A plat is a map, drawn to scale, showing how a piece of land is divided. Township plats were created by the U.S. General Land Office surveyors to show the distance and bearing between survey corners, and sometimes topographic or vegetation information. City, town or village plats are divided into lots with streets and alleys, usually for the purpose of selling the described lots; this is known as subdivision. After a plat is filed, legal descriptions can refer to lot numbers rather than portions of sections.

In order to be considered legally valid, plats must normally be reviewed and approved by a local governing body, such as a public works department, urban planning commission, or zoning board.

Types of Plats

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A Plat of Consolidation is used when a landowner takes several parcels of adjacent land over and consolidates them into a single parcel. In order to do this the landowner will usually need to make a survey of the parcels and submit the survey to the governing body which would have to approve the consolidation.

A Plat of Subdivision is used when a landowner, or municipality, divides land into smaller parcels. If a landowner owns an acre of land for instance and wants to divide it in three pieces, a surveyor would have to take precise measurements of the land that is to be divided and submit the survey to the governing body which would then have to approve it.

A Correction Plat or Amending Plat is used to make minor corrections to an existing plat, such as correcting a surveying mistake or a scrivener's error. Such plats can sometimes be used to relocate lot lines or other features, but such use is usually tightly restricted by law.

A Vacating Plat is used to legally void a prior plat or portion of a plat. Such plats are normally allowed only when none of the platted lots have been sold and no construction of buildings or public improvements has taken place.

Reasons for Platting

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• Creation of a road or other rights-of-way.

• Ensuring that all property has access to a public right-of-way. Without such access, a property owner may be unable to utilize his or her property without having to trespass to reach it. The platting process restricts the fraudulent practice of knowlingly selling lots with no access to public right-of-way.

• Creation or vacation of easements.

• Dedication of land for other public uses, such as parks or areas needed for flood protection.

• Ensuring compliance with zoning. Zoning regulations frequently contain restrictions that govern lot sizes and lot geometry. The platting process allows the governing authorities to ensure that all lots comply with these regulations.

• Ensuring compliance with a land use plan established to control the development of a city.

• Ensuring that all property has access to public utilities.

History

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The creation of a plat map is also an important step in the process of incorporating a town or city according to United States law. Because the process of incorporation must be done at a courthouse, the incorporation papers for many American cities may be stored hundreds of miles away in another state.

For example, the original plat for the city of San Francisco, California, filed in 1849, is kept at the Clackamas County courthouse in Oregon City, Oregon, then the capital of the Oregon Territory and the site of closest federal land office. This is because California did not become part of the United States until 1850.

See also

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• Lot and Block survey system
• plat of Zion

Real estate | Surveying