[Talk-us] NHD data import question

[Alan Millar]

>I've been checking some of the imported data and my general feel is that it is 
>overdigitized.  I don't know if medium versus high reflects just the quality or 
>the amount of digitization.  That would be something to check.  One could also 
>just run some sort of simplification algorithm on all the data.


I definitely found this to be the case for some parts of the 
area I did (Washington County, Oregon).  


I particularly remember it on 
areas like ponds and lakes; not so much on rivers and streams.  Most of them were reasonable, but a fair 
number of them had way too many nodes.  


I used the JOSM "simplify way" quite a bit, which worked perfectly in my opinion.

It may be analogous to TIGER, in that NHD may have a composite dataset that got created in multiple ways.  It may show up more in some places than others.


- Alan