Drone-Based Standardized Environmental and Usage Assessment of Parks and Trails

Abstract

We introduce a drone-centric workflow that complements fixed trail cameras to deliver objective, standardized, and scalable assessments of park and trail infrastructure. Traditional human audits, such as PARA and the Boston Block Walk, are labor intensive and subjective and lack the corridor scale perspective needed for comprehensive maintenance planning. Our system addresses this gap by using (i) a multirotor UAV equipped with synchronized thermal and RGB cameras to document surface conditions over vast areas and quantify defect dimensions, and (ii) low-cost fixed cameras to continuously monitor user counts, activity types, and intensity (MET) values. Drone imagery is calibrated via homography to convert pixel measurements to real-world units, and a thermal RGB data fusion pipeline detects cracks, moisture-softened patches, and other defects. A case study on a community tennis court demonstrated a mean absolute percentage error (MAPE) of 11.6% between drone-estimated and tape-measured crack lengths. Along Delaware’s Jack A. Markell and James F. Hall trails, camera-based usage analytics revealed patterns consistent with intercept surveys: ≈ 20% of the users were cyclists and ≈ 98% engaged in recreational activities, while estimating speed-derived METs for walkers, runners, and cyclists. Compared to an 11-mile manual audit that required 26 raters, our approach reduced costs by approximately $4,000 and produced reusable digital evidence. We conclude that drones are the necessary backbone for corridor-scale, time-bounded condition assessments, while fixed cameras remain essential for long-term use monitoring; together, they enable auditable, repeatable, and cost-effective management of urban greenspace.