PLSS Data
The Public Land Survey System uses Townships and Sections, and encompasses almost 1.5 billion acres of land beginning
with the Land Ordinance of 1785. These surveys of townships and
sections begin in Ohio and extend to all parts of the United
States except the original thirteen colonies. There are
approximately 2.6 million section corners, each located about a
mile apart. PLSS assumes a flat earth, and earth curvature plus surveying errors
leads to some very interesting "rectangles".

US Data used to be downloaded from the BLM. This has apparently been
deprecated, and you have to deal with the wonderful ESRI Geodatabase format.
It is now up to you to convert those to shapefiles, in the same format they used
to have. Maybe it is time to just use Lat/Lont, UTM, and MGRS.
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Current
-
https://navigator.blm.gov/services. This is not very easy to
use, and we have not gotten it to work. You will probably have to
deal with the Geodatabase format; it might be possible to convert to
shapefile with QGIS.
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Old:
-
BLM download, in
zipped shapefiles. You can get state or county downloads. This will use a
popup, so insure that your browser will allow it (Internet Explorer may work
best). Do not get the Geodatabase format.
- Download
to a subdirectory under "c:\mapdata\plss"
directory, and unzip.
Because each set of files has the same names, you
must uncompress each download to a different subdirectory. The
shapefile "twnshp"
describes the township boundaries; "first"
has the section boundaries; and "ladesc"
describes quarter-quarter sections. You need the DBF, SHP, and SHX file
for each
shapefile. Since the BLM
may limit the size of downloads, you might have to merge
shapefiles on the merge menu of the
data manipulation form, or just
use multiple directories.
- Set the base directory to use on PLSS options. Make sure that the folder you want,
under "c:\mapdata\plss",
opens when you click on it, and then pick OK.
- The program can deal with the BLM files, and the alternates, but
they must be placed in different directories.
- You must use files downloaded after May 2004 in WGS84.
- The first time you use the files, the program will
rename the shapefiles to "twnshp_84" and "section_84" and
"quarter_84".
- You can remove some fields
from the files to save hard disk space.
- You can use the Calculate, PLSS position menu
choice. Double clicking on the map will show the position in
Lat/Long and PLSS.
Map Overlays PLSS
options. You can choose whether
to show townships, sections, and quarter
sections, and to label townships and sections.
- You can automatically draw the PLSS grid when a map draws. To do
this:
- Enable "Use PLSS" on Menu tab
of the options
form.
- Have "Auto Draw PLSS" check
box selected on the Vector Map tab of the
options form,
or on the grid options form.
- The grid will be drawn every time, with
the level of detail (townships, sections,
or 1/4 sections) depending on the scale
of the map.
The option to use Alberta township data has been
removed.
Online converters. Our experience is that the 1/4-1/4
database has problems, and you might want to verify any critical results (or
switch to more modern ways to locate positions, such as Lat/Long, UTM, or MGRS/USNG.
Web Services
Last revision 6/1/2020