TRS-data
State and Meridian
Township
Range
Section
Summary: This program returns the same information as Graphical Locater
for a valid legal description within 17 western states
(AR , AZ, CA, CO, ID, KS, MT, ND, NE, NM, NV, OK, OR, SD, UT, WA and WY).
The returned position is for the center of the section.
If you have questions on the conversion or need to run batch conversion jobs for many points,
see the trs2ll program
by Martin Wefald,
mwefald@hotmail.com.
Instructions: Select the State/Meridian and directions and input the Township,
Range, and Section numbers and then select submit.
If your state has more than one meridian and this is unknown, use the Graphical Locater
TRS2LL State Coverage Map
and select a position near your legal description.
The meridian is given with each legal description (line 2).
If the legal description is "unknown" to Graphical Locater, this program will not work either.
Note that some meridians are quite small.
The California BLM has a nice set of
maps showing the Principal Meridians and Base Lines and the areas they cover.
Here is section of one of these maps, used with their permision,
showing the states covered by this program.
Introduction:
The United States Public Land Survey (USPLS) started with the Land Ordinance of 1785 and
covers all US land that was not settled by the time of the official government survey.
It does not include the east coast states including Kentucky and Tennessee or Texas.
Small areas of other states that were settled before the survey also technically excluded.
This explains the odd shapes of many mining claims in the west.
Latter title transfers followed USPLS lines.
Legal descriptions to 1 mile square sections have 4 parts: the State/Meridian,
Township, Range and section number.
Note that an official legal description always works from small to large areas,
for example NW1/4, sec. 12, T.122N, R.71W, South Dakota, Fifth Principal Meridian.
- Meridian These are similar to UTM zones.
Both apply to large areas based on a line of longitude, both are often left out of field data,
and the position is not uniquely defined without them!
The position of the principal meridian for any area, in contrast to UTM zones,
is largely historical and arbitrary.
The area governed by each Meridian, also in contrast to UTM zones, is irregular in size and shape,
but it frequently follows state lines.
Actually it is more correct to say that the states were formed according to the areas covered by
the Meridians.
Some of these areas include several large states while others include only a small part of a single state.
Some of the smaller areas were caused by changes in tribal reservations.
The default principal meridian for this program (Principal) is good for (as you might guess) Montana.
- Township These occur at 6 mile intervals east and west of the principal meridian.
Township values are normally whole numbers starting at 1, but some exceptions occur.
Township lines are normally adjusted every 4th line to correct for the spherical nature of the earth.
These are called standard parallels.
- Range These occur at 6 mile intervals north and south of a base line that is associated with
each principal meridian.
The position of the base line for each principal meridian is also historical and arbitrary.
Range values are normally whole numbers starting at 1, but some exceptions occur.
Range lines are normally adjusted every 4th line to correct for the spherical nature of the earth.
These are called guide meridians.
- Sections
The intersection of Range lines and Township lines define 6 by 6 mile squares called Townships,
which are divided into 36 sections.
These are normally 1 by 1 mile squares, but some are altered to correct for the spherical earth.
Most of these departures are pushed to the northern and western tiers of sections
before the next standard parallels and guide meridians.
Others are altered by simple survey errors.
Note that old survey errors have legal precedence over new survey results so the odd-looking lines stay put.
Section numbers always range between 1 and 36.
Sections are normally divided by repeated quartering, but this is beyond the scope of this program.
The USPLS serves perfectly well for its intended used of land title management, but it is not very
suitable for scientific point location management.
Mapping and spatial statistics are much easier with a system that is more regular over large areas.
The conversion to latitude/longitude allows the USPLS data to be better used in many other systems.
The key conversion code is the trs2ll program
by Martin Wefald,
who has kindly made his program available for this project.
The Graphical Locater interface allows easy verification and fine tuning of the position data.
NOV 16 1999, updated on 17 JULY 2003, based on the trs2ll program received on 15 NOV 2001
Web interface and Graphical Locater by D.L. Gustafson,
dlg@rapid.msu.montana.edu
The trs2ll program
by Martin Wefald,
mwefald@hotmail.com.
gipoco.com
is neither affiliated with the authors of this page or responsible
for its contents. This is a safe-cache copy of the original web site.
gipoco.com
is neither affiliated with the authors of this page nor responsible
for its contents. This is a safe-cache copy of the original web site.