Identifying Environment-Based Risk Factors for Crashes in Fairfax County

When considering the construction and operation of roads, one of the most immediate factors taken into consideration is collision mitigation. It is the hope that by documenting and analyzing these crashes, measures can be taken to prevent more in the future. However, in Fairfax County alone, there have been close to 100,000 recorded crashes since 2017, with the only decrease in crash frequency being attributed to the Coronavirus pandemic in 2019. Excluding said period between 2019 and 2020, the total number of crashes has increased by an average of 3.6 percent per annum. The traditional method for addressing a high frequency of crashes is associating multiple individual crashes to a singular fault (i.e. a faulty traffic light, unpaved road, etc.). While effective, this approach fails to address crashes that occur in less frequent regions, but can still be attributed to a similar cause. Taking data from the Virginia DoT, ArcGIS Pro and Stata were used to compare the relationship between three data points: the road, nearby buildings, and the crash itself. Using combinations of the variables available, multiple correlation algorithms were run in an attempt to identify a common group of characteristics leading to a crash. For instance, in a correlation analysis comparing light conditions and whether a car was speeding, it was found that crashes involving speeding cars were 7.99 percent more common during evening hours where a light source was present than during daylight hours. Currently, the complete compilation of data for this study is ongoing; however, this study’s successful completion could provide more specific research results from findings like the example above. Eventually, we hope this research can contribute to designing safer roads and mitigate problematic road sections.