## Where are you surveying?

### Measurements in Land Surveying

When reading legal land survey descriptions there are several things a land surveyor must keep in mind to conduct a proper survey. For example, the following legal description is for a 42- acre parcel āĀ T39N, R23W, Sec. 4, NW1/4 SE1/4.

First, one must understand that punctuation is crucial in reading legal land surveys.Ā  If a comma were included in between the āNW1/4ā and āSE1/4ā of this legal measurement/description then it would alter the reading to be for a 320 acre parcel.Ā  Second, all legal descriptions are read backwards.Ā  The legal land survey description is read from right to left, going from the smallest unit of measurement to the largest unit of measurement.Ā  Understanding these key points will enable you to conduct a more precise and accurate survey.

The Rectangular Survey System

Land surveying consists largely of determining the measurements of parcels of land.Ā  The Rectangular Survey System or the Public Land Survey System (PLSS) is the primary type of land survey measurement system that the majority of the United States has been surveyed by.Ā  It is a system that is setup on a grid in which the primary objective is to determine approximate values of square sections measuring 1 square mile each (1 square mile = 5,280 feet).Ā  The rectangular survey system is the most common system land surveyors use throughout their career to define accurate and precise measurements.

Ā

In order to apply the rectangular survey system you must first understand a couple terms.Ā  These includeĀ prime meridians,Ā baselines, and principal meridians.Ā Ā Prime MeridiansĀ are north-south lines (lines of longitude), at which longitude is defined to be 0Ā°.Ā  The Prime Meridian starts at the North Pole and extends south to the South Pole.Ā  BaselinesĀ are lines that extend east-west.Ā Ā Principal meridiansĀ are the true north-south lines that run through the initial point of the area that is being covered.

Ā

All measurement starts at an initial point.Ā  Initial points in land surveying are usually set by astronomical observation.Ā  Across the United States there are 37 points where a principal meridian and baseline intersect.Ā  From each of these initial points, a prime meridian extends north-south, and a baseline extends east-west.Ā  Along the north-south prime meridian, initial points are marked at 24 mile intervals.Ā  Baselines extend from east to west from these points as well.Ā  Along the east-west baselines, points are marked at 24 mile intervals as beginning from the north-south prime meridian.Ā  The parallel points created from these points are called standard corners.

For each standard corner a line runs true north.Ā  These lines are calledĀ guide meridians.Ā  Due to the Earthās curvature, guide meridians do not intersect through standard corners along the next standard parallel, 24 miles to the north.Ā  The intersections they cross are called closing corners.Ā  Each standard now contains a set of both standard and closing corners.

Ā

Ā

Each 24-mile tract is divided up into 16 townships.Ā Townships areĀ roughly 6 miles x 6 miles.Ā  Starting at the southeast corner of the 24-mile tract, corners are established six miles apart along theĀ east-west parallelĀ and theĀ north-south meridians.Ā From these corners, range lines run true north to the nextĀ parallel, and township linesĀ run west to the nextĀ prime meridian.Ā  With that said, eachĀ townshipĀ is now divided into 36 sections,Ā a piece of land roughly 1 square mile x 1 square mile, or approximately 640 acres.Ā  This process is also used in defining corners and running lines from the southeast corner of theĀ township.Ā  Each of the 36Ā sectionsĀ is then divided into 16Ā forties.Ā  TheseĀ fortiesĀ are further subdivided, and subdivided, and subdivided.

Survey Legend

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### Featured Land Surveying Articles

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### Surveying Articles and Presentations

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Differences between Forums, Blogs and Article posts

Forum Posts are great for asking questions which have a definate answer.  Forum posts are best for a quick exchange of information between Land Surveyors United members.   Please note that All Community Hubs have their own dedicated Forums so if your post is related to a specific hub, it is best to ask your question or share your tip inside the hub in which it belongs for targeted answers.  For example, if your question relates to Leica equipment, ask your question inside the Leica Hub forum for best results as all members inside that hub uses the equipment in question.  Likewise if your question pertains to a Location, you should consider making your post inside the appropriate hub.

Blog Postsdiffer from Forum posts because you can embed and upload different kinds of information.  Blog posts are best for presenting information and updates for feedback and sharing.  When posting a Blog Post, you can also publish a short excerpt at the bottom which is what most members will see before reading the blog post.  Blog posts are also great for posting new surveying projects and digests of links to multiple surveying topics or your own website.   Things that can be embedded into Blog Posts are videos, images, slideshows, powerpoints, spreadsheets, PDFs, documents and more.

Articles are similar to Blog Posts in all ways except one.  Articles allow for you to post an Author Block at the bottom with links to your contact info, website information, credentials, etc. Similar to Blog Posts, things that can be embedded into Blog Posts are videos, images, slideshows, powerpoints, spreadsheets, PDFs, documents and more.  Similar to both types above, Hub Owners can add article sections and features to any hub they control on the community.