S.C. Code Regs. 117-1740.2 — Cadastral Maps and Parcel Identifiers

Section 1: Scope
This regulation provides requirements for the development and maintenance of cadastral maps and
parcel identifiers which will be used by the Assessors to locate, inventory and appraise all real property
within their jurisdiction. A county may elect to develop and maintain a manual mapping system or a
digital (automated) mapping system; however, each county shall have a system of maps that conform
to the minimum standards contained herein.
Section 2: Definitions
A. Base maps locate the major physical features of the landscape and contain the fundamental
information from which the cadastral maps are prepared. Base maps should be tied to the geodetic
network, either by means of ground control surveys or satellite methods of surveying. Base maps
provide the means to relate the locations of cadastral parcels to the geodetic reference framework.
Base maps can be in the form of line maps (generated manually or by computer) or photographic
maps. Regardless of the form, base maps are usually created from aerial photographs. Aerial
photographs provide an efficient and economical means for preparing the base maps.
B. Cadastral maps, also known as tax maps, should be viewed as overlays to the base maps. There
should be cadastral maps for the entire assessing jurisdiction, showing ownership, the size and position
of each parcel in relation to other properties, bodies of water, roads, and other major geographic
features. The maps should be produced at an appropriate scale and display all boundary lines,
dimensions, or areas; identifying parcel numbers; and other pertinent legal and descriptive informa-
tion. The maps provide a physical framework upon which non-physical parcel information can be
displayed, such as assessment comparisons, land appraisals, and market or other statistical data.
C. A parcel of land, for the purposes of this regulation, is a contiguous area of land under one
ownership. The parcel is the area of land that, as determined by the Assessor, should be included in
the description for appraisal and assessment purposes after considering all legal and practical factors.
Parcels may have been conveyed by one or more legal instruments, or created by survey, and may
contain several lots or fractions of a lot. Each parcel represents one property record, which is one unit
of land that is capable of being separately assessed.
Section 3: Map Content
Each county shall have a system of maps that conform to the following minimum standards:
1. Aerial photography must cover the entire county. This photography may be stored on
reproducible hard-copy material or may be stored as digital or scanner computer files. In either case,
the county shall maintain the ability to provide hard-copy reproductions of the photography. New
photography must match the existing photography within three percent (3%) of the width and length
and contain all of the neat area.
Reflights of aerial photography for the entire county must be made every ten years. Counties may
delay reflights for a period of up to two years with written permission from the Director of the
Department of Revenue or his or her delegate. An example of a reason for requesting a delay of a
reflight would be a county had experienced little or no change.
Each photograph will be individually rectified to best fit a minimum of three (3) identifiable points
each of which will be spaced at least 5 9 apart at the mean elevation of the terrain on the negative scale
of photography. As related to these points, there shall be no more than a three percent (3%) scale
error between each point taken from available existing maps, such as large scale base maps or existing
cadastral maps.
The flights will be made during snow free months when foliage is off the deciduous trees. The
photography will be made during the hours of 9:30 A.M. to 3:00 P.M. Eastern Standard Time and
when the altitude of the sun is at least 30 degrees above the horizon.
In addition, there shall be at least a three (3) inch overlap for rectified photo enlargements, and at
least a 1.5 inch overlap for orthophoto enlargement. The camera used shall meet the U. S. Geological
Survey specifications.
2. Scale of Photography
A. Counties acquiring aerial photography shall utilize the following scales:
1. Property outside incorporated city limits or subdivisions - 1 9 = 4008
2. Property within incorporated city limits and subdivisions - 1 9 = 1008 or 19 = 508
B. Deviation from scales set forth herein may be modified only with written permission of the
Director of the department or his or her delegate. Before approving a deviation from the scale, the
county must provide the department with a recommendation from the South Carolina Office of
Research and Statistical Services of the Budget and Control Board that the scale proposed to be
adopted by the county is sufficient to provide the information required by this regulation and is
appropriate to use in preparing the map.
3. Cadastral Map Preparation. Cadastral maps shall be prepared using aerial photography
(Section 3, part 1) as the base map. Other available sources deemed reliable by the Assessor may be
used to compile the cadastral map such as deeds, plats, field research and existing maps as well as
county, state and federal statutes identifying boundaries. Each cadastral map shall be compiled at the
same scale as the corresponding aerial photographic base map, shall be oriented north, and shall show
the following:
A. Boundaries of each property, lot or parcel identified by the Assessor.
B. Dimensions of each property, lot or parcel identified by the Assessor to the nearest foot where
possible.
C. Assessor's assigned parcel identifier.
D. Streets, railroads, rights-of-way, rivers, lakes, and streams (and their names).
E. Acreage of the property, lot, or parcel rounded to the nearest tenth of an acre (for parcels five
acres and larger).
F. Names of Subdivisions.
G. Scale of the map.
H. Adjoining map references and/or match lines.
I. Tax Districts.
J. Municipalities
K. County Name.
L. NORTH Arrow.
M. Disclaimer note indicating that this is not a survey.
4. Cadastral Map Maintenance. Cadastral maps shall be continually maintained by qualified
personnel. As rural areas develop, 1 9 = 400 8 maps should be converted to 1 9 = 100 8 maps. Parcels
may be mapped at 19 = 1008 scale in areas where no 1 9 = 1008 photography exists.
5. Any county obtaining new photography or reflights of existing photography shall consider
recommendations of the South Carolina Office of Research and Statistical Services of the Budget and
Control Board.
6. Each county shall have the ability to reproduce the aerial photographs and cadastral maps.
Section 4: General Requirements.
1. Maps and /or digital map data shall be numbered and filed in such a manner as to be readily
retrievable for review, maintenance and/or reproduction.
2. Ownership records must be created, maintained and cross-referenced alphabetically by owner
name, and numerical parcel identifier.
3. All maps shall be maintained in a timely manner to reflect all legal and physical changes.
4. There shall be indexes for maps of all scales indicating the map number, the area covered by
the map, and location of the map.
5. If a county elects to establish a coordinate based mapping system, the maps and mapping
procedures must meet the requirements contained in the publication ''Standards and Procedures for
County Base Mapping,'' published by the South Carolina Office of Research and Statistical Service of
the Budget and Control Board.
Section 5: Numbering System.
1. Each county in the state shall have a standardized parcel numbering system. If a county utilizes
a manual mapping system, a sequential parcel numbering system shall be used that shall conform to
the following minimum standards:
A. Each parcel shall be identified by a minimum of a ten (10) digit number which shall include:
Map Number - 3 digits
Sub-map Number - 2 digits
Block Number - 2 digits; and
Parcel (lot) Number - 3 digits
B. Each character within the identification number shall be numeric - no alpha (letter) characters
shall be permitted.
C. Additional characters and/or decimals may be added to each field of digits, however, all
additional characters shall be numeric. No alpha (letter) characters shall be permitted.
D. All characters within the numbering system shall be used to identify ownership parcels relative
to map, sub-map, block and parcel number. No references to political subdivisions (school districts,
municipalities, etc.) shall be included within the numbering system.
2. If a county utilizes a digital mapping system which is referenced to the S. C. State Plane
Coordinate (SPC) System: that meets or exceeds National Standards of Map Accuracy as determined
by the South Carolina Office of Research and Statistical Services of the Budget and Control Board, a
coordinate-based parcel numbering system may be used in lieu of or in conjunction with a sequential
parcel numbering system. The coordinate-based system must meet the following minimum require-
ments:
A. The visual center (centroid) of each parcel shall be assigned a coordinate value based upon its
location within the S. C. SPC. This coordinate shall consist of a fourteen (14) digit number
representing the Easting (7 digits) in feet and the Northing (7 digits) in feet. For example,
coordinates for the visual center of a parcel as measured from the cadastral map:
''X'' coordinate (Easting) - E 2,715,569
''Y'' coordinate (Northing) - N 0,756,737
B. The digits in each coordinate value are paired by taking each digit separately from the east-
coordinate and matching it with the corresponding digit of the north coordinate.
20 77 15 56 57 63 97
EN EN EN EN EN EN EN (E-Easting, N-Northing)
C. With this arrangement, the above example of a parcel identifier may be sorted as follows:
20 - Redundant lead number
7715 - number of basic map module at scale of (1 9 - 4008)
56 - Block number
5763 - Lot or parcel number
97 - utilized only to extend the capacity of the system
D. The parcel Identifier is obtained by recording the middle three sets of numbers (ten digits),
and is written with dashes as follows:
7715-56-5763
E. Records of condominiums, townhouses or other cases of diverse ownership on one parcel of
land will be further identified by the use of a decimal at the end of the parcel identifier with three (3)
digits to the right of the decimal. The records for a condominium unit or units built on the above
described hypothetical parcel could be assigned a suffix number to the parcel identifier of .001
through .999. For example, a condominium unit could have the following parcel identifier number.
7715-56-5763.008