Converting USFWS NWI DLG's to GRASS

gregg hadish gahadish at
Tue Dec 19 07:00:00 EST 1995

I am converting USFWS National Wetland Inventory data to GRASS;
this can be done using, or v.import which works fine, 
however the category information is based on the internal polygon
id, instead of the wetland category id. For example one 7.5' quad
NWI file may have over 300 individual polygons numbered sequentially
1,2,3..., however there may be only 25 distinct wetland categories
represented in the file. The files can be reclassed based on the 
25 categories in v.reclass - this can be cumbersome, but does work

The difficulty is in patching together multiple NWI files to create
county-wide NWI files.  Each 7.5' quad file has a different number 
of wetland types, each with its own numbering scheme.

Has anyone figured out a "simpler" way of importing these files so that 
there are unique category numbers for the wetland types.

Thank you.

Please respond directly to

gahadish at

Gregg Hadish
Golden Hills Resource Conservation & Development
Oakland, Iowa

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