On Sat, May 5, 2012 at 9:19 PM, Paul Norman <[email protected]> wrote: > I've been looking at the NHD data from the USGS site and have noticed a few > recent changes from how they were described on the wiki. > > 1. The viewer has changed. http://viewer.nationalmap.gov/viewer/nhd.html > will bring up a map you can use to download NHD data. This viewer does not > work in Chrome but does work in IE. Subregions are pre-staged downloads, the > others will take some time before you can download. > > Subregions can be directly downloaded from > ftp://nhdftp.usgs.gov/DataSets/Staged/SubRegions/PersonalGDB/HighResolution/ > > Most subregions are available as a new NHD 931v210 file but some are still > being generated. > > 2. NHD data is now available only as File Geodatabases (File GDBs, .gdb) and > Personal Geodatabases (Personal GDBs, .mdb). My understanding is the default > builds of QuantumGIS and GDAL on Windows can open Personal GDBs. > > On linux gdal can be compiled with drv_mdb or the pgeo driver can be used > for Personal GDBs, or the filegdb driver can be used for File GDBs. This is > moderately technical. > > 3. The NHD attributes changed with NHD v2.1. All the old mappings of NHD > FCodes to OSM tags are outdated. For rivers and streams nothing has changed > but others have. I haven't found a list of the 2012 changes. > > The two current FCode lists I am aware of are > http://nhd.usgs.gov/userGuide/Robohelpfiles/NHD_User_Guide/Feature_Catalog/H > ydrography_Dataset/Complete_FCode_List.htm and > http://nhd.usgs.gov/NHDv2.1_poster_3_23_2012.pdf > > If you are planning something where you will be checking each object's > tagging this will not affect you too much, although you may encounter more > objects you have to retag. > > If you are considering proposing any kind of NHD import where you don't > check each option I suggest you wait. > > I am working on a translation file but it takes a fair amount of time. There > are a *lot* of FCodes and I need to look at some of each in multiple areas > to see the appropriate tagging. Not all FCodes appear in all areas and what > seems appropriate in one area may not be for all areas.
Thank you for your work on this. NHD hasn't been high on my priority list but I might actually try to use some of it around here once you get things in a working state. Toby _______________________________________________ Talk-us mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk-us
