Abstract
This study evaluates the effectiveness of Speed Safety Camera (SSC) deployments in reducing traffic speeds through four interstate work zones in Indiana in accordance with Indiana State Law House Enrolled Act (HEA) 1015. The initial deployment of SSC was along interstate I-70 in August 2024, with deployments on I-69, I-465, and I-65 subsequently following in 2025. To evaluate the impact of SSC deployments in Indiana, connected passenger car and connected truck data was used to quantify the change in speed characteristics before and during the SSC deployments. Approximately 100 million passenger vehicle records and 3 million commercial truck records were analyzed. That connected vehicle data was used to count the number of spot speeds, at 0.1-mile intervals, that were 11mph or more over the work zone speed limit over the entire work zone. The length of those study segments ranged from 3 to 10 miles. Across 443 SSC deployment days between August 14, 2024 and July 11, 2025, the study found 34% reductions on average in the percentage of passenger vehicle spot speeds exceeding the work zone speed limit by 11mph or more on weekdays between 6AM-6PM. For commercial trucks, there was a 41% reduction across the study sites.
Keywords
work zone, speed control, speed enforcement, speed cameras, connected vehicle data, performance measures, work zone safety
Report Number
FHWA/IN/JTRP-2025/33
SPR Number
4933
Sponsoring Organization
Indiana Department of Transportation
Performing Organization
Joint Transportation Research Program
Publisher Place
West Lafayette, Indiana
Date of Version
2025
DOI
10.5703/1288284318595
Recommended Citation
Desai, J., Sakhare, R. S., McGregor, J., Sturdevant, J., & Bullock, D. M. (2025). Worksite speed control system (WSCS) (Joint Transportation Research Program Publication No. FHWA/IN/JTRP-2025/33). West Lafayette, IN: Purdue University. https://doi.org/10.5703/1288284318595
SPR-4933 Technical Summary