Port Authority of New York and New Jersey - PATH System Resiliency and Recovery Improvements
In the wake of Hurricane Sandy and the substantial damage done to the infrastructure managed by the Port Authority of New York and New Jersey (PANYNJ), PANYNJ has been repairing and rebuilding infrastructure components to make its PATH transit system more resilient to future Sandy-like storm events. The PATH system, the heavy rail (6 to 12-car trains) rapid transit system linking Manhattan to New Jersey cities and suburban communities, experienced the most severe flooding of any PANYNJ facilities during Hurricane Sandy. The improvements to enhance PATH’s resiliency to storm events are part of a comprehensive system enhancement program to complete storm-related repairs in the short term, and accommodate increased capacity demand in a sustainable, resilient way in the long term.
Hurricane Sandy caused significant damage to the PATH transit system, especially when storm surge flooded major parts of the system with saltwater. After workers pumped millions of gallons water out of the train passages, switches and signals still were not functioning, delaying safe operation of the trains. PATH transit service was completely suspended for over a week after the storm, and full 24/7 transit service was not restored until January, about 3 months after the storm. Since the storm, PANYNJ has continued to identify needed repairs to keep the system functioning properly. In 2014, nearly 2 miles of corroded rail fasteners were replaced to better secure the track bed. Surfaces throughout the PATH system were power-washed and cleaned to remove salt deposits which can decrease the life span of equipment.
After the initial repair work, PANYNJ also began identifying short-term, cross-agency solutions to minimize flood risk to the system. The Port Authority’s engineering department led an effort to identify strategies and needs for building resilience across the system. Strategies identified include the following:
- Immediate flood mitigation strategies – PATH system and other facilities now have in place concrete bin blocks, cast-in-place concrete barriers, and stackable sand-filled barriers, which last about five years as a more temporary measure. In some cases, PATH employees will put barriers in place right before a storm, depending on the vulnerable area’s location and use. For example, PATH identifies which doors will be needed during a storm, and can stack aluminum stop logs (barriers that can be tightened) in front of those that can remain closed as extra flood protection. For roads that are needed as long as possible before a storm hits, water-filled barriers are placed across roadways for last-minute flood protection.
- Flood protection built into future projects – Future projects will consider floodgates, inflatable balloons in tunnels, and elevating electrical and switching equipment above flood levels.
- Power substation upgrades – Substations throughout the PATH system will be replaced with taller buildings, protecting electricity infrastructure and preventing future power outages due to flooding.
- Cost assessment of design options – The team worked to identify viable design options to increase flood protection and maintain electricity generation capacity. As part of this process, the team assessed the need for potential adaptation strategies and the costs of implementing those strategies. They also prioritized the strategies to be implemented to target the most vulnerable portions of the system prior to the hurricane season that followed Sandy.
PANYNJ is also in the process of developing longer-term design solutions to improve overall system resilience. The engineering team has begun taking an asset-specific approach to improve the design of infrastructure and prioritize improvement projects, taking into account life expectancy of each asset and the risk of a flood happening in that lifespan. They also incorporated an assessment of asset criticality, analyzing the importance of the asset from emergency response, business, and regional connectivity standpoints. In the context of flood mitigation, this approach will help PANYNJ determine what kind of measures, such as added elevation to facilities, should be included in the design. PANYNJ adopted Sustainable Infrastructure Design Guidelines in 2009 which require critical facilities to be elevated 2.5 feet above the FEMA 100-year flood level, but after Hurricane Sandy, the agency has determined to consider up to 6.5 feet freeboard depending upon the criticality and lifetime of the asset
The post-Sandy resilience efforts build off previous PANYNJ adaptation projects over the past two decades. For example, PATH engineers and electricians previously analyzed the effects of a 1992 Nor’easter storm that left the Hoboken PATH station flooded, and interrupted commuter service for 10 days. After the 1992 storm, engineers examined what went wrong, and how they could avoid shutdown of service in the future. For example, the 70 year-old water pumps in the tunnel failed to handle the flood volume brought on by the storm In response to the storm, flood gates were installed at Hoboken, and all openings sitting below 100-year flood levels were sealed.
PANYNJ builds and manages a variety of critical transportation assets, including aviation, rail, surface transportation and seaport facilities. The Port Authority Trans-Hudson Corporation (PATH) is a subsidiary of PANYNJ. Funding for these system improvements comes from PANJNY agency funds and $141.5 million in federal aid allocated to PANJNY to repair damage to the PATH system caused by Hurricane Sandy.
This Adaptation Clearinghouse entry was prepared with support from the Federal Highway Administration. This entry was last updated on January 16, 2015.
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