Subway/Metro

NYCT Performance of Architectural and Engineering Design of Flood Mitigation Measures at Three Locations in the Borough of Manhattan
New York, New York

In August 2007, severe rainfall during the morning rush hour crippled the NYCT Subway system and stranded over 2 million users. Several NYCT stations were flooded and shut down. As a result, the New York Governor’s Office mandated that the MTA eliminate vulnerabilities to flooding of its system within the 36 months. In response, NYCT, in coordination with the MTA, issued several task order assignments to help the agency identify the flood vulnerabilities and develop designs to prevent another catastrophic system failure due to rainfall.

SYSTRA, as part of a joint venture, was selected to address flooding vulnerabilities at three stations in Manhattan and design and implement measures to remedy these vulnerabilities. These stations, along the Broadway – Seventh Avenue Line are located at the 79th Street and 86th Street intersections along Broadway, and at Chambers Street on West Broadway. This first Manhattan task order is the foundation for future improvements as it included significant stakeholder outreach efforts with NYCDOT, the Arts Commission, Parks and Recreation Department, and various agency and community groups to reach agreement on the streetscape improvements proposed, requiring an accelerated approvals process. SYSTRA worked closely with NYCT to coordinate these efforts. This high-profile project moved forward under an aggressive design schedule.

SYSTRA reviewed available NYCT stations, track profiles, and tunnel archive data, coordinated the topographic survey data collection, identified existing vent grates for closure or raising based on flooding vulnerability, and prepared civil and structural design plans for proposed improvements. SYSTRA managed the SES ventilation analysis of tunnel segments under existing conditions and with proposed improvements.