Roadway Cross-Section Reallocation: A Guide (2023)

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4-1   Planning Context Set Your Goals A street cross section is such a basic element of our transportation system that it can be easy to overlook the power it has to convey priority, affect safety, and encourage or discourage behav- iors. Some effects are straightforward: a bike lane communicates that bicyclists are expected on a roadway. Other effects are more subtle, like the relationship between wider streets and vehicle speed—People tend to feel comfortable driving at high speeds when streets are wide, even when the road is signed at a lower speed limit. Overall, roadway design and allocation are powerful tools that directly and indirectly affect a community’s safety, equity, health, environment, and economy in multifaceted ways (Figure 4-1). Because of the power of design, cross sections must be intentionally aligned with the community goals and needs reflected in plans and policies. Street designs should align with the land-use contexts of the communities they pass through. The following sections detail how roadway space allocation and design choices can affect spe- cific community needs and goals related directly to transportation (i.e., safety and mode shift) and indirectly to transportation (i.e., environment, health, economy, and equity). Transportation Policies and Goals Policies and goals directly related to transportation can be categorized as relating to safety or to mode shift. These categories are discussed in more detail in the sections below. Safety The experience of safety changes for all roadway users when a cross section is altered, even if that change is not measured in crashes in the near term. Increased roadway width or lanes dedicated to moving vehicles can indirectly encourage motorists to increase speed, even when C H A P T E R 4 Figure 4-1. Relationship between Roadway Design and Community Impacts.

4-2 Roadway Cross-Section Reallocation: A Guide the posted limit remains the same. For pedestrians, narrow sidewalks next to multiple lanes of traffic—particularly high-speed traffic—are uncomfortable and create a consistent crash threat. Even when there is ample sidewalk width, pedestrians are at risk if there are insufficient and inconvenient pedestrian crossings. For bicyclists, both riding in the street and crossing the street can feel and be risky, particularly when bicyclists are riding in unprotected facilities sandwiched between motorists traveling over 25 mph and parked motorists opening car doors. In contrast, for motorists, removing travel lanes can lead to lower motorist volumes, but rarely does it increase the risk for motorists. A narrower right-of-way also encourages motorists to slow down, which improves safety for all street users. The effect is strengthened when accompanied by other speed management techniques. Repurposing vehicle lane space for bicyclists generally leads to increased perceived safety. Although increases in the number of bicyclists may lead to an increase in the overall number of crashes, the number of crashes per bicyclist (crash risk) decreases (Kehoe et al. 2022). For pedestrians, increased sidewalk width and buffer space tend to increase comfort and per- ceived safety. Reduced crossing width—particularly if there are fewer lanes to cross, not just narrower lanes—reduces pedestrian exposure to vehicles and decreases the crossing burden. Greater perceived and objective safety, as measured by a reduction in crashes or near misses, can encourage walking and bicycling. This, in turn, increases opportunities for physical activity, neighborhood life, and economic activity and decreases car use and unhealthy emissions. Any changes to the street design are likely to have a magnified effect at night, given well- established patterns of human attention and limitations to peripheral vision that result in reduced perception-reaction time (Dewar and Olson 2015). Carefully considering dark conditions in roadway redesign is critical to reversing the rising trend of pedestrian fatalities that began in 2010 (Retting 2017). Lighting at intersections and along streets can help mitigate the increased risk in darkness, but lighting alone is unlikely to avert higher-speed crashes (Sanders, Schneider, and Proulx 2022). Speed management—through both speed limits and roadway design—is critical to addressing the reduced human capacity to perceive and react in time to avoid a collision. Because the USDOT’s 2022 National Roadway Strategy states that safety is the USDOT’s top priority, this Guide explicitly prioritizes safety for roadway users, beginning with the least pro- tected, and urges all practitioners to work toward these goals. What About Personal Safety? In addition to traffic safety, personal safety concerns (e.g., concerns about being robbed, assaulted, or profiled while walking and biking) can also be a barrier to comfortable multimodal travel. Research has shown that personal safety concerns affect minority communities (Brown 2016). Although this Guide focuses on cross-section changes that address traffic safety, transportation professionals should also investigate and address the personal safety concerns within their communities. Mode Shift Many cities and regions seek to reduce congestion, air pollution, and traffic risk by shifting travel away from automobiles to more sustainable modes such as transit, bicycling, and walking.

Planning Context 4-3   Mode shift goals also support safety goals in several ways. For example, increasing the number of people walking and bicycling tends to lead to safer conditions for pedestrians and bicyclists— a concept known as “safety in numbers” (Kehoe et al. 2022). This may be a result of motorists’ increased awareness of and safer behavior around these modes. Also, if more motorists experi- ence traveling by other modes, it increases their awareness of others traveling by that mode when they are driving (Basford et al. 2002, Connerly et al. 2006). Last, reducing the number of cars on the road reduces the exposure non-motorists have to car traffic and car users have to each other. Roadway design and allocation, by encouraging or discouraging certain types of travel, are critical in supporting mode shift. For example, research has shown that bicycle volumes increase when bicycle facilities are built, particularly when such facilities connect to a bicycle network (Dill 2003, Marqués et al. 2015). Similarly, when lanes are added for motor vehicles, vehicle volumes tend to increase. Similar dynamics apply to pedestrians when sidewalks and cross- ings are ample and connected, communicating that pedestrians are expected. If mode shift is a goal, allocating sufficient space for higher-priority modes in the right-of-way is critical. Once mode shift goals are achieved, practitioners can work to maintain their community’s desired mode split. A modal hierarchy reflects how users of a given transportation system are prioritized. Ideally, this hierarchy is detailed in local policy goals and prioritizes walking, bicycling, and transit, given that “people who take public transportation, walk, bike, roll, or use a motorcycle require special attention since they lack the protections gained from being inside a motor vehicle” (USDOT 2022). In the absence of a stated modal hierarchy, agencies are urged to develop one to guide roadway design decisions. An example from Portland, Oregon, is shown in Figure 4-2. Prioritizing by roadway user mode naturally influences other areas of prioritization. Choosing to prioritize safety will result in a substantially different street design than when motorist speed and convenience are the priority. Planning for motorist comfort and convenience has resulted in multilane streets dominated by vehicles and unsafe relative to other parts of a transportation system (Schneider et al. 2021). In contrast, prioritizing pedestrians and bicyclists tends to create a roadway safer for everyone (Marshall and Garrick 2011). Figure 4-2. Modal Hierarchy for Portland, Oregon.

4-4 Roadway Cross-Section Reallocation: A Guide Establishing a modal hierarchy also allows practitioners to prioritize different modes along different streets within the broader transportation network. Although all streets should enable safe travel for all users, different streets can have different modal priorities. Based on their roles in the transportation network, some streets may primarily serve freight, transit, or nonmotor- ized users. Indirect Transportation Policies and Goals Policies and goals indirectly related to transportation can be categorized as relating to the environment, health, the economy, and equity. These categories are discussed in more detail in the sections below. Environment In addition to climate change, local air quality is particularly affected in cities and regions where topography and geography create an air basin that traps polluted air or smog. As a result, many cities and regions have adopted policies and stated goals aiming to reduce transportation- related environmental pollution. Roadway design plays a pivotal role in helping communities meet their environmental goals by allowing and encouraging mode shift and incentivizing cars and trucks that operate with maxi- mum fuel efficiency and minimal net emissions. In some European cities (e.g., Paris, Malmö, Copenhagen), practitioners reallocate street space to other modes [e.g., bicycles or bus rapid transit (BRT)] in part to keep street-level vehicle emissions closer to the center of the street and away from sidewalks, residences, and businesses (Gehl 2021). Shifting travel from single-occupancy vehicles to buses, carpools, bicycles, or feet in the short term reduces energy consumption and the amount of space needed to support traveling and parked vehicles. A long-term, community mode shift can save resources related to maintenance and construction. In some cases, paved surfaces can be removed and the associated damage caused by urban heat islands and toxic stormwater runoff reduced. As noted previously, streets that communicate that pedestrians, bicyclists, transit users, and other non-automobile modes are expected and prioritized help encourage the mode shift critical for environmental well-being. Health Roadway design decisions directly affect public health in ways in addition to safety. These effects can be negative or positive. For example, streets that encourage car and truck traffic increase air and noise pollution, negatively affecting nearby residents. Systemic racism and classism and his- torical decisions about where major roadways were built have disproportionately concentrated harms in neighborhoods with fewer resources to deal with negative health effects, creating a vicious cycle of compounding public health and equity crises (Rodgers 2022). Encouraging automobile traffic also correlates with high concentrations of paved land in the form of roadways or parking lots provided to store cars. In turn, extensive pavement compounds the urban heat island effect, which raises local temperatures, contributes to dangerous heat waves, and can further trap localized air pollution. Paved areas also tend to increase stormwater runoff, which can lead to groundwater contamination. These negative unintended consequences are closely related to roadway design effects on equity and the environment. Roadway design decisions can also support health. Encouraging active transportation, such as walking and bicycling, and allocating space to support physical activity all improve a com- munity’s health. A well-designed protected bicycle facility or multiuse path tells people they

Planning Context 4-5   are welcome and expected to bike, roll, and use scooters. Buffered sidewalks, particularly when accompanied by street trees for shade, communicate value to people walking and provide a comfortable space. When provided frequently, high-quality pedestrian crossings not only reduce people’s exposure to traffic risk but help them cross at convenient times and ease burdens asso- ciated with walking, which may include carrying loads, accompanying small children, walking with a disability, or walking in inclement weather. In short, roadway design communicates who is valued and how they should be treated. Economy Roadway design also affects the local economic environment. Several studies have found that installing a bicycle lane leads to more bicycle-based shopping traffic and higher sales overall (Schaller Consulting 2006, Sztabinski 2009). In general, where people feel safer and more com- fortable, they are more likely to want to spend time (Sanders and Cooper 2013). This research highlights that travel lanes and on-street parking may be reallocated to other uses to yield greater economic outcomes. In contrast, streets that solely or mainly cater to automobile traffic, particularly higher-speed traffic, may attract drivers, but discourage people who walk or bicycle and may therefore lead to lower economic activity overall. Commercial rent patterns illustrate this correlation at a macro scale, given that more walkable and bikeable areas routinely demand higher rents than automobile-oriented areas (Leinberger and Rodriguez 2016). These types of outcomes must be considered when choosing between street-design elements that encourage or discourage various users. Freight access is another economic aspect that should be considered in roadway design. Freight-Sensitive Design The City of Portland, OR, painted bike boxes and prohibited right turns on red lights at several locations after two bicyclists were killed in quick succession by commercial trucks turning right across their paths in 2007 (Mionske n.d.). The bike boxes increase bicyclist visibility, and the prohibition against turning right on red ensures cyclists can enter the bike box without conflicting with drivers who might be turning. Although it is ideal to separate freight from routes with even moderate pedestrian or bicyclist volumes, this separation is not always possible. It may be particularly difficult in dense downtowns with lots of economic activity that have a high demand for both freight use and safe conditions for people who are walking, rolling, bicycling, and using scooters. Where freight routes must overlap with streets with moderate or higher amounts of pedestrian, bicyclist, and/or micromobility traffic, freight access must be secondary to the safety of those users. In practice, this means increasing the visibility of people walking, biking, or rolling; con- trolling vehicle speed and turning movements; and directing and monitoring parking to ensure that freight has the space needed to load and unload without blocking bike lanes—a common complaint in dense urban areas.

4-6 Roadway Cross-Section Reallocation: A Guide Equity Equity is related to all the categories described previously (Rodgers 2022). The streets with the highest number of crashes in the United States are disproportionately in neighborhoods that are home to communities of color and/or lower-income households (Schneider et al. 2021, Mansfield et al. 2018). These streets tend to carry high volumes of fast-moving traffic, resulting in increased localized air pollution for nearby residents who are already at increased risk of chronic illness. Wide streets with high motor vehicle speeds also discourage people from walking and bicy- cling because they are unsafe (NACTO 2020, FHWA 2009). This effect is reinforced by a lack of bicycle and pedestrian facilities. In neighborhoods with low car ownership, this combination of feeling or being unsafe and lacking other travel options can lead to isolation from community resources and job opportunities. Although roadway design alone cannot fully address the past harms to these neighborhoods, it can and should play a critical role in creating a healthy future for communities harmed by cur- rent and past transportation decisions and investment patterns. Sustained and intentional com- munity engagement is key to ensuring that roadway design meets community needs. Equitable community engagement includes plentiful opportunities to collect meaningful public input, particularly from those who have traditionally been left out and/or disengaged from decision- making processes. Transportation agencies can most effectively engage with diverse communities if they have a diverse transportation staff. In cases where diverse transportation staff are unavailable for a specific effort, agencies can contract with community organizations to support engagement. When agencies work with community organizations, those organizations should have a mean- ingful role, including the power to affect decisions and outcomes (Greenlining Institute 2019, Mehta 2012). Roadway design and allocation is a powerful tool that affects people’s ability to live healthy lives, access needed services and opportunities, feel comfortable and welcome in a space, and be safe in a space. The effects on community safety, mode use, the environment, public health, the economy, and equity are intertwined in complex ways. The result is that, when we allocate space based on an automobile-centric paradigm, we negatively affect street users and nearby residents in multiple ways, as shown in Figure 4-3. In contrast, a roadway design that prioritizes the safety of all road- way users can have myriad benefits, as shown in Figure 4-4. The remainder of this Guide is designed to help practitioners evaluate combinations of street- design elements so as to select a roadway reallocation strategy that prioritizes safety, particularly for the most vulnerable users, while meeting other community goals. Summary Street design and roadway allocation are powerful tools that directly and indirectly affect community safety, mode use, the environment, public health, the economy, and equity in multi- faceted ways. Because of the power of design, cross sections must be intentionally aligned with community goals and needs reflected in plans and policies. Sustained equitable engagement is key to repairing past harms associated with the transportation sector and ensuring that future investments help heal communities. This Guide explicitly prioritizes safety, beginning with the least protected users, as directed by the USDOT’s 2022 National Roadway Safety Strategy. All practitioners are urged to work toward these goals.

Figure 4-3. Example street designed to move traffic. Figure 4-4. Example street designed for all modes.