Sea Level Rise, Storm Surge, and Sewage Spills

Climate Central raises the issue.

Sewage treatment plants are usually placed near water in low-lying areas so that sewage can be piped to the plant via gravity and treated sewage can be easily discharged into receiving waters. These key factors in plant locations make them especially vulnerable to storm surges and coastal flooding. Compounding the inherent risk of their low-lying locations, many treatment plants have expansive, underground labyrinths of pipes, holding tanks and pumps that can remain waterlogged and incapacitated long after floodwaters recede. They also typically discharge their treated wastewater through large underwater pipes, which can cause facilities to flood from the inside as waters rise, long before the surface water levels overrun the outside of the structures.


Six months after Sandy, data from the eight hardest hit states shows that 11 billion gallons of untreated and partially treated sewage flowed into rivers, bays, canals, and in some cases, city streets, largely as a result of record storm-surge flooding that swamped the region’s major sewage treatment facilities.

One third of the overflow (3.45 billion gallons) was essentially untreated raw sewage.

94 percent of the spilled sewage, well over 10 billion gallons, was the result of some form of damage caused by coastal flooding. In some cases, Sandy’s storm surge simply flooded treatment plants and pumping stations, while in other cases a combination of power outages and flood conditions shuttered facilities or caused major diversions of sewage into receiving waters.

I’ve always wondered about this – people talk a lot about property damage from tsunamis and storm surges, but they don’t seem to talk about the pollution and detritus, the Fukushima event being an obvious exception.

This report reinforces my suspicion that drastic pollution can result from coastal inundation. Conceivably cities in wealthier and more civilized countries will manage an organized retreat, leaving an objective way to address the vexing question as to whether Florida is a civilized country. But what happens to the ocean when Calcutta, for example, is permanently inundated?

Read the whole article. (By the way, the animation in the interactive graphic bothers me a lot. What a pointless, information-free use of the time dimension. It’s fourth dimensional chartjunk.)


Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.