[Talk-us] Combining State/County Borders & Physical Features?

Nathan Edgars II neroute2 at gmail.com
Sat Oct 15 09:36:11 BST 2011


On 10/15/2011 1:16 AM, Jeffrey Ollie wrote:
> I noticed in the past few days that user Alexander Roalter has been
> converting administrative boundaries in the Midwest to relations
> (which I think is good) but in some cases he's combined state and
> county boundaries with physical features, especially rivers.  A prime
> example is the eastern border of Iowa and western border of Illinois
> now shares the same ways as the Mississippi River.  I personally feel
> that combining administrative borders with other features is not the
> right way to handle the borders - while the boundaries may originally
> have been defined by the river that won't always hold, see the history
> of Carter Lake, Iowa for an example.

I think I would agree with using rivers in this case, if my assumptions 
are correct. That is, if the river shifts slightly in the same channel, 
the boundary moves to follow the main flow line (or however it's 
defined), but if the river moves to a different channel, the boundary 
remains. Since any such major relocation will require more to be changed 
than a single way, the boundary is not in danger of being moved 
incorrectly by anyone who knows what they're doing.

Of course this is only true when the boundary is defined to be the 
center of the river, rather than a line near one bank (e.g. the Ohio River).



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