[Imports] A few questions about importing U.S. NHD data for Subbasin 01080105 import (White River in VT)

[probiscus]

Hi folks-

Thanks for the excellent feedback! Sounds like I have some more work to do,
particularly updating my tag mappings and figuring out the best way to
merge adjacent ways.

One more thing to note, my plan is to map all of the flowlines to
waterway=stream, then just manually change 7 rivers that have areas to
waterway=river before importing. This matches my local knowledge and I
think this covers this area pretty well, as it is a hilly area, with few
manmade water features. While there are some features that should ideally
be ditch or canal here and there, the source data has no indication of
this, so that will just need to be corrected from aerials or by local
mappers (me).

>> You don't need to understand what every tag means, particularly
>> these data carried from import sources.
> This approach makes OSM uneditable. Imagine you don't know what the
> tag abcd=1234 means. What is a user supposed to do with that tag when....

While I do understand what every tag means, I think I can see the reason
behind both sides here. Note again that ComId is one of two ID'ing fields
in the NHD data, the other being ReachCode, which I will most definitely
import. I know importing these IDs might accomodate some "future
potential", but I guess the important questions are:

Do we have any examples of cases where imported source IDs have been used
to compare/update/modify either source or OSM data from the other? Has this
been done successfully using a tag like
"tiger:tlid=171531381:171531532:171531405:171531528" or possibly even
"tiger:tlid=woohoo"?

The features themselves are basically identifying data, what is the added
value of not just the one source id im planning to import but two source
ids?

What IS the user supposed to do with tags like tiger:tlid when splitting or
merging a way?

> using some sort of pseudo-ComID for these pre-combined ways.
Any suggestions as to how this might work? Are you just suggesting
"NHD:ComID=combined" for those ways which have been merged? Isn't this just
tiger:tlids with multiple values in disguise?

> Still, it allows other people to check out the results in potlatch / JOSM
very easily.

Sounds like once I have my import ready (but before official import), I
should run it on a test server and post to this list again for potential
review on that server

Anyway Thanks Again!

Scott
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