In two months New Yorkers will pull from the world's largest ultraviolet water treatment plant, due to go online. The massive plant can process some nine billion liters of water daily, neutralizing any waterborne pathogens coming from the major sources serving the city — Delaware County and the Catskill watersheds.
Once operational, 56 massive UV units will kill any existing microorganisms left after initial chlorine treatment. The units are about 5.8 meters long, 1.7 meters wide and 2.3 meters tall; water will move through the unit at 1.5 meters per second and will be passing within centimeters of the unit's 240 UV lamps. The plant can use up to 6.3 megawatts of power on a high usage day.
The Catskill-Delaware plant located in Westchester County, built by Trojan Technologies, was built to meet 2006 EPA requirement that unfiltered surface water treatment systems like New York City's have two forms of treatment for waterborne microorganisms, toxins and yes — fecal matter from septic tanks upstate.
The city currently uses chlorine as a first measure of defense, which can work well for some bugs like the adenovirus, but some nasty organisms like the parasitic cryptosporidium and giardia aren't fazed by it. UV treatments alter the DNA of these microorganisms disarming what otherwise could have caused nausea, diarrhea and even more serious problems.
If all this sounds like overkill, that's exactly the point. The EPA wants to make absolutely sure what chlorine misses, another method of treatment addresses. New York City's other option would have been an expensive filtration system that passes the water through layers of porous materials such as sand, gravel and charcoal to grab up the toxins.
As anyone who has had a food or water borne illness can tell you, these microorganisms attack and devastate the body. When powered up the added protection of the New York plant should make everyone more confident as they open their taps.