||The Public Land Survey System (PLSS)
is the PLSS?
||What is the PLSS?
||The Public Land Survey System (PLSS) is a way of subdividing and describing land in the United States. All lands in the public domain are subject to subdivision
by this rectangular system of surveys, which is regulated by the U.S.
Department of the Interior, Bureau
of Land Management (BLM).
National Atlas of the United States®
The PLSS is used to divide public domain lands, which are lands
owned by the Federal government for the benefit of the citizens
of the United States. The original public domain included the land
ceded to the Federal Government by the thirteen original States,
supplemented with acquisitions from native Indians and foreign powers.
It encompasses major portions of the land area of 30 southern and
western States. Since the original PLSS surveys were completed,
much of the land that was originally part of the public domain has
been transferred to private ownership and in some areas the PLSS
has been extended, following similar rules of division, into non-public
domain areas. PLSS rules of division are explained below. For areas
that were once part of the public domain, legal land descriptions
are usually written in terms of PLSS descriptions.
The PLSS typically divides land into 6-mile-square townships, which
is the level of information included in the National Atlas. Townships
are subdivided into 36 one-mile- square sections. Sections can be
further subdivided into quarter sections, quarter-quarter sections,
or irregular government lots. Normally, a permanent monument, or
marker, is placed at each section corner. Monuments are also placed
at quarter-section corners and at other important points, such as
the corners of government lots. Today permanent monuments are usually
inscribed tablets set on iron rods or in concrete. The original
PLSS surveys were often marked by wooden stakes or posts, marked
trees, pits, or piles of rock, or other less-permanent markers.
The PLSS actually consists of a series of separate surveys. Most
PLSS surveys begin at an initial point, and townships are surveyed
north, south, east, and west from that point. The north-south
line that runs through the initial point is a true meridian and
is called the Principal Meridian. There are 37 Principal Meridians,
each is named, and these names are used to distinguish the various
surveys. The east-west line that runs through the initial point
is called a base line. This line is perpendicular to the Principal
Source: Principal Meridians and Base Lines,
Bureau of Land Management
||Each township is identified
with a township and range designation. Township designations indicate
the location north or south of the baseline, and range designations
indicate the location east or west of the Principal Meridian. For
example, a township might be identified as Township 7 North, Range
2 West, which would mean that it was in the 7th tier of townships
north of a baseline, and in the 2nd column of townships west of
a principal meridian. A legal land description of a section includes
the State, Principal Meridian name, Township and Range designations
with directions, and the section number: Nebraska, Sixth Principal
Meridian T7N, R2W, sec5.
While the original PLSS surveys were supposed to conform to official
procedures, some errors were made due either to honest mistakes
or to fraudulent surveys. Existing surveys are considered authoritative,
and any new surveys must work from existing corners and surveys,
in spite of errors in the original surveys and variations from
the ideal. This sometimes results in sections that are far from
square, or that contain well over or under 640 acres.
The early surveys in Ohio and Indiana were done when the system
currently in use had not yet been fully developed. While these
surveys have townships that are 6 miles square, the numbering system
used and the types of starting points for the surveys are different
from those used elsewhere in the United States. These surveys are
also named, although the names are not based on Principal Meridians.
Further information on these irregular surveys can be found in
the references listed at the end of this article. In particular,
see the Background Information on the Public
Land Survey System.
Source: Principal Meridians and Base Lines,
Bureau of Land Management
||In Louisiana, parcels
of land known as arpent sections or French arpent land grants also
pre-date the PLSS, but are treated as PLSS sections. An arpent
is a French measurement of approximately 192 feet, and a square
arpent (also referred to as an arpent) is about 0.84 acres. French
arpent land divisions are long narrow parcels of land usually found
along the navigable streams of southern Louisiana, and also found
along major waterways in other areas. This system of land subdivision
was begun by French settlers in the 1700s, according to typical
French practice at the time and was continued by both the Spanish
and by the American government after the acquisition of the Louisiana
Purchase. A typical French arpent land division is 2 to 4 arpents
wide along the river by 40 to 60 arpents deep, while the Spanish
arpent land divisions tend to be 6 to 8 arpents wide by 40 arpents
deep. This method of land division provided each land-owner with
river frontage as well as land suitable for cultivation and habitation.
These areas are given numbers just like standard sections, although
the section numbers frequently exceed the normal upper limit of
French arpent land division influence
Source: U.S. Geological Survey
by Thomas Jefferson, the PLSS began shortly after the Revolutionary
War, when the Federal government became responsible for large areas
west of the thirteen original colonies. The government wished both
to distribute land to Revolutionary War soldiers in reward for their
service, as well as to sell land as a way of raising money for the
nation. Before this could happen, the land needed to be surveyed.
Ordinance of 1785 which provided for the systematic survey and
monumentation of public domain lands, and the Northwest
Ordinance of 1787 which established a rectangular survey system
designed to facilitate the transfer of Federal lands to private
citizens, were the beginning of the PLSS. Under Congressional mandate,
cadastral surveys (surveys of the boundaries of land parcels) of
public lands were undertaken to create parcels suitable for disposal
by the Government. The extension of the rectangular system of surveys
over the public domain has been in progress since 1785, and, where
it applies, the PLSS forms the basis for most land transfers and
ownership today. The Manual
of Instructions for the Survey of the Public Lands Of The United
States, 1973 documents current official procedures for PLSS
Certain lands were excluded from the public domain and were not
subject to survey and disposal. These lands include the beds of
navigable bodies of water, national installations such as military
reservations and national parks, and areas such as land grants that
had already passed to private ownership prior to subdivision by
the Government. France, Spain, and Mexico all conferred land grants
in territory they claimed; many of these grants were confirmed by
the U.S Government when the territory in which they were situated
was acquired by the United States, and the land was then excluded
from the public domain.
Over the past two centuries, almost 1.5 billion acres have been
surveyed into townships and sections. The BLM is the Federal Government's
official record keeper for over 200 years' worth of cadastral survey
records and plats. In addition, BLM is still completing numerous
new surveys each year, mostly in Alaska, as well as conducting resurveys
to restore obliterated or lost original survey corners.
||Commonly Used Terms
|| Aliquot part—The
standard subdivisions of a section, such as a half section, quarter
section, or quarter-quarter section.
Base line—A parallel of latitude, or approximately
a parallel of latitude, running through an arbitrary point chosen
as the starting point for all sectionalized land within a given
Cadastral—Having to do with the boundaries
of land parcels.
Government lot—A subpart of a section which
is not described as an aliquot part of the section, but which is
designated by number, for example, Lot 3. A lot may be regular or
irregular in shape, and its acreage may vary from that of regular
aliquot parts. These lots frequently border water areas excluded
from the PLSS.
Initial point—The starting point for a survey.
Land Grant—A land grant is an area of land
to which title was conferred by a predecessor government and confirmed
by the U.S Government after the territory in which it is situated
was acquired by the United States. These lands were never part of
the original public domain and were not subject to subdivision by
Principal meridian—A meridian line running
through an arbitrary point chosen as a starting point for all sectionalized
land within a given area.
Public domain—Land owned by the Federal
government for the benefit of the citizens. The original public
domain included the lands that were turned over to the Federal Government
by the Colonial States and the areas acquired later from the native
Indians or foreign powers. Sometimes used interchangeably with Public
Public lands—Lands in public ownership, therefore
owned by the Federal government. Sometimes used interchangeably
with Public domain.
Range—A vertical column of townships in the
Section—A one-square-mile block of land,
containing 640 acres, or approximately one thirty-sixth of a township.
Due to the curvature of the Earth, sections may occasionally be
slightly smaller than one square mile.
Township—An approximately 6-mile square area
of land, containing 36 sections. Also, a horizontal row of townships
in the PLSS.
Cadastral Survey History
Federal Land Records
PLSS CadNSDI Data Set Availability
PLSS Standards, Standards for Digital Line Graphs, Part 3: Attribute Coding Appendix 3.11.A - Background Information on the Public Land Survey System