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006-Sound Bites

I’ve found life a bit more complicated than sound bites.  In the cost estimating community people used to say "In God we trust, all others provide data."  I never liked the phrase because it had a sense of cynicism and disrespect.  But there is some truth with it and I like the trusting God part.  Although sound bites sound good, they tend to obfuscate the real world.

The cruising guide, written by "the expert on the Great Loop" says you have to time your transit of the Delaware Bay with the tides.  He then goes on about how awful it could be if you don't.  The Great Loop blogg is full of people extolling the need to do your homework and time your passage with the tides.  One guy did a bit of rant against those who didn't know the difference between tides and currents.  Someone else, claimed to be the Delaware Bay expert, said you should embark 2hrs before slack water of the tide you want to ride.  But none of this talk seems to fit the facts.
The transit is about 70 miles.  Our boat travels at about 7mph (excuse the lack of nautical).  Without current we need about 10 hrs to do the trip.  Tides transition in the Mid-Atlantic region approximately every 60hr 20min intervals and they do so progressively.  Downstream starts the transition and slowly reverses the flow as it spreads upstream.  Upstream could be in a flood state while downstream is in an ebb.  This makes it all very complicated if not impossible to time "riding the tide.”  Sure you can start out riding the tide but it will likely transition at some point and you'll be fighting it.
Wind, in my mind, is the bigger issue since the tides we saw were only about 2kts max, not the docktale 5kts we’d been told.  It generates the waves, which if it opposes the current will generate bigger waves.  And on the Delaware which is very shallow, those waves will be a short frequency with a high amplitude that could bring any boat to a stop.  I think this is what people mean when talking about "timing the tide".  There is something to this sound bite but you really need to look at the wind predictions in addition to the tides to get a more complete picture.

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