9.3 The Rectangular Survey System

The Rectangular Survey System

The rectangular survey system (government survey method) was developed to standardize property descriptions, especially for large tracts of land in the Midwest and West. It uses latitude (east-west) and longitude (north-south) lines to create uniform grids of squares (townships).

Key elements:

• Principal meridian: Main north-south line for survey reference (see map above).
• Base parallel (base line): Main east-west reference line.
• Range: North-south strip between meridians (6 miles wide).
• Tier: East-west strip between parallels (6 miles wide).
• Township: 6-mile by 6-mile square formed by intersecting ranges and tiers (36 square miles).

Sections of a Township: Each township is divided into 36 sections, each 1 mile by 1 mile (1 square mile, 640 acres). Sections are numbered in a unique order, starting at the northeast corner.

• Sections can be subdivided into halves, quarters, etc. (e.g., SW 1/4 of a section = 160 acres).
• To convert section fractions to acres: Multiply the denominators and divide 640 by that number (e.g., E 1/2 of SW 1/4 of SW 1/4 = 640 / (2×4×4) = 20 acres).
• Best for describing square/rectangular properties; irregular shapes may require metes and bounds or plat method.

Check-In Questions

• How many acres are in one section of a township?
  640 acres
  160 acres
  36 acres
  6 acres
  Show Answer

  Correct Answer: 640 acres
  Each section is one square mile, or 640 acres.
• What is the formula to find the acreage of a section fraction?
  Divide 640 by the product of the denominators
  Multiply 640 by the numerators
  Add the denominators
  Subtract 36 from 640
  Show Answer

  Correct Answer: Divide 640 by the product of the denominators
  Example: E 1/2 of SW 1/4 of SW 1/4 = 640 / (2×4×4) = 20 acres.

Recorded Plat Method (Lot & Block System)

The recorded plat method is used for properties in subdivisions. Land is surveyed and divided into lots (and sometimes blocks), then mapped on a subdivision plat. The plat map is recorded in the county, and lot/block numbers become the legal description.

• Common for residential, commercial, and industrial subdivisions.
• Plat must comply with local standards and be officially recorded.
• The full legal description includes lot, block, subdivision name, section, township, county, and state.

Example:
“Lot 7, Block 8 of the Panther Ridge, the Forest Subdivision of the SE 1/4 of Section 35, Township T28S, R19E of the Tallahassee Principal Meridian in Manatee County, Florida.”

Check-In Questions

• What does the recorded plat method use to describe property?
  Lot and block numbers from a subdivision plat map
  Only street addresses
  Metes and bounds only
  Township and range only
  Show Answer

  Correct Answer: Lot and block numbers from a subdivision plat map
  The plat method is also called the lot and block system.
• What must a recorded plat legal description include?
  Lot, block, subdivision, section, township, county, and state
  Just the street address
  Only the lot number
  Only the subdivision name
  Show Answer

  Correct Answer: Lot, block, subdivision, section, township, county, and state
  The full legal description is comprehensive and precise.