Monday, January 29, 2007

Broadwater's Hot Water

Broadwater’s liquefied natural gas terminal would take in millions of gallons of water from Long Island Sound, use it as a coolant, and then discharge the water back into the Sound at a higher temperature – an average of 3.6 degrees Fahrenheit warmer. This is called thermal pollution, and the scientists and government experts who have reviewed the Broadwater environmental impact statement think it is potentially a problem. They also think that the impact statement did a poor job analyzing it. Sam Wells, who comments frequently here and who used to live on the Sound in Connecticut, sent me some further thoughts:

Duck Island, circa1972

Duck Island is a very small island off Westbrook, Connecticut, which was probably in view of famous folks like Katharine Hepburn’s house on the shore. We didn’t know that back then, as they were secretive over there, not like us commoners in Clinton. So once every year, a bunch of us Clintonites would sail or motor over there to “take over” Duck Island, right in front of their famous yacht club. Seriously, we planted a flag, had a barbeque, honked our horns, and it was a blast. It wasn’t more than a shelly sand spit of maybe 5 acres.

But that summer there was an unusual outbreak of red jellyfish, the Lion’s Mane, known for its intense sting similar to that of a Portuguese Man-O-War. My little brother got stung by one across the chest and nearly drowned, right next to about 50 other boaters and swimmers on good old Duck Island. He screamed, went under, and we had to fish him out.

Being a kid, I listened to the men-folk ponder the massive infestation of the red jellyfish, talking in low, serious voices: “maybe Millstone … nuclear power plant … cooling water.” True enough, Millstone Unit One down by New London had just opened up a few years earlier in 1970, and the watermen noticed a different mix of fish, especially trash fish, and now an invasion of the Lion’s Mane. The power plant used ocean cooling water and could have been warming up the Sound on the incoming tide.

In subsequent years I found that the connection between the Lion’s Mane and Millstone’s cooling water might not have been exactly true, since the Lion’s Mane thrives in colder waters but will end up in the shallow bays and inlets in the summertime. Within a few years the infestation simply disappeared. However, because of warmer water temperatures the ecology of that part of the Sound shifted tremendously and fundamentally, at least in our minds on that hot, becalmed day on Duck Island.

It turns out that thermal pollution is a big issue for Long Island Sound, even if the tipping point didn’t occur in 1972. Warmer peak summertime water temperatures allow for more rapid blooms of certain kinds of algae, given the increasing nutrient loads. Bacteria decompose the dead algae and consume the available oxygen. Thermal pollution continues to be a relevant issue even today, with large industrial projects being proposed such as Broadwater.



Anonymous Rick said...


The lion's mane jellyfish (Cyanea capillata) has a multi-stage life cycle. It begins as a planktonic larva, but then it settles on the undersides of hard objects (it is negatively phototaxic, or light avoiding) and becomes a polyps. As a polyps, its tentacles segment and break off (budding) and the buds become the medusae, or jellyfish with which we're familiar.

Now, here's the interesting part. Researchers have discovered that the budding process stops when water temperature rises to approximately 57 degrees F. In other words, when bottom water temperature (where most polyps are found) reaches 57 degrees later in the season, the budding period is longer. Hence, in those situations, we'd expect to see more lion's manes during mid-late summer.

9:37 PM  
Blogger Sam said...

Hey thanks, Rick!

All I know was that a bunch of us started chopping them up with our outboard motorboat props, until my dad said that the Lion's Mane could form hundreds of new jellyfish that way. The word was passed down the waterfront and we stopped doing that.

Fascinating second part there ... could you elaborate?

11:09 PM  
Anonymous Rick said...


So you're the miserable cuss who caused those lion's mane blooms with your outboard engine!!! Seriously, the lion's mane (and all other jellyfish) have stinging cells (called nematocysts) that are capable (and will) activate even if detached from the medusa. That's because the jellyfish has a nervous system, but no brain (not at all unlike some drivers I've encountered on I-95) so its reflexes act independently.

Incidentally, the lion's mane is the subject of one of Doyle's Sherlock Holmes short stories, "Adventures of the Lion's Mane." In the story, the jellyfish killed someone, but it's somewhat open-ended as to whether or not the suspect in the case used it as a weapon. However, unless one has an allergic reaction, it's doubtful that the sting of the lion's man could be anything more than very irritating (again, like those drivers on I-95). But I digress...

I will tell you that Winter of '77-78 was very cold, and Summer of '78 was a bad one for lion's manes (or a good one for lion's manes, and a bad one for swimmers).


5:46 PM  

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