New York City is about to open the world’s largest UV disinfection plant in a couple of months, which will treat roughly 5 billion gallons per day. That’s a lot of water. That’s also a prime reason why I always found the evil plot at the heart of Batman Begins very difficult to swallow: the bad guys lace the water supply with a toxin that induces psychosis, but assuming that Gotham City is basically New York City, they’d have to be dumping at least 500,000 gallons per day for 100 ppm toxin in the water supply — some 9100 55-gallon barrels. That’s quite a logistical headache to hide, deliver, and dispose of that many barrels. I won’t go into the details of pipe networks that also make this improbable — the work of fiction did get people to ask me questions about water supply, which is never a bad thing.
I have digressed. The NYC UV disinfection plant will be the second treatment step for New York’s water supply, besides chlorination. Given the reports from Wisconsin about the necessity for UV disinfection to prevent viral gastroenteritis, New Yorkers could soon be a lot healthier. Turns out the EPA has been quietly requiring a secondary step for water treatment on top of chlorination, whether it be filtration or UV disinfection. EPA has been worried about standard water-borne pathogens like Giardia, Cryptosporidium, and Adenovirus, but this rule has preempted the latest research on the role of viruses in water-borne illness. Good job, EPA!