[Talk-us] U.S. inland waterways

[Dale Puch]

http://www.ndc.iwr.usace.army.mil//index.htm looks to be one of the places
you should look.
I found it thru
http://www.usace.army.mil/Missions/CivilWorks/Navigation.aspx in case there
is more information there.


On Wed, May 16, 2012 at 4:51 AM, Richard Fairhurst <richard at systemed.net>wrote:

> Nathan Edgars II wrote:
> > I'm trying to do something like the European tagging:
> > http://www.itoworld.com/map/24
> > But there they have some sort of international treaty that
> > defines configurations.
>
> (puts day-job hat on)
>
> For users of a waterway, the European (CEMT) waterway classes describe,
> rather than define, the size of the limiting structures. They're
> information, rather than regulation.
>
> In other words, although a class Va waterway has a stated length of 110
> metres, that doesn't mean that a river policeman will come and flag you
> down
> for taking a 115m boat along the river. It's very possible that the locks
> are (say) 120m long, and if you can get your boat through them, you're
> absolutely entitled to do so.
>
> This is particularly important at the smaller end of things where locks and
> bridges may be a zillion and one different sizes. (Here in Britain people
> routinely build boats to 60ft because there are certain locks that are 58ft
> 6in long... and if you put the boat in the lock diagonally, you can squeeze
> that little bit of extra accommodation. There are other locks that have
> subsided to become 1in too narrow for certain historic craft that would
> once
> have used the locks. And so on.)
>
> So the ideal is to tag each structure with its limiting dimensions, using
> the familiar maxwidth=/maxheight=/etc. tags. This is never going to be
> completely achieved, of course, because draught varies for each bit of the
> riverbed. ;)
>
> The next best thing is to tag the 'gauge' of a waterway - in other words,
> the largest dimensions that will fit through all the structures on that
> waterway. In Europe, tagging a waterway with the CEMT class would be a
> quick-and-dirty-though-not-particularly-accurate way of stating the gauge.
> (That said, the CEMT class would fit very well in the designation= tag.)
>
> cheers
> Richard
>
>
>
> --
> View this message in context:
> http://gis.19327.n5.nabble.com/U-S-inland-waterways-tp5709017p5709046.html
> Sent from the USA mailing list archive at Nabble.com.
>
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-- 
Dale Puch
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