The Best Road Safety Plan is a Good Land Use Plan: Current and Promising Roles for Land Use Planning in Realizing a Vision Zero Future

THE BEST ROAD SAFETY PLAN IS A GOOD LAND USE PLAN: CURRENT AND PROMISING ROLES FOR LAND USE PLANNING IN REALIZING A VISION ZERO FUTURE

ABSTRACT

Patterns of land development, including the density, diversity, design of land uses, and the accessibility of destinations in communities strongly influence travel speeds and travel mode choices, both of which influence the likelihood and severity of traffic injury. In this descriptive study, we explored the degree to which local and regional transportation safety plans intended to eliminate serious and fatal road injury (Vision Zero) integrated land use plans, planners, and ordinances. We examined 31 United States Vision Zero plans published through mid-2019. Results illustrate that about half of the Vision Zero plans involved land use planners in plan development and considered planners responsible for implementing certain actions outlined in the plans, one-fifth of plans referenced land use in the context of improving road user safety along municipalities’ transportation corridors, and one-tenth of Vision Zero plans referenced municipalities’ small area plans. Vision Zero plans more commonly referenced specific land use ordinances and Complete Streets policies. We conclude with a call to better integrate Vision Zero, land use planners, and land use planning.

INTRODUCTION

By and large, the risk of injury for road users increases in tandem with the number and speed of motor vehicles on the road network (Ewing and Dumbaugh, 2009; Marshall, 2018). Yet, despite collectively driving fewer miles throughout the COVID-19 pandemic (Heintzelman, Filippelli, and Lulla, (2021), in 2020, an estimated 38,680 people died in motor vehicle traffic crashes in the United States (US) (National Highway Traffic Safety Administration, NHTSA 2021). This represents the largest number of deaths since 2007, and a 7.2 percent increase compared to 2019 (NHTSA, 2021). Scholars attribute the recent elevation in road injury to higher travel speeds along less congested roadways during the pandemic (Chang and Miranda-Moreno, 2020; Polzin, 2021).

With often long travel distances between origins and destinations in U.S. communities and the relative attractiveness of motor vehicle travel to cover these distances, urban sprawl is strongly predictive of higher travel speeds and rates of serious and fatal traffic injury (Ewing, Hamidi, and Grace, 2016; Yeo, Park, and Jang, 2015). Moreover, as recent case examples (e.g., Yin and Zhang, 2021; Chen and Shen, 2019) and international comparison studies suggest (Buehler & Pucher, 2021), land use ordinances, practices, and regulations play a sizable role in influencing these travel speeds and overall traffic injury risk through a number of additional mechanisms. For example, urban land use decisions determine the density of intersections via block lengths and development-level parking requirements (Guerra, Dong, and Kondo, 2019; Merlin, Guerra, and Dumbaugh, 2020; Manville, Beata, and Shoup, 2013; Yin, Shao, and Wang, 2018), the diversity of residential and commercial development (Graham and Glaister, 2003; Stoker, et al, 2015), the human-scale design of streetscapes (e.g., building setback requirements, establishing commercial areas along high-speed arterial roads) (Dumbaugh, Li, and Joh, 2013), and the accessibility of destinations for people of all incomes, ages, and abilities (Xie, An, Zheng, and Li, 2019). Each of these so-called “D-land use variables” contribute to shaping the amount of motor vehicle traffic, the degree of walkability, and the level of injury protection for all road users in local areas and entire regions (Park, Ewing, Sabouri, and Larsen, 2018).

Given the staggering influence of land arrangement decisions on road users’ safety, one might expect land use planners, land use plans, ordinances, and regulations prominently featured in municipalities’ roadway safety efforts, including in cities’ current Vision Zero plans. Vision Zero, an initiative adopted in multiple European cities beginning in the 1990s and more recently adopted in several US cities, is “a strategy to eliminate all traffic fatalities and severe injuries, while increasing safe, healthy, equitable mobility for all” (Vision Zero Network, 2018). Vision Zero recognizes that road traffic injuries and deaths are complex problems, and that implementation of sustainable solutions requires multidisciplinary stakeholder involvement, including a critical role for land use planners.

Given the rapid adoption of Vision Zero across the US as a best practice approach for improving the safety and livability of communities, the objective of this descriptive study was to explore the role of land use planning in this approach. Specifically, we sought to examine the extent to which current Vision Zero initiatives engage with land use planners, integrate land use plans, and consider planning-related policies in developing Vision Zero plans. Through an examination of Vision Zero plans from across the US, we sought to answer the following research questions.

RESEARCH QUESTIONS

1. How involved were land use planners in the development of Vision Zero plans in the US between 2014 and mid-2019?

2. Among the Vision Zero plans published between 2014 and mid-2019, how often did these plans reference land use plans?

3. Which specific land use policies, if any, were discussed or proposed in Vision Zero plans?

4. To what extent did Vision Zero plans consider land use planners responsible for implementing plan articulated policies, procedures, and countermeasures?

METHODS

As part of a Collaborative Sciences Center for Road Safety (CSCRS) 4 -sponsored study on Vision Zero implementation in the US, our team identified and content analyzed(i.e., abstracted) publicly available US municipalities’ Vision Zero plans (n=31)through mid-2019. We used a robust search procedure, which included routine searches for Vision Zero plans via Google’s search engine; communication with the director of the Vision Zero Network, a national non-profit committed to sharing best practices and lessons from Vision Zero communities across the U.S. and cross-referencing with their tracking of Vision Zero communities across the country; and communication with our team and Center’s extensive network of road safety partners from across the country to ensure complete capture of plans.

We developed an extensive Vision Zero plan abstraction tool with more than 200 elements, allowing our team to manually extract key characteristics systematically and consistently from all plans. The framework used to develop the Vision Zero plan coding tool was based on general elements of high-quality element plans from the literature (Norton, 2008), prior assessments of pedestrian and bicycle plans (Evenson, 2011), and inquiring from safety experts with backgrounds in planning and pedestrian safety. From this framework, we developed an extensive coding tool that identified elements of plans to abstract. The tool went through several rounds of review by researchers on the team and external reviewers affiliated with the CSCRS to ensure clarity and completeness of elements abstracted. Data abstraction was performed for each plan by two trained abstractors with any disagreements resolved by discussion between the two abstractors or at a larger team meeting between all abstractors. Abstraction was performed between 2018 and 2020. 5

We abstracted and assigned stakeholders from their job title or organization ascribed to in the plan. In most plans, specific people were listed but, in some plans, only supportive organizations were identified. In this study, we borrowed from LaGro (2005) to define land use plans as those documents which guide the geographic location of proposed activities, infrastructure, and other site-specific physical improvements. In the following sections, we describe stakeholder groups listed in plans, which we interpret as being involved in developing their Vision Zero plans; the municipal- and state-level planning initiatives referenced in Vision Zero plans; the specific policies, procedures, and countermeasures proposed in the plans to realize a future with zero serious and fatal traffic injuries; and those stakeholder groups considered responsible for implementing the articulated safety-oriented policies, procedures, and countermeasures. We provide counts and percentages by category within each of these elements.

RESULTS

Of the 31 Vision Zero plans reviewed between 2014 and mid-2019, one-third of these plans were published between 2014 and 2016 (n=10), and two-thirds were published between 2017 and mid-2019 (n=21), the most recent year included in this study. The 31 plans in this study included 28 developed by municipalities, two by counties, and one by a Metropolitan Planning Organization (MPO). The median population of the municipalities with Vision Zero plans was nearly 600,000 residents, with a maximum of more than 8 million and a minimum of fewer than 30,000. Among the 28 municipalities in this study, 11 were located in the West U.S. Census region, eight were in the South, six were in the Northeast, and two were in the Midwest. The two counties and single MPO in the study were all located in the South US Census region with populations ranging from one to three million residents.

Involvement of planners and land use plans in Vision Zero

Land use planners were involved in about half of Vision Zero plan development, as were regional transportation planners, social justice and civil rights groups, and private sector groups (Figure 1). More commonly involved groups included law enforcement, who were included in nearly all examined. Vision Zero plans, followed by schools, public health agencies, representatives from the mayor’s office, city council members, or city managers, and “other” kinds of stakeholders (≥70% for each). The other category included a variety of groups not listed in Figure 1, such as aging, parking, and technology advocacy groups. Most of these groups were either community-based or governmental-based groups.

Figure 1. Stakeholders involved in the development of Vision Zero plans (n=30). 6

Only private health organizations, parks and recreation department staff, district attorney’s offices, emergency medical services staff, foundations, environmental nonprofit organizations, and local chambers of commerce were involved in fewer Vision Zero plan development efforts than land use planners, each featured in the development of one-third or less of Vision Zero plans.

Despite land use planners’ involvement in developing about half of the Vision Zero plans, land use plans were not routinely referenced in Vision Zero plans. Comprehensive land use planning documents were referenced in fewer than 10 percent of plans). In slightly more plans (12.9%), sub-municipal plans were referenced (e.g., neighborhood, subdivision, area-level plans). Far more Vision Zero plans referenced modal transportation plans (e.g., bicycle or pedestrian plans), and 29 percent(n= 9) of Vision Zero plans mentioned their states’ Strategic Highway Safety plans. Finally, fewer than 10 percent of Vision Zero plans mentioned plans pertaining to parks and recreation, open space, and greenways(Figure 2).

Specific land use-related policies, procedures or countermeasures proposed

Whereas fewer than 10 percent of the abstracted Vision Zero plans referenced comprehensive land use plans, all abstracted Vision Zero plans included the proposed use of land use ordinances (subdivision ordinances, zoning, and/or unified development ordinances (UDOs) as promising policies to achieve Vision Zero (100%; n=31)(Figure 3). Land use policy was also indirectly featured in at least two-thirds of Vision Zero plans by reference to a Complete Streets policy (67.7%; n=21), unique types of land use ordinances (12.9%; n=4), or car parking (e.g., eliminating minimum parking requirements)and priced parking policies (12.9%; n=4).

Figure 2. References to planning initiatives in Vision Zero plans’ traffic safety analyses (n=31).** Green bars represent land use-related plans.

Land use planners’ role in accountability for Vision Zero implementation

A total of 27 (87%) Vision Zero plans identified persons or agencies accountable for implementing plan-outlined actions. Similar to their frequency of involvement in developing Vision Zero plans, land use planners were considered accountable for implementing plan-outlined policies in about half of the abstracted plans (54.8%) (Figure 4). More commonly accountable agencies and organizations included law enforcement, schools, engineering/public works, transportation planning departments, and other groups (e.g., department of motor vehicles (DMV)). Additional groups referenced in about half of the abstracted plans included state and regional transportation planning agencies, local fire departments, and public health agencies.

DISCUSSION

In our analysis of 31 Vision Zero plans collected from across the US and published between 2014 and mid-2019, we found that in about half of the jurisdictions, representatives of local land use planning departments were involved in Vision Zero planning and implementation and considered accountable for implementing planned Vision Zero policies and interventions. Interestingly, municipalities’ exploration of traffic safety patterns seldom involved examining their comprehensive land use plans or open space plans. Instead, land use planning dovetailed with traffic safety analysis in the more circumscribed contexts of sub-municipal level plans (e.g., neighborhood, subdivisions, or other sub-municipal areas) and along municipalities’ transportation thoroughfares or corridors.

Figure 3. Specific policies, procedures, or countermeasure proposed in Vision Zero plans (n=31).** Green bars represent land use-related policies, procedures, or countermeasures.

Where land use factors came into play with Vision Zero planning was in the sphere of safety-enhancing policies, procedures, and countermeasures. Across all abstracted Vision Zero plans, land use ordinances (e.g., subdivision ordinances, UDOs, and zoning codes) were proposed as means of advancing Vision Zero goals. Additional land use implementation tools included unique types of ordinances (e.g., access management, alcohol outlet density policies), car parking (e.g., eliminating minimum parking requirements, market-pricing parking), as well as Complete Streets policies, which often seek to harmonize transportation and land use to support safe, multi-modal travel (Schneider, 2018).

One conclusion that could be drawn from this analysis is that between 2014 and mid-2019, publicly available Vision Zero plans favored the employment of specific land use policies (e.g., UDOs, elimination of presumptive parking minimums, small-area plans) over the integration of Vision Zero with comprehensive land use plans. Yet considering the complex nature of traffic injury, safety planning should transcend its reliance on circumscribed interventions and shift toward aligning systems toward providing safe mobility and access for all road users (Naumann, Sandt, Kumfer, LaJeunesse, Heiny, & Lich, 2020). A foundational part of this alignment is coupling comprehensive transportation and land use development (Xu, Wang, Ding, & Liu, 2020).

Vision Zero efforts in North Carolina and in numerous municipalities across the U.S. are beginning to embrace a more multidisciplinary, coalition-based approach to support this necessary alignment work. In North Carolina, our team has developed a statewide Vision Zero support model that involves regular coaching, intensive team-based trainings, and peer information exchange. This program (currently used with 8 North Carolina Vision Zero communities) aims to 1) strengthen and diversify Vision Zero coalitions, supporting involvement and alignment of multiple perspectives including land use planners; 2) support Vision Zero communities in overcoming barriers to Vision Zero planning and implementation; and 3) accelerate knowledge and skill-building focused on Vision Zero principles, including in equity and authentic community engagement. We documented increases in local adoption of Vision Zero resolutions and action plans, as well as robust injury risk assessments, growth in the sectoral diversity of local Vision Zero coalitions, increased implementation of Vision Zero strategies, and a steady movement of Vision Zero-adopting municipalities from Vision Zero exploration to implementation stages. Further testing of this model is needed to determine the extent to which it improves road safety outcomes and the extent to which it successfully supports necessary alignment work among land use planners and other critical coalition partners.

As with all scientific endeavors, this study has limitations. First, while we developed a robust procedure for gathering Vision Zero plans across the U.S., it is possible that we may have missed some plans published during the study time frame, particularly if they were not readily available online. Second, our analysis is limited to what is included in Vision Zero plans. Therefore, it is possible, for example, that a municipality included land use planners or land use planning documents in their Vision Zero plan development but may not have mentioned it in their plan documentation. We would expect such instances to be uncommon given the widespread practice of recording key partners and documents considered in these Vision Zero plans. Third, we did not abstract the various types or content of plans available in municipalities, counties, or the MPO in this study (e.g., land use, bicycle, pedestrian, etc.); therefore, the failure to mention a plan may also be because the plan was not present in the community, or it existed but was not cross-referenced. Fourth, based on the plan abstraction only, we were unable to account for the level of involvement of the stakeholders in the plan, and thus expect wide variation in this regard.

Taken together, Vision Zero and land use planning tended to intersect in the realm of land use ordinances (e.g., UDOs, car parking provision) and Complete Streets policies. We consider this a solid first step. For example, ordinances which establish rules around the “D-land use variables,” such as building setbacks and heights, permissible uses of land in specified locations, block length standards, driveway densities, and the provision of dedicated facilities for pedestrians, bicyclists, and transit users can greatly inform municipalities’ experiences with traffic injury. However, specific safety-implicating ordinances and policies are simply a part of broader planning and comprehensive land use dynamics. Unlike codified ordinances and policies, the act of collaborative Vision Zero planning and integration with comprehensive land use planning has the potential to support much broader alignment in several ways. It can serve to bring the community together toward a common cause, allow for open discussion of contingencies for political priority or funding shifts, support development of evaluation and monitoring measures to promote accountability and enhance cross-agency coordination, accelerate learning around best practices in intertwined land use and transportation safety, and much more (LaJeunesse, Naumann, Sandt, Spade, and Evenson, 2020). As municipalities update their Vision Zero plans and more join the growing network of Vision Zero-adopting communities, transportation safety and land use arrangements will be included as critically linked and essential to planning for healthy communities.

ACKNOWLEDGMENTS

This project was supported by the Collaborative Sciences Center for Road Safety (roadsafety.unc.edu), a United States’ Department of Transportation National University Transportation Center (award # 69A3551747113). The UNC Injury Prevention Research Center is supported by an award (R49/CE0042479) from the Centers for Disease Control and Prevention. The content is solely the responsibility of the authors and does not necessarily represent the official views of the funding agencies.