On Mon, 18 Apr 2005 12:19:00 -0400, DSK wrote:

OK, here's a "Believe It Or Not" fact about the Hudson. The first lock
on the Hudson is at Troy, just below the Waterford Flight. Up until
that point, the river is tidal, even though it is 120 nautical miles
from NYC. What I didn't expect is that the tidal range at Troy (4.7
feet) is actually more than at NYC (4.4 feet at Chelsea Docks). Further,
the high water "wave" that crests in NYC takes 9 hours to reach Troy.
By the time it is high there, its already several hours past Low Water
in the city!


Water is heavy, and stubborn. It is surprising that the tide range at
Troy is more than at NYC though. Last week we heard Skipper Bob give a
very good talk on navigating the Hudson. He says to leave NYC at 3 hours
after low tide to get the best boost from tide... somewhat
counterintuitive...

It isn't really more than at NYC. Ft. Hamilton in NYC is also 4.7
feet. Other points between Troy and NYC are less. West Point, for
example, is 2.7 feet. Because it is very deep there, I guess the tidal
wave doesn't affect the surface as much, even though it is also rather
narrow.

I am not sure exactly where at West Point the reference is. The really
deep spot off Constitution Island is also the narrowest. In any case,
the currents are of more concern than the up and down in the river.


Rodney Myrvaagnes Opionated old geezer

Faith-based economics: It's deja voodoo all over again