Mapping with the Public Land Survey

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Mapping with the Public Land Survey

• Understanding Township and Range Notation

Original Author Stan Celestian Maricopa County
Comm. College District
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DETERMINING POSITION ON THE MAP TWO BASIC
TECHNIQUES
The Public Land Survey (PLS)
The Public Land Survey system is a grid system
based on points of reference across the United
States. All reference sites are located with
reference to a BASELINE which is an east west
line and a MERIDIAN which is a north south
line. ()
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The Public Land Survey (PLS)
From this point an east west line is drawn.
This is the BASELINE.
BASELINE
This dot represents a spot of geographic
prominence in an area. It could be a hilltop,
the confluence of two rivers or any easily
recognizable and easily accessible point. ()
Next a north south line is drawn. This is the
MERIDIAN.
MERIDIAN
The next step in the survey is to accurately
establish more north south and east west
lines at 6 mile intervals. ()
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The Public Land Survey (PLS)
These vertical north south lines can also be
extended farther east or west by the survey team.
()
BASELINE
MERIDIAN
These east west lines can extend as far as
needed by the survey team. ()
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The Public Land Survey (PLS)
From this basic grid pattern a system of location
can be established. Where is the star located?
()
BASELINE
MERIDIAN
It is located on the second row south of the
BASELINE and on the fourth column to the west of
the MERIDIAN. ()
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The Public Land Survey (PLS)
This is basically how it is done, except that the
rows the horizontal squares are called
TOWNSHIPS and the vertical squares are called
RANGES. ()
BASELINE
Range 1 East
Range 2 East
Range 3 East
Range 4 East
Range 1 West
Range 2 West
Range 3 West
Range 4 West
The Townships are numbered in a similar manner.
()
MERIDIAN
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The Public Land Survey (PLS)
Township 4 North
Township 3 North
Township 2 North
BASELINE
Township 1 North
Township 1 South
Township 2 South
Township 3 South
MERIDIAN
Township 4 South
So the star is located in Township 2 South and
Range 4 West. T2S. R4W ()
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That star is in a square that is 6 miles on a
side. This is an area of 36 square miles. If
that star were your house and you told a friend
that it was located in Township 2 South (T2S) and
Range 4 West (R4W), your friend may have a hard
time finding your house. ()
So each of these 36 square mile areas (these are
called townships) is divided up into 36 squares.
Each square is 1 mile on a side or 1 square mile
in area. ()
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Each square of the township is called a SECTION.
There are 36 sections in a township. Note how
they are numbered - ()
Now you can narrow down the area of where the
star is located. It is located in Section 29 of
T2S and R4W. ()
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One square mile (a section) is a very large
amount of land. ()
To make it easier, the section is further
divided. It is divided into quarters.
The star is located in the top right quarter of
the section. In PLS terminology the star is in
the northeast quarter of section 29. Here are
the quarter designations. Remember that north is
always to the top. ()
NE 1/4
NW 1/4
29
SW 1/4
SE 1/4
So the star is located in the NE quarter of
Section 29, T2S, R4W. In most cases this may be
enough to locate an object on a topographic map.
But each of these quarter can be subdivided into
quarters. ()
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Each of the ¼ of a square mile can be further
divided into quarters. ()
The top right quarter becomes the NE ¼ of the NE
¼. Followed by the NW, SW and the SE ¼s.
NE
NW
SW
SE
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So the star is located in the NE ¼ of the NE 1/4
of Section 29, T2S, R4W. This will be the extent
of using the PLS system in the lab. But you can
see that even this little (¼ x ¼ 1/16 of a
square mile) NE ¼ can further be divided into
many more quarters to create a smaller area in
which the object is located. This is the method
of location commonly used by real estate as well
as many cities and municipalities. ()
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At this point in the activity, open ArcView 9.1
to answer related questions about Township and
Range in Noble County.