Hurricane Irene polluted Catskills watershed

September 26, 2012, Yale University
Samples taken from a stream in Esopus Creek in the Catskills during Hurricane Irene show the amount of sediment and organic matter collected during at 3.5-hour intervals. Credit: Bryan Yoon

(—The water quality of lakes and coastal systems will be altered if hurricanes intensify in a warming world, according to a Yale study in Geophysical Research Letters.

Bryan Yoon, the study's co-author and a doctoral student at the Yale School of Forestry & Environmental Studies, found that last summer during Hurricane Irene—the worst storm in the New York area in 200 years—record amounts of dissolved organic matter darkened Catskill waters and affected the Ashokan Reservoir that supplies New York City with drinking .

"This is the biggest rain event ever sampled for the region," said Yoon, who conducted the study with Pete Raymond, professor of ecosystem ecology at Yale.

As a primary source of drinking water for New York City, the Catskill Mountains is designated as forest preserve, and roughly 62 percent of the watershed studied is protected by New York State. Over a two-day period in late August 2011, Irene dropped over 11 inches of rain—17 percent of the average annual rainfall—on Esopus Creek that feeds the Ashokan.

Yoon found that the volume of water discharged by the creek increased 330-fold, and the creek exported an unprecedented amount of dissolved organic matter to the Ashokan, equivalent to 43 percent of its average annual export. Yoon likened the increase in dissolved organic matter to a person being fed 40 percent of his annual food in a few days.

Although not discussed as often as other topics such as turbidity, dissolved organic matter plays a critical role in the aquatic environment and for the provision of clean drinking water. In moderate quantities, dissolved organic matter also provides food and nutrients for microbial communities.

In excessive amounts, however, dissolved organic matter could lead to numerous environmental problems, Yoon's study found. Dissolved organic matter binds with metal pollutants and transports them; interferes with ultraviolet processes that reduce pathogens in water; affects aquatic metabolism; and leads to the formation of carcinogenic disinfection byproducts, such as trihalomethanes during chlorination.

"All of those problems become more serious as larger quantities of dissolved organic matter are transported to lakes and coastal systems," he said. " Irene was a prime example that there is no limit to the amount of dissolved organic matter that can be exported by extreme rain events. Surprisingly, concentrations of dissolved organic matter didn't get diluted."

Raymond said that frequent hurricanes will flush more out of the ground and into lakes, reservoirs and coastal waters, potentially altering their biogeochemical cycles.

Explore further: Dissolved organic matter in the water column may influence coral health

More information: The study, "Dissolved Organic Matter Export from a Forested Watershed during Hurricane Irene," was funded by the Hixon Center for Urban Ecology at F&ES and can be viewed at

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2 / 5 (4) Sep 26, 2012
"will be altered if hurricanes intensify in a warming world"

They are not intensifying. Tornadoes are down too.

"the worst storm in the New York area in 200 years"


"September 21, 1938 — The New England Hurricane of 1938 (Also Called "The Long Island Express") makes landfall on Suffolk County (Long Island) as a category 3 hurricane on the Saffir-Simpson hurricane scale.[19] Wind gusts of 125 mph (200 km/h) and storm surge of 18 feet (5 m) washes across part of the island.[20] In New York 60 deaths and hundreds of injuries were attributed to the storm.[21] In addition, 2,600 boats and 8,900 houses are destroyed.[22] Throughout New England the hurricane killed over 682 people,[23] damaged or destroyed over 57,000 homes, and caused property losses estimated at $4.7 billion (2005 US dollars)."

1 / 5 (2) Sep 26, 2012
Irene was definitely not the worst hurricane in New England in the past 200 years. There are at least 2 hurricanes in the past 200 years in the region that were far worse, Not Parker listed one of them.

Anyone who cares to do the research can look for the other; I'll leave it a secret, since most of you will negative me anyway, out of spite.

Besides, the hurricane didn't pollute anything.

the humans did the polluting.

the hurricane just washed away all the crap, natural and unnatural.
1 / 5 (2) Sep 27, 2012
How do you like your beachfront property now? Time to decide if you want to increase your insurance, or move to higher, dryer ground. Just ask yourself: how long can you tread water in hunded miles per hour storm conditions?
not rated yet Sep 27, 2012
it said largest rain event,not storm.what are the rain amounts for 38?
the idea that this flushed out the watershed is a good one,will the water for NY have better quality when this is over.
1 / 5 (2) Sep 27, 2012
it said largest rain event,not storm.what are the rain amounts for 38?
the idea that this flushed out the watershed is a good one,will the water for NY have better quality when this is over.

1955: Connie dropped more than 12 inches of rain at LaGuardia Airport

2011: Irene dropped up to 7 inches of rain across the city

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