24,000-scale NWI files were joined to create 1:100,000-scale
tiles which were then joined to created river basin
tiles. The tile names, abbreviations and approximate file
sizes are list here.
River Basin ABBREV MB
Broad brd 2
Cape Fear cpf 60
Catawba ctb 8
Chowan cho 8
French Broad frb 2
Hiwassee hiw 1
Little Tennessee ltn 1
Lumber lbr 24
Neuse neu 39
New new 2
Pasquotank pas 13
Roanoke roa 19
Savannah sav no digital data
Tar-Pamlico tar 31
Watauga wat 1
White Oak wok 10
Yadkin yad 19
Revisions and updates to this layer include:
system filename: /library/librb/tiles/(rivbasabbrev)/nwi
filesizes range from 1 - 60 mb per tile
4.) directory: nwi_599 filenames: (rivbas)nwi599
The May 1999 updates to this layer consisted of combining the
100k tiles into river basin files and stripping out the quadrangle
neatlines. During this update the data was also projected from NAD27
datum, State Plane projection, units of measure feet TO: NAD83 DATUM,
State Plane PROJECTION, UNITS OF MEASURE METERS. This was done to
comply with the NC Geographic Information Coordinating Council's
"Statement of Direction for North Carolina Corporate Geographic Database
Horizontal Reference, Datum and Unit of Measure". This reprojecting
was done in various ways depending on the data type and content.
Vector data was projected using the 'project' command in ESRI's Arc
software and topology was cleaned and built based on coverage needs.
Raster data was projected using ESRI's Grid module and various steps
as applicable.
3.) directory: nwi_1097 filenames: nwi(100kabbr)1097
In October 1997, additional 24k tiles were being combined into 100k
tiles. If the 24 k source changed at any time, these updates
were also added to the 100k. The following tiles were edited or
added: Asheville, Gastonia, Lancaster.
2.) directory: nwi_1995 filenames: nwi(100kabbr)(month)95
In 1995, additional 24k tiles were being combined into 100k
tiles. If the 24 k source changed at any time, these updates
were also added to the 100k.
During the year, 29 tiles were created or updated as follows:
October 1995 - Bayboro
September 1995 - Norfolk, Plymouth, Whiteville
August 1995 - Raleigh, Roanoke Rapids
July 1995 - Asheville, Charlotte, Florence, Fontana Lake,
Gaston, Hendersonville, Johnson City, Knoxville, Laurinburg
June 1995 - Morehead City
May 1995 - Boone, Cleveland, Kinston, Salisbury
April 1995 - Fayetteville, Henderson
March 1995 - Chapel Hill, Greensboro
February 1995 - Rocky Mount
January 1995 - Danville, Galax, Southern Pines, Wytheville
1.) directory: nwi_1994 filenames: nwi(100kabbr)(month)94
In 1994, the 24k tiles were being combined into 100k tiles.
If the 24 k source changed at any time, these updates were
also added to the 100k.
During the year, 14 tiles were created as follows:
November 1994 - Winston-Salem, New River, Manteo, Hickory
October 1994 - South Boston
September 1994 - Wilmington, Myrtle Beach, Elizabethtown
August 1994 - Virginia Beach, Cape Fear
June 1994 - Emporia, Elizabeth City, Currituck Sound
May 1994 - Cape Hatteras