Protecting New York City's subway stations against future flooding

Arup undertook a feasibility study, and subsequent design, for long-term flood mitigation and resilience for eight stations in Manhattan. Arup’s study revealed that no existing tools or solutions available at the time would fully address the problem the stations faced. In response, Arup collaborated with ILC Dover to develop Flexgate - a fabric-based gate installed at the top of a subway entrance that can be deployed quickly and withstand flooding associated with Category 2 hurricanes.

Flexgate comprises of material used in NASA’s spacesuits and replaces traditional flood barriers, introducing an innovative point-of-application system that eliminates the need for post-storm cleanup. The gate stretches horizontally, completely covering both the entrance and stairwells. 

Following a prototype demonstration for NYCT officials, the Flexgate is now being installed across vulnerable stations across New York’s subway system and different variations of the Flexgate are being developed for vertical-plane application. 

A collaborative effort for flood management 

Arup worked with ILC Dover, a firm known for manufacturing of high-performance flexible materials most often used in the aerospace industry. The team developed a set of specifications to which the prototype would have to perform; factors such as product life span, its load capabilities, and how the device would interact with the in-place infrastructure were taken into consideration during the development process. A specific criteria of the project was that no re-engineering of the existing structures could occur. This required the solution to be seamlessly integrated with the surrounding infrastructure.