Understanding Trends in Stormwater Inspection Reports Leading to Recurring Corrective and Urgent Maintenance Issues: Case Study for the Virginia Department of Transportation

Stormwater best management practices (BMPs) are critical to meet regulatory goals for water quality and flood control. As these systems age, it is important to quantify their performance over time and identify the factors that influence the degradation of specific assets. This study explores these challenges through the Virginia Department of Transportation (VDOT) as a case study. As of this study, VDOT maintains a growing inventory of 2,547 BMPs and conducts periodic inspections of these BMP assets. Analyzing 17,874 of these inspection reports from 2020 to 2024, we identify BMPs that have persistent maintenance needs and explore how those issues vary across different environmental and geographic conditions. The findings show that 45% of BMPs have had at least one maintenance issue required as a result of an inspection in at least three of the five years analyzed. This drops to 15% of the inventory when considering only BMPs that required either corrective or urgent maintenance activity in three of the five years. Despite being only 15% of the inventory, these BMPs accounted for over 70% of all corrective and urgent maintenance issues required across all 2,547 BMPs. Results also reveal spatial variation in key corrective issues such as vegetation overgrowth, erosion, and blockage at the inlet and outlet pipes. These findings suggest that while corrective issues for BMPs may be predictable based on inspection and spatial data urgent issues are more difficult to anticipate. The study offers a framework that other agencies with large BMP asset inventories can adopt to achieve long-term BMP performance.