Last week, New York City witnessed a brief bout of intense rain it hadn’t experienced in over seven decades. In just a day, New York received a month’s worth of rain. For a city revered for its resilience, the downpour exposed glaring infrastructure vulnerabilities.
When streets turned into streams
The city’s streets transformed into treacherous rivers, submerging vehicles mid-road and flooding basement apartments. The sight was eerily reminiscent of the devastating aftermath of Hurricane Ida in 2021. Such events are no longer anomalies—they’re the “new abnormal” as climate change rages on.
An ill-prepared infrastructure
So, why does New York City drown when the heavens open up? The root cause lies in NYC’s sewer system. Designed to process about 1.75 inches of rainfall per hour, it was overwhelmed by the rain, which came down at a rate of two inches per hour.
Furthermore, impermeable surfaces—pavement and rooftops—intensify the issue. These surfaces don’t allow rainwater to seep into the ground, increasing the runoff that sewer systems have to handle. This issue extends beyond dense urban centers and includes the runoff from highways and parking lots, which challenges sewer systems, often causing severe erosion. Recognizing this, NYC now mandates water catchment systems in new constructions and promotes the incorporation of green roofs.
The domino effect on sewer systems
When the sewer system is inundated, problems multiply. Normally, all sewer pipes channel water to wastewater treatment plants where rainwater and sewage undergo treatment before being released into local waterways. However, when overwhelmed, these plants dump untreated sewage and rainwater directly into waterways, known as combined sewer overflow. This is precisely why warnings against swimming in city rivers post-rainstorms exist.
Worse yet, excessive pressure can cause backflow, where sewage water reverses course into buildings. Not only is this nauseating, but it’s also a severe health hazard.
Silent city officials: Cause for concern
One can’t help but notice the lack of proactivity from New York City officials. Despite the evident chaos, the city’s response was noticeably muted. Residents were left uninformed, and it took a staggering 12 hours before the mayor finally addressed the issue.
Perhaps the most telling sign of the times is this: In past major flood events, a hurricane or tropical storm was often the culprit. But this time, the disaster was caused by a storm without a name, emphasizing the increasing unpredictability of our climate.
As thought leaders in the carbon accounting realm, we can’t stress enough the urgency of climate action. The waters of NYC are sending us a clear message: it’s time to pay attention, adapt, and take action.
1. The New York Times, “Why New York City Keeps Flooding,” https://www.nytimes.com/2023/09/29/nyregion/nyc-sewer-system-infrastructure.html Accessed October 5, 2023
2. NYC Builidings, “Green Roofs,” https://www.nyc.gov/site/buildings/codes/green-roofs.page Accessed October 5, 2023