Combatting Storm Surge Flooding in Lower Manhattan and its Effects on the NYC Subway Kayde Cox, Emily Jennings, Daniel Schwartz, and Sylvia Zaki, Queens College What is the problem? What’s the plan? What have we decided? What can we do? References Which strategy is better? Plug the drain! 1. Plug the drain!  With specially engineered inflatable plugs that will fill a tunnel  Will act as a plug would in a sink, not letting water get through, preventing flooding due to storm surge  Inflate in under three minutes  Need minimal adjustments in order to fit each tunnel  Cost: About $400,000 per plug  Figure 1 breaks down the infrastructure  Needs further development  Strategies to safeguard subway tunnels will focus on: Installing subway plugs prior to periods of predicted heavy storm surge  Cost-efficient: $400,000/plug  Simple to implement: 30-minute pressurization time and fits to contour of tunnel  Durable: Can withstand 500,000 pounds of force Elevating subway grates 6-18 inches above the sidewalk  Unnecessary grates can be sealed  Elevated grates already in use in Hillside Avenue zone  216 raised, 353 sealed—cost valued at several million  Cost efficient, aesthetically pleasing  Diverts moderate floodwater and rubbish from tunnels  Further research needs to be conducted about the feasibility of integrating elevated subway station entrances into lower Manhattan  Effective long-term strategy for waterproofing stations  Already in use in Taipei and Bangkok  Will allow uninterrupted subway service throughout category 2 hurricanes and less intense storms  Storm surge flooding events in lower Manhattan that normally occur once every hundred years are expected to occur every three to 20 years  This increase in flooding is exacerbated by climate change  East River subway tunnels below Canal Street are vulnerable to flooding  Without prior preparation, complete flooding of these tunnels could take 29 days to recover from  This would cost New York City approximately $23 million per day that the subway system is shut down GOAL: East River subway tunnels must be completely protected from flooding in the event of a category two hurricane or lower by the year Keep this color and font, just put in the references 2-3 lines tops StrategiesProsCons Plugs Cheap Effective Is not fully developed yet May need to be altered for each tunnel Elevated Subway Grates Cheap Effective Stylish Will not take long to implement Provides seats and bicycle racks May not be effective in the event of a 100 year storm occurring Elevated Subway Entrances Station entrances inaccessible to floodwaters Allows for subway functionality, if floodwaters are shallow enough Space limitations Integration issues Accessibility issues Price & time needed for construction: unknown Figure 2: Created by Rogers Marvel Architects, these elevated subway grates were designed to divert rubbish and storm surge flooding from entering subway tunnels through street level grates. The grates stand 6-18 inches high (depending on flood risk) and can be found in Astoria and Hillside Queens. Elevated subway grates 2. Elevated subway grates  Increase susceptible subway station entrances’ lowest critical elevation to 20 ft. through a combination of structural elevation and the use of flood gates.  Further investigation is needed to determine cost, station placement and/or integration with neighboring structures, and to figure out accessibility issues.  Implementation by necessity: More susceptible stations are elevated first.  A survey of every station’s LCE and proximity to the shore is needed to determine order of implementation Elevated subway entrances 3. Elevated subway entrances  Diverts water from entering directly into subway grates  Diverts rubbish from falling through into the subway tunnels  Can serve as seats or bicycle racks to be more aesthetically pleasing  Are a short term solution because they will not stop flooding if a 100-year storm event were to happen  Increase subway grates 6-18 inches above the sidewalk  Seal up subway grates that are not necessary to stop rain from entering at all Completely protect the 4 and 5 train subway tunnels from flooding by 2028 Completely protect the R train subway tunnel from flooding by 2045 Completely protect the 2 and 3 train subway tunnels from flooding by 2062 Completely protect the A and C train subway tunnels from flooding by 2080 Effective January 2013, starting in Battery Park, begin to replace necessary subway grates with elevated grates. Seal up grates that prove to be unnecessary. Repeat this process moving uptown until we reach Canal Street. Conduct a survey in June 2014 of every lower Manhattan train station’s proximity to the shore to determine order of implementation. Stations that are most susceptible to flooding will be the first stations to be elevated. Aim to have research pertaining to the plugs completed by June 2015, then start to equip subway tunnels with the plugs by 2016, placing subway stations located closest to the water at a higher priority. By January 2016, establish a training program to teach MTA employees to effectively use the inflatable plugs. Have researchers evaluate lower Manhattan from and the changes that must be made to accommodate elevated subway entrances. Figure 1: Diagram of the Department of Homeland Security’s development of the plug to stop flooding in subway tunnels. Figure 4: MTA map of the flooded subway tunnels during Hurricane Sandy Figure 3: An elevated MRT station in Bangkok, Thailand defends the subway system from floodwaters during the 2011 monsoon season. Subway stations are elevated 1.20 meters above street level and are equipped with flood barriers, adding another 1.50 meters of protection.