodation of transit needs. The Guide for Geometric Design of Transit Facilities on Highways and Streets (AASHTO 2014) provides additional considerations for design elements of the transit overlays. Design Accommodations Transit routes may not require significant additional facilities beyond those provided for vehic- ular traffic, if mobility and speeds of the vehicular routes align with transit goals. However, curb- side lanes should be designed to accommodate the width of the design transit vehicleâtypically resulting in lane widths of 11â12 feet. Additional width may be necessary if bicycles share the curb lane with on-street low-separation facilities. Nodal treatment considerations should ensure wide
Modal Considerations and Accommodation 37 turning radii to accommodate transit vehicles. While low-order transit routes and infrequent turns may not require special accommodation, higher-priority routes for transit should have smooth turning radii to minimize unnecessary delays at turns. In addition, for high-priority or express routes, special controlled lanes should be considered for either bus rapid transit or light rail to designate lanes and/or areas for transit service within the right-of-way. Moreover, special operational parameters such as bus transit priority at signals may be contemplated, even though they may affect the travel time of other modes. Cooperation with local transit agencies will allow future transit facilities and routes to be identified in order to define future needs and land uses. On bicycle priority routes, which call for lower vehicle speeds, the wider lanes used to accom- modate transit may encourage higher speeds. When this occurs, increased separation of bicycle facilities may be an option to mitigate this increase in speed as well as to improve bicyclist safety. Nodal considerations include bus stop locations and potential bus pullouts. Pullout loca- tions should be placed and designed based on an examination of the safe operation and specific needs of the transit provider and its users. As previously noted with respect to pedestrian treat- ments, enhanced-width pedestrian facilities and connections to adjacent activity centers (such as shopping/business, transit stops, or even parking in park-and-ride areas) should be provided. In addition, some separation of the pedestrian facilities from the roadway may be considered in order to address possible safety concerns. Speed, mobility, accessibility, and separation level: H = high, M = medium, L = low Bicycle facility class: CC = citywide connector, NC = neighborhood connector, LC = local connector Pedestrian traffic levels: P1 = rare/occasional, P2 = low, P3 = medium, P4 = high Pedestrian facility width: * = site specific, Min = minimum, Wide = greater than minimum, Enhanced = wide for large congregating pedestrian groups Pedestrian facility separation should be considered in conjunction with driver target speeds. Figure 25. Expanded FCS multimodal matrix by context and roadway type.
38 An Expanded Functional Classification System for Highways and Streets Freight Accommodation as an Overlay Freight routes may not require significant additional facilities beyond those provided for vehicular traffic, if mobility and speeds of vehicular routes are consistent with freight movement. However, curbside lanes should be designed to accommodate the width of the design freight vehicleâtypically resulting in lane widths of 11â12 feet. Additional width may be necessary if bicycles share the curb lane with on-street low-separation facilities. Nodal treatments should ensure wide turning radii to accommodate trucks. While low-order freight routes and infre- quent turns may not require special accommodation, higher-priority routes for freight should have smooth turning radii to minimize unnecessary delays and possibility of crashes at turns. On bicycle priority routes, which call for lower speeds of vehicular traffic, the wider lanes used to accommodate freight may encourage higher speeds. When this occurs, increased separation of bicycle facilities may be imperative to avoid conflict and improve bicyclist safety. Note: See Case Study 2 for a demonstration of multimodal accommodation on an arterial.