The North Carolina Department of Environment and Natural Resources, Division of Water Quality, in cooperation with the NC Center for Geographic Information and Analysis, developed the digital Water Supply Watersheds data to enhance planning, siting and impact analysis in areas directly affecting water supply intakes. This file outlines the extent of protected and critical areas and stream classifications for areas around water supply watersheds in which development directly affects a water supply intake. This file enables users to identify the areas which have special restrictions for building and development based on water supply intakes. This file is updated as changes occur.
This data was created to assist governmental agencies and others in making resource management decisions through use of a Geographic Information System (GIS).
Revisions and updates to this layer include: 38.) The July 01, 2007 update: A) Water Supply Boundary modified for Mills River WS-III to include all streams in the watershed per rule definition 37.) The March 01, 2007 update: A) Watersheds added for the Towns of Forest City and Shelby 36.) The October 12, 2006 update: A) Critical Area Boundary added for Town of Elkin water intake B) Watersupply Watershed Boundary removed for He Creek, Jerry Branch, and Henry Fork areas due to reclassification to WS-V 35.) The January 31, 2005 update: A) Critical Area Boundary corrected for the Rocky River watershed. This affects the Crutchfield Crossroads 24k quad. 34.) The August 6, 2004 update: A) Addition of Neuse River (Wake Forest) watershed. This affects the Franklinton, Grissom, Rolesville, and Wake Forest 24k quads. B) Addition of Fantasy Lake (Rolesville) watershed. This affects the Rolesville 24k quad. 33.) The January 31, 2003 update: A) Addition of Killets Creek watershed. This affects the Carthage 24k quad. 32.) The August 2, 2002 update: A) Critical Area Boundary extended for the Hiwassee River (Murphy) watershed. This affects the Peachtree 24k quad. B) Addition of Neuse River (Lenoir County) watershed. This affects the Deep Run, La Grange, and Seven Springs 24k quads. 31.) The June 27, 2001 update: A) Critical Area Boundary corrected for the Hiwassee River (Murphy) watershed. This affects the Peachtree 24k quad. 30.) The April 11, 2001 update: A) The class for the Fuller Creek watershed changed from WS-II to WS-III. This affects the Yanceyville 24k quad. B) Boundary corrected between the Nicks Creek watershed and the Little River (Intake #2) watershed. This affects the Southern Pines 24k quad. 29.) The October 24, 2000 update: A) Correction made to the critical area for the Country Line Creek watershed. This affects the Anderson, Cherry Grove, Park Spring, and Yanceyville 24k quads. 28.) The August 7, 2000 update: A) Correction made to the critical area for the Mayo River watershed. This update affects the Mayodan 24k quad. 27.) The June 14, 2000 update: A) Correction made to the critical area for the Lake Norman watershed. This update affects the Lake Norman North 24k quad. B) 'Donut hole' polygon removed that should have been deleted when the protected area boundary for Catawba River (Morganton) watershed was modified. This update affects the Oak Hill 24k quad.
Data creation and revision dates
Acknowledgement of products derived from this data set should cite the following: The source of the Water Supply Watersheds data is NCOneMap. Earlier versions of this dataset may exist. The user must be sure to use the appropriate data set for the time period of interest. While efforts have been made to ensure that these data are accurate and reliable within the state of the art, CGIA cannot assume liability for any damages or misrepresentation caused by any inaccuracies in the data or as a result of changes to the data caused by system transfers.
512 N. Salisbury Street
Preferred contact is by email or telephone.
NC Dept. of Environment and Natural Resources; Div. of Water Quality Director; Planning Section; Classifications and Standards Unit Supervisor NC Dept. of Environement and Natural Resources; Center for Geographic Information and Analysis
The NC DENR-Division of Water Quality delineated the boundaries on 24k USGS paper topographic maps. NCCGIA digitized these boundaries and attributed them with DWQ classification information, river basin and stream names, and acres per polygon. The digital files were plotted and overlayed to the originals and linework and label corrections were made. This digital file is updated as changes occur.
Using ESRI's ARC/INFO GIS software, the dataset was built for arc and polygon topology using the "build" command. The data set was then cleaned with a fuzzy tolerance of 1 foot. Topology has not been edited since the last build or clean.
These data represent the locations and identities of Water Supply Watersheds in North Carolina as mapped by the NCDWQ. Each watershed is labeled with either a protected or critical area classification. All boundaries are approved by DWQ whether they are the original DWQ boundaries or changes to original boundaries submitted for revision by local or county governments.
Water supply watershed boundaries were marked on 7.5 Minute USGS paper topographic maps which meet National Map Accuracy Standards, using a best estimate with reference to surrounding features. Ridge lines were interpolated from contours by cartographers and reviewed by DWQ staff. Counties and municipalities have restudied certain boundaries in detail for adjustment by DWQ. Boundaries drawn were digitized and check plots used to ensure correct boundary location, within a line width. map units: meters, precision: single, fuzzy: 1.0, dangle: 0.2
Water supply watershed boundaries and stream classification schedules
Paper maps used to delineate the watersheds
Digitization of the boundaries, and file updates.
Water supply watershed boundaries were delineated by cartographers interpolating ridgelines on paper USGS 7.5 minute topographic maps. Boundaries were delineated around known water supply intakes. Intakes on streams or rivers had critical areas delineated as ridgelines or half mile buffers, whichever was closest, upstream of the intake location. Protected areas were delineated with ridgelines or ten mile buffers, which ever was closer. For intakes on lakes and reservoirs, buffers were delineated from the apparent pool elevation of the water body as shown on the USGS quadrangle using the same limits as above. Boundaries were reviewed by DWQ staff. After the linework was digitized by NCCGIA (see below), DWQ staff reviewed the linework and attributes for accuracy. DWQ supplies CGIA with updates as they occur.
512 N. Salisbury Street
Phone or electronic mail
Internal feature number.
ESRI
Feature geometry.
ESRI
Total perimeter in coverage units
Software computed
DWQ stream classification for watershed
NC DENR-Div of Water Quality (Water Quality Planning Section)
Critical Area
NC DENR-Div of Water Quality (Water Quality Planning Section)
Nutrient Sensitive Waters which require limitations on nutrient inputs
NC DENR-Div of Water Quality (Water Quality Planning Section)
Outstanding Resource Waters which are unique and special waters of exceptional state or national recreational or ecological significance which require special protection to maintain existing uses.
NC DENR-Div of Water Quality (Water Quality Planning Section)
Waters protected as water supplies which are in natural and undeveloped watersheds
NC DENR-Div of Water Quality (Water Quality Planning Section)
Waters protected as water supplies which are generally in predominantly undeveloped watersheds
NC DENR-Div of Water Quality (Water Quality Planning Section)
Waters protected as water supplies which are generally in low to moderately developed watersheds
NC DENR-Div of Water Quality (Water Quality Planning Section)
Waters protected as water supplies which are generally in moderately to highly developed watersheds
NC DENR-Div of Water Quality (Water Quality Planning Section)
Acres per polygon (this is recalculated after the file is changed)
Software computed
Area of feature in internal units squared.
ESRI
A polygon dataset depicting areas classified by the Division of Environmental Management as having either protected or critical water supply watershed areas.
Refer to source agency for published stream classification documents.
301 N. Wilmington Street, Suite 700
20322 Mail Service Center
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NCCGIA is charged with the development and maintenance of NC OneMap and, in cooperation with other mapping organizations, is committed to offering its users accurate, useful, and current information. Although every effort has been made to ensure the accuracy of information, errors and conditions originating from physical sources used to develop this dataset may be reflected in the data supplied. The user must be aware of possible conditions and bear responsibility for the appropriate use of the information with respect to possible errors, original map scale, collection methodology, currency of data, and other conditions specific to certain data. NCCGIA does not support secondary distribution of this dataset without its current, compliant metadata record. The use of trade names or commercial products does not constitute their endorsement by NCCGIA or North Carolina State Government.
Data can be customized on a cost-recovery basis. Contact dataq@ncmail.net or 919-733-2090 for more information.
301 N. Wilmington Street, Suite 700
20322 Mail Service Center
Phone and electronic mail preferred