A Surrogate Video-Based Safety Methodology for Diagnosis and Evaluation of Low-Cost Pedestrian-Safety Countermeasures: The Case of Cochabamba, Bolivia

Abstract

Due to a lack of reliable data collection systems, traffic fatalities and injuries are often under-reported in developing countries. Recent developments in surrogate road safety methods and video analytics tools offer an alternative approach that can be both lower cost and more time efficient when crash data is incomplete or missing. However, very few studies investigating pedestrian road safety in developing countries using these approaches exist. This research uses an automated video analytics tool to develop and analyze surrogate traffic safety measures and to evaluate the effectiveness of temporary low-cost countermeasures at selected pedestrian crossings at risky intersections in the city of Cochabamba, Bolivia. Specialized computer vision software is used to process hundreds of hours of video data and generate data on road users' speed and trajectories. We find that motorcycles, turning movements, and roundabouts, are among the key factors related to pedestrian crash risk, and that the implemented treatments were effective at four-legged intersections but not at traditional-design roundabouts. This study demonstrates the applicability of the surrogate methodology based on automated video analytics in the Latin American context, where traditional methods are challenging to implement. The methodology could serve as a tool to rapidly evaluate temporary treatments before they are permanently implemented and replicated.Sustainability 2019, 11, 4737 2 of 22 However, pedestrians, particularly in low-income countries, are highly vulnerable road users, as they face a higher risk of injury and are involved in a large share of fatal collisions with vehicles relative to other modes [3]. Pedestrians and cyclists represent more than 25% of the fatalities in Latin American countries, with the share rising to more than 50% in some countries (in comparison to 16% of road fatalities in the United States) [4,5]. In the face of increasing pressure on cities associated with rapid urban growth and motorization, road traffic injuries and fatalities, particularly for vulnerable users, are expected to increase [6].While many developed countries have established road safety programs and action plans, (e.g., "Vision Zero"), such programs are often absent or weak in Latin America. Crash data and knowledge needed for designing and evaluating traffic safety programs frequently do not exist or are limited in quality. This is attributed to several factors. Weak institutional arrangements often impede the development and management of adequate crash notification and registration systems. Additionally, government entities frequently lack the economic resources needed for the acquisition of the adequate tools for traffic safety analysis and evaluation. As a result, crash data needed for designing effective traffic safety programs frequently do not exist or are limited in quality with levels of underreporting of traffic incidents estimated to reach as high as 50% [7][8][9][10].Instead of using a reactive crash-based approach, recent developme...

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