Guidance to Improve Pedestrian and Bicyclist Safety at Intersections (2020)

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10 GUIDANCE TO IMPROVE PEDESTRIAN AND BICYCLIST SAFETY AT INTERSECTIONS Chapter 1: Frame the Process All transportation projects seek to promote and provide for the safety of the public. This chapter describes the first step of the safety identification process, providing an overview of how project scoping and strategy decisions may impact pedestrian and bicyclist safety assessments and countermeasure selection. The focus of this Guide is on how to select and apply pedestrian and bicyclist intersection countermeasures for a given intersection or set of intersections, but it can also be applied to systemic safety across a network or as part of a broader transportation planning process. 1.1 Project Scope The first step in framing the safety identification process is during the development of a project scope that will guide the project through key decision points later on. Project scopes should identify: • A clear project purpose and need; • The project delivery method; • The project limits, including considerations of the intended network connections that are being made within the larger walking and bicycle network; • The land use context, modal priority, and right-of-way constraints; • The types of bicyclists and pedestrians expected to use the facility or network; • A high-level overview of key safety issues to be addressed, including identifying crash patterns where data are available, and considering public concerns where possible; • The budget; and • The level of public support. Ultimately, the project scope will significantly influence countermeasure selection and, in many instances, will limit the available countermeasures that can be realistically considered. 1.2 Project Purpose and Need All projects should have a clear purpose and need that indicate why the project is being undertaken and what the project intends to accomplish. Note the Identify Treatment Options for Creating Safer Intersections Countermeasure Options Final Countermeasure Selection Evaluate Priorities and Assess Trade-Offs and Viability 4566 Analyze Intersection Safety and Identify Issues Identify and Collect the Data for Analysis 2 3 Chapter Chapter Chapter Chapter Chapter Chapter Frame the Process 1Chapter

11 GUIDANCE TO IMPROVE PEDESTRIAN AND BICYCLIST SAFETY AT INTERSECTIONS discussion of purpose and need here is not intended to supplant or supersede guidance for a purpose and need statement as established by the National Environmental Policy Act (NEPA). It is intended for the purpose of identifying pedestrian and bicyclist safety goals for a roadway design or safety project. For the purposes of this Guide, the project purpose and need should clarify how decisions that require an assessment of tradeoffs between mobility and safety will be weighed. This outcome can be accomplished by considering the following questions. Why is this project being undertaken? Is the project in response to community safety concerns, planning studies, or a documented crash history? When assessing safety, the experience and comfort of persons walking and biking at an intersection should be considered along with the crash history. Many communities have pedestrian or bicycle master plans which identify locations with missing or inadequate infrastructure or intersections with safety problems. What is the goal for this project? Is the project goal to provide a basic level of access (e.g., the provision of a sidewalk, crosswalk, pedestrian signal, or bike lane; see Figure 6, left), or to provide a high-quality and comfortable environment for people walking or bicycling (see Figure 6, right)? Is the project intended to revisit the modal priority for the corridor, or to address safety concerns and promote more people walking or bicycling at the location? Because many roadways have been built to facilitate motor vehicle traffic, the existing conditions typically suppress walking and bicycling activity. The provision of basic infrastructure can improve access and safety for existing intersection users. However, if network connectivity or the comfort needs of people walking and bicycling are not also considered, new infrastructure may not encourage or promote more walking or bicycling at the intersection. When the project goal includes increasing walking and bicycling, countermeasures that improve comfort and network connectivity for nonmotorized travelers will need to be considered. What does success look like? Success should be defined for each project goal. For most safety projects, success can be defined by a reduction in crashes. However, given the lower numbers and random nature of pedestrian and bicyclist crashes, it may be desirable to assess safety improvements in the near-term by surrogate safety measures such as user surveys or reports of areas of concern, measures of comfort (e.g., pedestrian or bicyclist level of service or level of traffic stress), or a combination of these. At locations with suppressed walking and bicycling activity, improvements in the facility comfort, reductions in nonmotorized traveler delay, and increases in walking and bicycling activity can be important measures of success. Figure 6.  Example facility disconnected from pedestrian network (left) and connected to existing network (right). Source: Toole Design

12 GUIDANCE TO IMPROVE PEDESTRIAN AND BICYCLIST SAFETY AT INTERSECTIONS 1.3 Project Delivery Method Whether selecting countermeasures under scopes of work that have already been developed, or developing a scope of work to initiate a project, it is important to understand that the project delivery method can constrain the potential countermeasure options. The delivery method can also impact the relative degree of flexibility available to apply engineering judgment when determining project design values. It is critical to understand the difference between nominal and substantive safety when comparing existing roadway design parameters to minimum design standards in policies and guidance documents. Existing roadways which meet minimum standards (nominal safety) may have crash problems (substantively unsafe). Likewise, some existing roadways do not meet nominal safety criteria, but have no record of crashes and are substantively safe to travel on. For projects that seek to improve safety at an intersection, a practical design process focuses on analyzing safety performance histories and identifying community and multimodal safety needs, rather than focusing on meeting geometric design features simply because they do not meet today’s criteria applicable to new construction. The performance of the existing roadway and the project goals (for example, to improve bicycle or pedestrian comfort) should be considered when determining design controls and exceptions. New Construction (4R Projects) New construction projects build roadways on a new alignment (see Figure 7, left). They will generally have the least flexibility in selecting design values but provide the greatest opportunity to install geometric design features which optimize bicyclist and pedestrian safety. Design features which are proven to provide systemic safety benefits should be incorporated into all designs where practical. The full range of countermeasures should be considered in the design of new roadways. The primary limiting factors are right-of-way constraints, budget, and modal priority decisions. Reconstruction (4R Projects) Reconstruction projects rebuild roadways along existing alignments to repair the full depth of the pavement or to add capacity. These projects also include utility repair, replacement, or installation (see Figure 7, right, and Figure 8). These projects generally strive to meet preferred design values but may require the application of design flexibility to work within existing right-of-way constraints. Similar to new construction, all countermeasures should be considered for reconstruction projects, as they typically allow for relocating curbs and installing new utilities such as street lighting or traffic signals. However, some countermeasure options may be precluded due to modal priority decisions, budget, or public support constraints. Figure 7.  Examples of new construction (left) and reconstruction (right). Source: Kittelson & Associates, Inc.

13 GUIDANCE TO IMPROVE PEDESTRIAN AND BICYCLIST SAFETY AT INTERSECTIONS Restoration, resurfacing, or rehabilitation (3R projects) These maintenance projects are the most common project types and involve pavement surface repairs and targeted safety improvements. These projects may limit the use of countermeasures that require modifications to existing curb alignments or utilities. Despite the more limited scope, these projects often present opportunities to implement meaningful, lower-cost countermeasures such as pavement markings, signs, and signal timing changes which can improve safety outcomes. Roadway reconfigurations to implement road diets or add refuge islands will typically be limited to strategies which use pavement markings or temporary materials (e.g., tubular markers, temporary engineered curbing, raised crosswalks). Utility upgrades or traffic operations projects These projects are generally limited to installing, replacing, or upgrading existing utilities (including street lights), traffic control devices, or traffic signal equipment. These efforts may be incorporated into 3R or basic maintenance projects (Type 1R or 2R). 1.4 Project Limits Project limits should be carefully considered in view of the network impact of an improvement with regard to bicyclist and pedestrian safety. Master transportation plans which recommend improvements for people walking and bicycling should be consulted when choosing project limits, because many safety issues can result from the lack of appropriate infrastructure. An analysis of crash data alone can result in project limits which may not result in improved bicycle or pedestrian network connectivity. The provision of connected pedestrian and bicycle networks is critical to encouraging and promoting walking and bicycling, which in turn can improve safety outcomes for users by contributing to a safety-in-numbers effect. A systemic approach to safety should include a network consideration. Additionally, project limits determined based on crash histories may be misleading about the extent of an existing safety problem, given that databases of police-reported crashes historically under-report bicycle and pedestrian crashes, particularly when bicyclists and pedestrians are not severely injured. Hospital databases can provide additional information to identify potential safety problems. Public surveys and road safety audits are common strategies to identify safety issues that should be addressed in safety projects which may not be identified through crash data alone, and can be used to help establish appropriate project limits. Figure 8.  Road diet resulting in pedestrian refuge islands, new crosswalks, and buffered bicycle lane in Seattle, WA (left); and raised crosswalk implemented with roadway restriping to add bicycle lanes and improve pedestrian safety in Washington, D.C. (right). Source: Toole Design

14 GUIDANCE TO IMPROVE PEDESTRIAN AND BICYCLIST SAFETY AT INTERSECTIONS 1.5 Project Context Another key component of framing the process includes being clear about the project’s context— both now and in the future. The project context includes an understanding of the role of land use in influencing roadway user behavior and potential countermeasure effectiveness, clarity about modal priority (e.g., is the project along a key part of the pedestrian and/or bicycle low-stress network, or is it in response to a serious pedestrian safety problem?), and the right-of-way constraints that will ultimately influence countermeasure feasibility. Both master transportation plans (which recommend improvements for people walking and bicycling) and zoning and community plans (which identify the corridor’s future land use context) should be consulted. Context is further discussed in Chapter 5. 1.6 End Users The project scope should also be clear about the intended end users. For example, research is clear that “interested but concerned” bicyclists want to be substantially separated from motor vehicle traffic (see Figure 9 for example), whereas “confident” bicyclists are willing to bicycle in most environments. If the project is intended to cater to less-confident bicyclists, this information is important to know up front so that countermeasure selection can proceed accordingly. 1.7 Safety Strategy (Decision Point) A fundamental project scoping decision is whether the project is intended to recommend countermeasures that react to past crashes (a spot location approach or reactive approach) or if the project is seeking to develop countermeasures to prevent the likelihood of future crashes (a systemic safety or proactive approach). A reactive approach has smaller data needs, as it looks at crash history supplemented by observations in the field. However, this approach assumes past crash patterns will continue into the future and often doesn’t adequately assess the conditions which contribute to crashes and which may be present at other locations that do not yet exhibit crash histories. This type of approach can minimize budget impacts by constraining the locations and crash types to analyze. It can also be easier to justify countermeasures that address a known crash history, which can be helpful for projects that require public support. However, this approach will not reduce the probability of future crashes for pedestrians and bicyclists at nearby intersections with similar characteristics, and treatments at one location may just “move” crashes to another, similar location in the network. Source: Toole Design Figure 9. Example of “interested but concerned” bicyclists.

15 GUIDANCE TO IMPROVE PEDESTRIAN AND BICYCLIST SAFETY AT INTERSECTIONS A systemic approach has larger data needs, as it looks at crash history over a larger area to identify combinations of geometric, operational, and land use characteristics which contribute to crashes. It requires a more intensive initial data analysis to assess these characteristics and establish contributing factors to crashes. A systemic safety approach can also result in countermeasures being applied at more locations than a reactive approach, which can increase project costs and project limits. The benefit of a systemic approach is that it aims to address locations with problematic combinations of features before crashes occur, thus working proactively to address safety. This approach will also likely benefit pedestrian and bicyclist comfort and perceived safety, by virtue of addressing issues or problematic combinations of features that are known to be associated with crashes. This proactive approach is critical to reaching bold safety goals such as Vision Zero. Both of these approaches and their related data needs are discussed further in Chapters 2 and 3. 1.8 Financial Considerations The availability and source of funding can significantly affect the type of countermeasures available for consideration. Projects which have relatively low budgets will not likely be able to include countermeasures such as curb modifications, new signals, or structures. Improvements may be reduced to lower-cost pavement markings or traffic control signs. Budgets should be estimated with consideration of the bicycle and pedestrian network goals, the scale of the safety problem, the need to modify the existing environment, and the need to engage the public. Some funding sources place restrictions on the types countermeasures that can be funded, while others are structured to rank projects for funding based on benefit–cost analyses. One of the primary funding programs to address safety issues is the Highway Safety Improvement Program (HSIP), which may be directed toward all public roadways, including non-state–owned roadways. States also have State Highway Safety Plans (SHSP) which may supplement HSIP funding. These programs can help an agency identify, assess, prioritize, and fund safety improvement projects based on benefit– cost analyses of countermeasures. However, a significant shortcoming for bicyclist and pedestrian countermeasures is the potential for “non-ranking,” which may result when a benefit–cost ratio cannot be computed due to a lack of relevant crash modification factors (CMFs). Because research on the effectiveness of pedestrian and bicyclist countermeasures is recent and ongoing, pedestrian- and bicycle-specific CMFs are only recently emerging. The number of pedestrian CMFs greatly exceeds bicyclist CMFs, but both are challenged by a lack of pedestrian and bicycle count data needed to assess crash risk and to rate the quality of existing CMFs (see Section 3.3 for additional detail). To overcome this limitation, some states set aside a portion of HSIP or SHSP funding to specifically address bicyclist and pedestrian safety needs. Practitioners are encouraged to explore the available funding options to understand how they may impact countermeasure selection. Some safety countermeasures, such as protected left turns, road diets, paved shoulders, and raised median islands produce quantifiable benefits for motorists as well as for pedestrians and bicyclists. By reducing crashes for all modes, such countermeasures can reach high benefit–cost ratios while improving pedestrian and bicyclist safety. 1.9 Public Support The countermeasure selection process should be informed by good-faith public outreach to allow the community and ultimate end-users to express their preferences, hopes, and concerns about safety problem(s) and potential solutions. In many cases, projects which improve pedestrian and bicyclist safety also result in safety improvements for motorists and help meet other community livability goals. Working together with the public from an early point in the process will greatly increase the likelihood of a successful outcome; this topic is covered further in Chapter 5. At this point, the project scope has been fleshed out with information relevant to improving pedestrian and bicyclist safety and a decision has been made about pursuing a reactive or proactive safety improvement strategy. Step 1 of the safety identification process is complete.