Hurricane Reveals Need for Green Infrastructure Defenses in NYC

It has only been six years since our nation learned a valuable lesson in storm preparation: Infrastructure is everything. In 2005, Katrina caused 28 levees to collapse, leaving nearly three-quarters of New Orleans inundated by storm waters.

This past August, New York City’s infrastructure was challenged. Luckily for us, the much less powerful tropical storm Irene did not make a direct hit. However, with State Farm reporting over 360 homeowner claims, 370,000 people being left without power, and politicians playing Texas Hold ‘Em over how to manage the $1.1 billion bill left for FEMA, there are clearly some structural adjustments that the city should make in order to reduce storm damages in the future. It is imperative that city governments update their infrastructure and exhaust measures to protect their residents. For New York City, this means that the city's green infrastructure plan should emphasize the use of landscape swales and Leadership in Energy and Environmental Design (LEED) certified buildings as the best approach for dealing with storms.

One of the weakest links in New York City’s infrastructure is its archaic plumbing system. On average, approximately 27 billion gallons of untreated sewage and waste water discharge into New York Harbor annually, even after as little as a tenth of an inch of rainfall. In the event of a storm, this can lead to high quantities of combined sewage overflows (CSO) seeping into homes and damaging water supply. Threat of CSO has prompted the Environmental Protection Agency (EPA) to order Jersey City to invest more than $52 million in infrastructure upgrades. New York City has been spared equal scrutiny because of its trademark sewage plants and high quality drinking water.

But New York City must not take its sewage plant for granted. Following Irene, Baltimore County reported 12 incidents in which sewage pumping stations overflowed — each incident released between 2,000 and 13 million gallons of sewage mixed with rainwater. With just a little more force, the consequences of Irene could have proven to be dramatic in New York City.

In addition to its outdated plumbing, New York City’s lack of “soft infrastructure” makes it highly susceptible to strong storms in an era where polar ice caps are melting and sea levels are rising. Soft infrastructure, such as wetland edges and swale construction, are tantamount to creating a natural system that will allow the city to withstand greater disasters. Grassed swales, natural structures that are filled with flood tolerant vegetation and erosion resistant marshy lands that can slow the flow of storm waters and filter pollutants, are cheaper and more manageable than the liable gutters and sewers we associate with Gotham. Swales can also be used for snow storage, effectively reducing snow melt peak flows.

One major setback in swale construction is finding space. In this vertical city, the only way to find room is to either build towards the clouds or to recognize what needs to be prioritized and make sacrifices. This may include converting four-lane traffic into three-lanes in order to make more space for an effective swale construction — the tradeoff is more traffic, but the benefits are worthwhile.

While swales are an ideal approach, there are other feasible green initiatives that can save the city from storms, improve air quality, add to aesthetics, and acquire LEED certification and federal dollars through incentive programs. Green roofs have proven to reduce and delay storm water runoff and recycle resources into the environment through transportation and evaporation. With the ability to soak in and filter 70% to 90% of the precipitation that falls on them during the summer and 25% to 40% during the winter depending on the vegetation that is used, green roofs are an ideal solution for New York City.

But we shouldn’t wait until a major storm or for EPA to scold us to do what is smart — the New York City Green Infrastructure Plan should adamantly reach out for the state to fund much needed change. Until there are more green roofs and swales, cities cannot say that they’ve taken all viable measures to optimize their defense against natural disasters.

Photo Credit: Wikimedia Commons