Washington County, Colorado

Public Land Survey System (PLSS) United States of America

The PLSS is a way of subdividing and describing land in the United States. All lands in the public domain are subject to subdivision by this rectangular system of surveys, which is regulated by the U.S. Department of the Interior, Bureau of Land Management (BLM)

The original public domain included the land ceded to the Federal Government by the thirteen original States, supplemented with acquisitions from native Indians and foreign powers. It encompasses major portions of the land area of 30 southern and western States. Since the original PLSS surveys were completed, much of the land that was originally part of the public domain has been transferred to private ownership and in some areas the PLSS has been extended, following similar rules of division, into non-public domain areas.

The PLSS typically divides land into 6-mile-square townships, which is the level of information included in the National Atlas of the United StatesŪ. Townships are subdivided into 36 one-mile- square sections. Sections can be further subdivided into quarter sections, quarter-quarter sections, or irregular government lots. Normally, a permanent monument, or marker, is placed at each section corner. Monuments are also placed at quarter-section corners and at other important points, such as the corners of government lots. Today permanent monuments are usually inscribed tablets set on iron rods or in concrete. The original PLSS surveys were often marked by wooden stakes or posts, marked trees, pits, or piles of rock, or other less-permanent markers.

Most PLSS surveys begin at an initial point, and townships are surveyed north, south, east, and west from that point. The north-south line that runs through the initial point is a true meridian and is called the Principal Meridian. There are 37 Principal Meridians, each is named, and these names are used to distinguish the various surveys. The east-west line that runs through the initial point is called a base line. This line is perpendicular to the Principal Meridian.

Of interest to Coloradans is the Sixth principal meridian which determines the starting point for surveys in several western states. The 6th extends from the baseline coincident with the north boundary of Kansas in latitude 40°N south through the state to its south boundary in latitude 37°N and north through Nebraska to the Missouri River and governs the surveys in Kansas and Nebraska and Colorado except those projected from the New Mexico and Ute meridians the latter intersecting its baseline in latitude 39°06'40?N and longitude 108°33'20?W from Greenwich.

6th Principal Meridian

Source: United States Geological Survey, the National Map, The Public Land Survey System (PLSS) The USGS serves the Nation by providing reliable scientific information to describe and understand Earth; minimize loss of life and property from natural disasters; manage water, biological, energy, and mineral resources; and enhance and protect our quality of life.

Land Survey Section, Quarter and Lot Locations

Basic Township Map
How are sections numbered? Townships 6 miles tall and 6 miles wide are divided into Sections each 1 mile tall and 1 mile wide. Each section contains about 640 acres.

The sections are numbered starting in the northeast corner of the township with section 1 and ending in the southeast corner with section 36.

Sections 16 and 36 of every township were deeded to the State of Colorado when Colorado was formed. Section 16, the school section, was leased to generate funds to support public schools. Section 36 was leased to fund state government operations.

Some other sections and parts of sections in Washington County were also transferred to state ownership when the state was formed in 1876.

Section MapWhat are Half-Sections, Quarters, 80s, 40s? For the purposes of describing land locations, each section is subdivided into quarter-sections of 160 acres. The "Quarters" are subdivided into forty acre plots known as "40s". While not often used in Colorado, each "40" can be further subdivided into four 10 acre square plots and the 10 acre plots subdivided into 2½ acre square plots.

A half-section is two adjoining quarter-sections. An "80" is two adjoining 40 acre subdivisions.

To illustrate the system, the "forty" that was deeded by A.J. Miller to the Vernon town council in 1892 for the Vernon townsite in Yuma County was described as the NW¼ NW¼ Section 28, Township 1 South, Range 44 West of the Sixth PM.

40 Acre Lot LocationsWhat are Lots? Since the Earth is curved and townships were surveyed using the curved lines of latitude and longitude, compromises have to be made to fit in 36 sections, each legally defined as a 5280 foot square. Under the land survey laws all "errors" in section size were pushed into the 11 sections in the northern and western tiers of the township - sections 1-6, 7, 18, 19, 30 and 31. Those sections always contain more or less than 640 acres.

When the local survey was made to establish internal section divisions the same "push the error north and west" rule was applied. In the 11 problem sections the "40s" along the north and west sides of the section are all larger or smaller than 40 acres and are designated "Lots".

The legal description for the northeast quarter of section 4 in the illustration would be "160 acres more or less consisting of Lot 1, Lot 2 and the S½ NE¼ of Section 4".

The land survey rules break down in areas where settlers agreed on their own land divisions before the official government surveyor defined the section lines. In these areas the "lots" depart from the Rectangular Survey descriptions and use "Meets and Bounds" descriptions.

Back to Washington County Land Survey Townships

These pages are © 2002 & 2008 Lee C. Zion