Township and Range System

Accuracy of map location can be enhanced for any area surveyed under the township and range system of the Bureau of Land Management. The combination of a topographic map and this system can be used to locate features within a few acres and is a primary means of subdividing tracts of land for sale. The organization of the township-section system is based on the definition of base lines and principle meridians (see Figure 7.3A). The position of a base line and meridian within a region may or may not coincide with latitude and longitude. Townships are areas of 6 miles on a side (36 sq. mi), bordered on the east and west by range lines and on the north and south by township lines. Each township is subdivided into 36 sections of 1 mile on a side (Figure 7.3B). The numbering of township and range lines begins with respect to regional base lines and meridians (Figure 7.3A). Notice that the numbering system of sections follows a slightly unusual but consistent pattern. In areas surveyed under this system, roads and fence-lines typically lie in north-south and east-west orientation. Roads normally define the boundaries of sections (1 mi sq. and 640 acres) and fences may mark half-sections ( mi sq. and 160 acres), quarter-sections ( mi sq and 40 acres), etc. The designation for quarter-sections are the quadrants of a compass (NE, SE, SW, NW). if greater accuracy is desired, quater-sections can be subdivided quarters and so forth. The correct statement for the location of the quarter-quarter-section indicated in Figure 7.3D would be: the northeast quarter of teh southeast quarter of section 36, township 2 north, range 2 east, county name (e.g. Potter County), state (e.g. Texas). In the state of Texas, this system applies only to the panhandle region of northwest Texas. The panhandle region of Texas was surveyed under this system, but the remainder of the state was surveyed or boundaries decided on the basis of the Spanish land grant system. All of the midcontinent north of Texas has been surveyed under the township and range system.

Figure 7.3

 
 
 
 
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