Roadway Cross-Section Reallocation: A Guide (2023)

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7-1   Cross-Section Elements What Happens When You Change Your Cross Section? Changing a cross section can encourage people to use the street in new or different ways, fostering multimodal traffic and promoting the core objectives of the cross section. When the opportunity arises to reallocate public space, what are the cross-section elements to consider including in a street, and when should practitioners consider each cross-section element? How does each element help meet or stray from the goals for a corridor or community? This chapter describes core cross-section elements, as well as where they apply, and the key outcomes, con- siderations, and tradeoffs associated with each. Details of supporting research are provided in Appendix B. Cross-Section Makeup The cross section can be considered according to various zones or realms. (Agencies and other entities may not define zones or realms the same way.) C H A P T E R 7 The Multiple Minimums Problem Street elements are fundamentally defined by their widths. Each cross-section element requires a certain amount of space. Elements combine to determine the total cross-section width. In constrained environments, street designers may opt for the minimum dimensions for each element. However, when minimum dimen- sions for multiple elements are used, they can create safety concerns that would not otherwise exist. A minimally narrow travel lane next to a minimally narrow parking lane puts moving motor vehicles too close to parked cars, which could result in crashes. This condition, sometimes referred to as the “multiple minimums problem,” highlights the importance of considering context when developing street designs. Different zones serve different users and include different cross-section elements. Table 7-1 lists the different cross-section zones alongside their identifying traits as used herein. The realms describe the primary function of each portion of the cross section, detailing what activities and purposes are expected. Figure 7-1 provides an example of cross-section realms as used by the Oregon DOT.

7-2 Roadway Cross-Section Reallocation: A Guide General-Purpose Lanes Description: General-purpose lanes facilitate travel for various modes, especially those that do not have other dedicated space on the street. Drivers of personal vehicles, freight trucks, delivery vehicles, bicyclists, micromobility device users, and people riding and driving buses may all use these lanes. Where pedestrian facilities do not exist, pedestrians may also use this space. If there are dedicated bicycle lanes or bus lanes, bicyclists and buses are more likely to travel in those spaces instead of in general-purpose lanes. In addition to through travel lanes, general- purpose lanes may be dedicated right- or left-turn lanes or two-way left-turn lanes. Streets with general-purpose lanes may be two-way or one-way (Figure 7-2). Applicability: General-purpose lanes are applicable to most streets, including all streets where drivers should be accommodated. However, in cases where parallel routes for motorized traffic are provided and/or walking and biking demand is high, general-purpose lanes may not be necessary. Two-way left-turn lanes, a type of general-purpose lane, can be considered when assessing general-purpose lane needs. For example, two-way left-turn lanes may be appropriate on roads with many access points, especially in areas with a history of rear-end crashes or left-turn-related crashes. Consider using access management techniques to further reduce the number of conflict points along a street. Key Outcomes: General-purpose lanes provide access and mobility, especially for drivers. Pro- viding additional lanes for driving can lead to crashes, intensify emissions and other environmental degradation, create car-centric public spaces, and induce demand for more driving. Where traffic demand exceeds capacity and non-automobile alternatives are insufficient, congested streets can also lead to increased emissions and possible traffic diversions (Figure 7-3). Figure 7-1. Example of cross-section realms from Oregon DOT Blueprint for Urban Design. Zone Location Cross-section Elements Frontage Immediately adjacent to the right-of- way edge Sidewalks Pedestrian Parallel to the street between land use and the curb Sidewalks Shared-use paths Transition Immediately adjacent to the curb or sidewalk edge Curbside space Bicycle lanes Travel Center of the right-of-way General-purpose lanes Bicycle lanes Bus lanes Medians Table 7-1. Cross-Section Zones.

Cross-Section Elements 7-3   Figure 7-2. Two-lane street with turn lanes in Portland, OR. Note: See Appendix B for more detail Figure 7-3. Outcomes of adding general-purpose lanes.

7-4 Roadway Cross-Section Reallocation: A Guide Key Considerations and Tradeoffs: In most situations, it is appropriate to provide a general- purpose lane. In extremely low-speed and low-vehicle-volume environments (up to about 10 mph; about 100 vehicles per hour at the peak), this may be enough: all modes can share this space. These “shared streets” or “living streets” are generally pedestrian-rich environments. They typically have few crashes, and the crashes that do occur are usually low impact. Such streets are economi- cally vibrant, encourage social connection, and may encourage a mode shift from driving, thereby reducing environmental impacts. As speeds and motor vehicle volumes increase, separating modes and providing more fre- quent crossing opportunities become imperative. Practitioners should prioritize separation by starting with users of the lowest-volume and lowest-speed modes and then working up: first pedestrians, then bicyclists, then motor vehicles, including freight and transit; each mode’s users should be provided with bidirectional travel as that mode is separated. In the past, operational motor vehicle analysis was a key factor in determining how many general- purpose lanes should be provided. Current research shows providing multiple lanes in each direction can induce further demand, leading to many adverse effects (as noted in the preceding Key Outcomes discussion) (Lee, Klein, and Camus 1999; Hymel, Small, and Van Dender 2010). Where travel demand is increasing, it is necessary to invest meaningfully in the non-automobile network to support more travel choices. Simply making driving more difficult is not sufficient to shift people to other modes if the alternatives are even less desirable. Most general-purpose streets are bidirectional; however, in some environments, one-way streets can be appropriate. In a downtown setting with low speeds, frequent high-visibility crossing opportunities, a consistent block structure, and parallel routes providing access in alternating direc- tions, a one-way street can provide access for many users effectively. Multilane one-way streets without regular high-visibility crossings or a consistent parallel route can create challenges for accessing land uses along the road. On streets where there is no space to provide necessary multimodal facilities (e.g., sidewalks, bike lanes, and bus lanes), making the street one-way can free space to provide appropriate facilities for all users. For example, contraflow lanes for other modes (bus lanes, bike lanes) can increase network connectivity, especially if there are no nearby parallel routes for those modes. In applying contraflow bike lanes, the bikeway design must focus on providing a sufficient buffer between the contraflow bike lane and general-purpose lanes and on creating visibility and aware- ness of contraflow bicyclists to establish an expectation that drivers should look for contraflow bicyclists, particularly at intersections. Table 7-2 presents recommended general-purpose lane widths by vehicle type and lane type. 1 Freight corridor or frequent bus use Table 7-2. Recommended general-purpose lane widths.

Cross-Section Elements 7-5   Bus Lanes Description: Bus lanes provide dedicated space for transit vehicles (Figure 7-4). These lanes may be implemented along an entire street segment or just in key stretches, such as at major intersections. The purpose of bus lanes is to improve the efficiency and reliability of buses which may otherwise be slowed by congestion. Bus lanes are regulated by “Bus Only” signs and pavement markings and may be augmented with red pavement (FHWA 2009). It is recommended that bus lanes be at least 11 feet wide, although, in some urban settings, 10-ft-wide lanes may be appropriate. Transit signal priority is desirable to reduce transit delays, and high-frequency bus lanes may be paved in concrete or other durable materials to withstand the effects of bus use. Business access and transit (BAT) lanes and peak-hour bus lanes (i.e., curbside parking lanes that convert to bus lanes during peak hours) may be applicable in places that do not have high enough frequencies to support an exclusive space, or where business access is a higher priority. Applicability: Bus lanes are most applicable in areas with high-frequency transit that is likely to be slowed by congestion or where long-range transit plans identify the location as a high- frequency bus route or corridor. Additionally, bus lanes may be applicable on corridors with both high demand for transit and lower bus frequencies. Bus lanes should always be considered where frequencies approach 3 to 4 minutes (∼20 buses per hour). On streets with bus frequencies between 5 and 6 minutes (∼10 buses per hour), bus lanes would improve transit service, but motorists are more likely to use the lane for loading, unloading, and parking. On streets with less frequent transit service, practitioners may consider bus lanes depending on context. Other performance measures that can be used for selecting streets where dedicated lanes may work best include person throughput and average transit speed and reliability. Key Outcomes: Providing a bus lane can make transit more attractive by improving bus reli- ability and reducing transit travel times, providing increased access to businesses and commer- cial areas, and reducing transit operating costs. Transit provides mobility for people who are very young, those who are elderly, those with disabilities, those without access to a vehicle, and others without access or the ability to take other modes (Figure 7-5). Figure 7-4. Bus lane in San Francisco, CA.

7-6 Roadway Cross-Section Reallocation: A Guide Key Considerations and Tradeoffs: Bus lanes may be shared with other modes in some cases. Shared bus and bike lanes are sometimes used in areas where physical constraints and local pri- orities do not allow for each mode to have dedicated space and where bus speeds are low. In urban areas, buses and bicyclists often have similar overall travel times, which may make shared bus and bike lanes seem feasible. In practice, however, buses have greater mass, travel faster than bikes between stops, and have frequent stops, while bicyclists travel at much more consistent speeds. These travel patterns can create “leapfrogging” between buses and bicyclists that can cause conflicts and delay for each mode. Situations where a shared lane might be considered include business districts with slow speeds (20 mph or less) and where bus lanes would be used by a low volume of buses and a low-to- moderate volume of bicyclists (which can improve perceptions that the lane is being used). Bus lanes can also be shared with other motor vehicles. At intersections or along stretches with driveways or access points, shared bus and turn lanes or BAT lanes can dedicate space for turning while providing through-bus facilities. In shared bus and turn lanes, buses may be delayed behind right-turning vehicles at signalized intersections, which has been shown to reduce the travel time benefits to buses nearly in half (Kittelson & Associates, Inc. et al. 2013). An offset bus lane allows drivers to move into a right-turn lane without blocking bus traffic. At intersections, signal phasing should support these movements to allow buses to progress without waiting in traffic queues. The recommended width for bus lanes is 11 feet in all contexts. Bicycle Lanes Description: Bicycle lanes provide dedicated space for bicyclists and, where permitted by local regulations, people using micromobility devices. Bicycle lanes may be indicated by mark- ings and may include a buffer and/or physical vertical separation (Figure 7-6). The degree and Note: See Appendix B for more detail Figure 7-5. Outcomes of reallocating space to bus lanes.

Cross-Section Elements 7-7   type of separation between bicycle lanes and general-purpose lanes should be based on the speeds and volumes of adjacent motor vehicles, as discussed in Chapter 6. Higher traffic speeds and volumes call for wider and more robust separation between lane types. Bike lanes are typically unidirectional and are on the outside of the travel lanes; in some cases, they can be bidirectional and located elsewhere on a street, such as in the center median space or on the left side of a one-way street. Bicycle lanes may be painted green, especially in areas of potential conflict with other modes. Applicability: Bicycle lanes are applicable and necessary to provide mobility and access for bicyclists on most urban and suburban streets. Streets with very low volumes and speeds typically do not need separate space for bicyclists. Advisory bike lanes may be an option on streets with less than 3,000 vehicles per day, most often in low-density contexts. Streets with volumes greater than ∼4,000 vehicles per day and speeds exceeding 20 mph require bike lanes. Separated bike lanes, featuring vertical and horizontal separation from traffic, provide safe and comfortable bike facilities on streets with higher-volume or higher-speed vehicle traffic. In situations with limited space, parallel high-comfort bike facilities can provide a network connection for bicyclists. Shared-use paths that run parallel to a street can meet the needs of bicyclists and pedestrians in some contexts, usually where the number of people walking and biking is low. Key Outcomes: Providing a safe bicycle facility is necessary. A low-stress biking network can make it attractive to bike, thereby improving community health, sustainability, and access, as well as providing increased incentives for local spending, thus improving the economic vitality of a local area (Figure 7-7). Key Considerations and Tradeoffs: Consider the purpose and context of the street and bicy- cle facilities when deciding whether to provide bidirectional (e.g., a two-way bike lane) or uni- directional bicycle facilities. One-way bike lanes on the outside of general-purpose travel lanes provide access to the destinations along that side of the street. Providing both frequent opportu- nities to cross and bicycle parking can enable access to destinations across the street. A two-way facility on one side of the street can be appropriate if it helps cyclists make a connection (e.g., to shared-use paths or trails) that would eliminate gaps in biking networks, if there are few to no destinations along the road, or if there is a significantly greater number of driveways or conflict points on one side of the road and the two-way facility is provided on the other. A raised bike lane is located outside the curb-to-curb width and can be elevated either at sidewalk level or between the street and sidewalk (e.g., 3 inches above the street level). Raised bike lanes provide increased safety and comfort due to their location and separation from traffic. Figure 7-6. Bicycle lanes in Portland, OR.

7-8 Roadway Cross-Section Reallocation: A Guide Table 7-3 presents recommended bike lane and separation widths for urban and suburban streets based on traffic context. Sidewalks Description: Sidewalks are dedicated spaces for pedestrians as well as individuals using mobility devices. Sidewalks are separated vertically from the roadway, and separation may incorporate horizontal buffers (Figure 7-8). The higher the speed and volume of traffic on the adjacent roadway, the wider the buffer should be between motor vehicles and pedestrians on the sidewalk. Applicability: Sidewalks on urban and suburban roadways provide mobility and access for people walking. On shared streets, sidewalks may be at the same grade as the roadway, and people walking may use the street for access. Key Outcomes: Providing a minimally safe sidewalk is necessary. A comfortable sidewalk can (1) make it attractive to walk, thereby improving community health, sustainability, and access and (2) increase people’s incentive to spend locally, thereby improving the community’s eco- nomic vitality (Figure 7-9). Key Considerations and Tradeoffs: Horizontal buffer space between the sidewalk and curb can be used for many purposes that also support corridor goals. For example, providing street trees or green infrastructure for stormwater management can improve aesthetics, provide shade, and create improved environmental outcomes; benches and street furniture can improve social outcomes; bike and micromobility device parking can improve mode shift outcomes; and curb- side dining can improve economic outcomes. Wider sidewalks should be provided in areas with a greater propensity or goals for pedestrian activity. Especially in downtowns and commercial centers, the sidewalk should be wide enough for multiple people to comfortably walk side-by-side and to pass other groups. Note: See Appendix B for more detail Figure 7-7. Outcomes of adding bicycle lanes.

Cross-Section Elements 7-9   Table 7-3. Recommended Bike Lane and Buffer Widths. *Light separation includes flexible delineators, some rigid bollards, plastic planter boxes, rubber curbs, or precast concrete curbs/parking stops. <2,000 No centerline Mixed traffic (15-19 feet) Not applicable (Not applicable) Curbside (Not applicable) MassDOT*, CROW2,000-4,000 >4,000 Bike lane (5.5 feet) Paint (Not applicable) FHWA, MassDOT, CROW *FHWA = Schultheiss et al. 2019; NACTO = NACTO 2014; MassDOT = MassDOT 2015; CROW = Koster 2016 <1,500 No centerline Mixed traffic (15-19 feet) Not applicable (Not applicable) Curbside (Not applicable) NACTO, MassDOT 1,500-3,000 1 lane per direction Bike lane (5.5 feet) Paint (Not applicable) Curbside (1 foot) NACTO, MassDOT, CROW 3,000-6,000 Buffered bike lane (5.5 feet) Paint (1 foot) Curbside (1 foot) FHWA, NACTO, MassDOT, CROW >6,000 2 lanes per direction Separated bike lane (6 feet) Light separation* (1 foot) Floating (2 feet) NACTO, MassDOT, CROW Raised bike lane (6 feet) Light separation (2 feet) Two-way bike lane (10 feet) Light separation (2 feet) Floating (1 foot) <6,000 Any Separated bike lane or raised bike lane (6 feet) Two-way bike lane (10 feet) Light separation (1 foot) Floating (2 feet) NACTO, MassDOT, CROW >6,000 Light separation (2 feet) Vehicle Volume (ADT) On-Street Parking Location (Additional Buffer Width) Supported By Street Buffer Type (Width) Facility Type (Width) # of Travel Lanes Vehicle Volume (ADT) On-Street Parking Location (Additional Buffer Width) Supported By Street Buffer Type (Width) Facility Type (Width) # of Travel Lanes Vehicle Volume (ADT) On-Street Parking Location (Additional Buffer Width) Supported By Street Buffer Type (Width) Facility Type (Width) # of Travel Lanes (continued on next page)

7-10 Roadway Cross-Section Reallocation: A Guide *Heavy separation includes vehicle parking, concrete planter boxes, reinforced rigid bollards, cast-in-place concrete curbs, concrete barriers, or guide rails. Should have half-meter clearance between bike and object. Any Any Separated bike lane or raised bike lane (6 feet) Two-way bike lane (10 feet) Heavy separation* (5 feet) Floating (2 feet) FHWA, NACTO, MassDOT, CROW Any Any Raised bike lane (6 feet) Raised two- way bike lane (10 feet) Multiuse path (12 feet) Heavy separation (6 feet) Not applicable (Not applicable) FHWA, NACTO, MassDOT, CROW On-Street Parking Location (Additional Buffer Width) Supported By Vehicle Volume (ADT) Street Buffer Type (Width) Facility Type (Width) # of Travel Lanes On-Street Parking Location (Additional Buffer Width) Supported By Vehicle Volume (ADT) Street Buffer Type (Width) Facility Type (Width) # of Travel Lanes Table 7-3. (Continued). Figure 7-8. Sidewalk along a street in Washington, DC. Table 7-4 presents recommended sidewalk and buffer widths based on land use and traffic context. This guidance recommends 6-foot sidewalks even in low-volume contexts to provide comfortable passing space for two people in wheelchairs. Street crossings are as important to pedestrian safety as sidewalks. Although they are not tech- nically a component of a cross section, street crossings are fundamentally connected to cross- section design. The distance between crossing opportunities influences access opportunities and

Cross-Section Elements 7-11   Note: See Appendix B for more detail Figure 7-9. Outcomes of adding sidewalks. determines how likely a pedestrian is to cross the street outside of a crosswalk. Table 7-5 presents the maximum crosswalk spacing based on land use and street context. Table 7-6 provides guidance on the type of crossing treatment needed based on traffic context. As vehicle volumes and speeds get higher it becomes increasingly critical to provide signalized crossing opportunities. Sidepaths/Shared-Use Paths Description: Sidepaths are shared-use paths that exist within a roadway corridor (Figure 7-10). They provide dedicated space for bidirectional travel for people walking, biking, using mobility devices, or using scooters or other micromobility devices. Table 7-4. Recommended sidewalk and buffer widths.

7-12 Roadway Cross-Section Reallocation: A Guide 1,000 ft (3-4 blocks) Table 7-5. Recommended Maximum Crosswalk Spacing. Table 7-6. Recommended Crossing Treatments. 

Cross-Section Elements 7-13   Applicability: Sidepaths are mainly applicable in areas with few motor vehicle driveways or access points and lower volumes of people walking and biking. Sidepaths can be used along higher-speed and/or higher-volume streets to provide a completely separated space outside of the street for pedestrians and bicyclists. In most cases where it is applicable to provide a sidepath, the path can eliminate the need for bicycle lanes and sidewalks. Key Outcomes: When provided in an appropriate location, a sidepath can be a comfortable, ded- icated space attractive to people walking or biking. Sidepaths can improve community health, sustainability, and access and incentivize local spending, thus improving the community’s economic vitality (Figure 7-11). Key Considerations and Tradeoffs: In many situations, especially urban areas or denser or destination-focused suburban areas, providing dedicated walking and biking facilities that are Figure 7-10. Sidepath in Harrisburg, PA. Note: See Appendix B for more detail Figure 7-11. Outcomes of adding sidepaths/shared-use paths.

7-14 Roadway Cross-Section Reallocation: A Guide Table 7-7. Recommended sidepath and buffer widths. separate from each other is preferable to combining these modes on a sidepath. Table 7-7 pres- ents applicability and design considerations based on anticipated volume. Especially in areas with moderate to high volumes, combining these modes can cause con- flicts, inhibit efficient travel, and be uncomfortable, thus reducing or negating the anticipated outcomes outlined previously. In areas with low user volumes, few intersections and few access points, and a constrained right-of-way, however, a well-designed sidepath can be an efficient use of space and provide pedestrians and bicyclists with a facility separated from the roadway. One key concern with providing sidepaths instead of directional bicycle facilities is the lack of driver awareness about contraflow bicycle traffic (higher-speed traffic than pedestrians, who are expected to travel bidirectionally) at intersections and access points. If a motor vehicle is turning left, the driver is more likely to be aware of or look for traffic traveling toward them. Skip striping and signs that indicate two-way bicycle travel through crossings at intersections are key to creat- ing awareness of the bidirectional traffic. At signalized intersections, treatments that give people walking and biking a head start can help increase their visibility. Another key consideration when providing sidepaths is the connection to other biking facili- ties. If a sidepath connects to a unidirectional bike lane at an intersection, the design of the inter- section should consider the efficiency and safety of connecting bicyclists to the infrastructure they will need to use to continue their path. Diagonal crossings can reduce the need for two-stage crossings, which can slow bicyclists and increase crossing exposure. Clear and continuous pavement markings and signs can also be effective in instructing bicy- clists as to how to make connections, which can otherwise be uncomfortable or unclear. A lack of clarity about connections may encourage crossing in ways or locations that increase exposure or the number of potential conflict points. Striping on the ground to encourage separation between people walking and biking in differ- ent directions, especially at intersections or areas with higher volumes, can make travel paths clear and decrease conflicts between these modes. Medians Description: Medians may be provided to separate two opposing directions of traffic on a street (Figure 7-12). Medians reduce permitted left turns and can improve safety along a corridor.

Cross-Section Elements 7-15   Medians may be painted to provide visual separation or raised to provide a physical barrier. Raised medians can improve safety for pedestrian crossings by providing a refuge. Applicability: Medians are typically applicable where you have few access points, would like to restrict access, or have a history of crashes involving vehicles crossing the centerline, including head-on and le-turning crashes. Key Outcomes: Installation of medians helps to create pedestrian crossing refuges, con- trols turning movements, and reduces conflicting vehicle paths, thereby improving safety. Medians can also contribute to increased green space leading to improved equity and envi- ronmental outcomes (Figure 7-13). Key Considerations and Tradeos: Medians may be narrow or wide and made of dier- ent materials, and the size, shape, and dimensions of a median can change the benets. Wider medians can include trees or plants, which can provide shade, improve the environment, and enhance placemaking. Figure 7-12. Median on a street in Baltimore, MD. Figure 7-13. Outcomes of adding medians.

7-16 Roadway Cross-Section Reallocation: A Guide Providing a 6-ft or wider median allows for a pedestrian refuge island for those crossing and can increase safety and comfort for pedestrians. Two-way left-turn lanes or channelized turn lanes can be provided in key areas to allow access between medians. Because medians restrict turns and corridor access, they remove friction along a corridor. Although this can have many positive safety benefits, it may also encourage drivers to move at higher speeds (Butorac et al. 2018). Curbside Space Description: Every street has a curbside, but whether the space next to the curb is dedicated to travel or curb access depends on the street’s purpose, surrounding land use, and the community’s goals. Use of curbside space can take many forms, including on-street parking; space for streateries or food trucks; parklets; bike share/micromobility stations; pickup and dropoff or loading and unload- ing space for transit, freight, and other vehicles; curb extensions/bulb-outs; and green infrastructure stormwater treatment (see Figures 7-14 through 7-22). These uses may vary along a corridor. Figure 7-14. Curbside parking in San Diego, CA. Note: See Appendix B for more detail Figure 7-15. Outcomes of adding curb extensions.

Cross-Section Elements 7-17   Figure 7-16. A flex post curb extension in Washington, DC. Figure 7-17. Outcomes of adding multimodal parking and pickup/drop-off. Note: See Appendix B for more detail Figure 7-18. A bike corral along a curb in Washington, DC.

7-18 Roadway Cross-Section Reallocation: A Guide Note: See Appendix B for more detail Parking Figure 7-19. Outcomes of adding streateries/food trucks. Figure 7-20. A street café along curb space in Baltimore, MD.

Cross-Section Elements 7-19   Figure 7-22. A parklet along the curb in Baltimore, MD. Figure 7-21. Outcomes of adding Parklets. Note: See Appendix B for more detail

7-20 Roadway Cross-Section Reallocation: A Guide Applicability: Curbside space should be provided on access streets, which are typically character- ized by lower volumes and speeds and located in residential and commercial areas. Distributor streets may not need to provide space for curbside purposes. Key Outcomes: On-street parking improves access for people driving and reduces the time spent by drivers searching for parking. On-street parking at destinations increases driving by creating incentives for people to drive compared with other travel modes. Appropriately priced street parking can improve space turnover, supporting adjacent retail businesses by increasing the likelihood of available parking spaces near destinations. Key Considerations and Tradeoffs: Different types of curb uses are appropriate on different types of roads. In low- and medium-density residential areas, parking is often an appropriate use for curb space, because parking provides access and can create friction that slows speeds. Including curb extensions and green stormwater infrastructure (e.g., rain gardens) throughout can improve safety and environmental outcomes. In higher-density and commercial areas, parklets and streateries can improve economic and social vitality. Focused freight loading/unloading zones are often appropriate to supply goods to businesses. Providing transit and mobility as a service (Uber, Lyft, etc.) pickup and dropoff areas, or dedicated space for bicycle, micromobility, and personal-vehicle parking increases multimodal access to these areas. Bicycle and micromobility parking, transit stations, and pickup/dropoff zones can be more efficient than typical personal-vehicle street parking because they can serve more people per day. Where car parking is provided, paid parking strategies can encourage parking turnover and generate revenue. Curb extensions and green stormwater infra- structure are also relevant in these contexts. Often, a mix of uses is especially appropriate within higher-density or commercial contexts. Curbside activity (e.g., parking, loading) will interact with adjacent cross-section elements such as bike lanes and sidewalks. These interactions need to be considered to ensure appropriate buffer space is provided. Parking lanes are recommended to be 7 to 9 feet wide. Summary What cross section elements are included and how they are designed dictates who can use a street and how it can be used. The presence or absence of elements supporting each of the dif- ferent modes affects outcomes in various ways. The dimensional requirements for each element vary depending on surrounding land uses and traffic speed and volume.