The NYC area is still reeling from the devastating storm that hit on October 29, 2012, and it will certainly take some time to heal the scars.
The city has designated Zones in danger of flooding and urgently implored residents to evacuate Zone A areas well ahead of the landfall of the storm to prevent loss of life. Nevertheless, losses have been tremendous.
Many have called for the abandonment of the most flood prone areas. This is the most intuitive response, especially in view of the millions of dollars (now billions) that taxpayers are giving to help other taxpayers rebuild in the danger zones.
We have many examples to show us the folly of rebuilding where the floods will come: the Missouri and Mississippi Rivers in 1993 and 1995, and New Orleans before and after Hurricane Katrina. There was pressure to stop building in flood areas and pressure to rebuild in flood areas. In NYC, the pressure to use all available land and even create more land out beyond the shorelines is so great that it seems futile to deny that possibility. However, to build back the same vulnerable facilities as before would be terrible.
What can we do now to prevent something similar in devastation from recurring?
Certainly, we have read many ideas, especially since Sandy hit. They include tremendous sea barriers to stop the surge from coming into the harbors (similar to London’s Thames Barrier or Rotterdam’s surge barrier), or rebuilding huge wetland areas and barrier islands to buffer the force of a storm beyond our current shoreline. The MTA is considering huge inflatable balloon plugs to be deployed at multiple points along subway and vehicular tunnels, to prevent stormwater from rushing in. These are ideas that would take many years, even decades, to fully implement; in the meantime, we must act.
For new construction, many measures have already been tested and employed to protect buildings from flooding. Battery Park City, though in Zone A, was for the most part built up from adjacent city grades, with parking garages on the lower levels. Most buildings there did not lose power. In Brooklyn’s South Marine Terminal, a new recycling plant also in Zone A which was planned six years ago, escaped the flood around them because they planned in extra fill to raise the facility above floodwaters, far exceeding Code requirements. In Long Island City, Queens, a new development in Zone A specified a higher fill than required and no basements, in addition to a list of other precautions that saved the building from damage.
For new construction and for retrofitting existing buildings, here are some of the other specifications that could be widely applied.
- install mechanical and electrical systems on higher floors instead of basements;
- if the systems are already in basements, find a way to isolate them with watertight enclosures, and add backup systems elsewhere higher up;
- for basements and underground garages, provide floodgates at entry ramps and battens for other openings;
- in high-rise buildings, there is a growing demand for backup electrical generators that can handle essential needs, like elevators, water and fuel pumps;
- fuel tanks will need to be in watertight containers, with pumps and valves above the flood line;
- smaller frame structures along the beaches will need to be built up on engineered stilts, to get living spaces above the floodline (this has been a requirement on many shorelines and riverfronts for many years, and has saved many homes);
- larger buildings may choose to store their own sandbag supplies and portable generating equipment;
- in some areas it may be feasible to build levees to hold back waters, as New Orleans has done;
- revise zoning laws to encourage passive recreational uses in shoreline parks, designed as levees, wetlands, and buffers to storms.
We will surely experience more storms. Let’s get ready for it!
