Town of Cortlandt, Westchester County, New York

This $24 million NYSDOT Region 8 project transformed the flood-prone Annsville Circle intersection of U.S. Route 6/U.S. Route 202 and U.S. Route 9 into a modern roundabout, improving safety, mobility, resiliency, and pedestrian accessibility for approximately 31,000 daily travelers. The corridor experienced frequent flooding, resulting in recurring roadway closures and significant traffic disruptions. The project raised roadway elevations by as much as seven feet, enhanced pedestrian connections, and improved overall traffic operations.

The design incorporated innovative and sustainable engineering solutions, including Lightweight Foamed Glass Aggregate (LFGA), one of the first applications of the material on a NYSDOT project. Manufactured from recycled glass, LFGA reduced loading on weak underlying soils while minimizing settlement concerns. Geosynthetic Reinforced Soil (GRS) technology was also utilized to improve stability, accelerate construction, and reduce impacts to the traveling public. The project received a regional America’s Transportation Award from AASHTO for Best Use of Technology and Innovation.

Services Provided:

  • Survey and mapping
  • Traffic engineering and analysis
  • Preliminary and final highway and roundabout design
  • Design Approval Document preparation
  • Utility coordination
  • Construction support services

Awards:

  • 2026 Environmental and Water Resources Project of the Year Award Recipient

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