Public Lands and Subdivision Map Act
Public Land Survey System
California's federal lands were subdivided from a principal meridian and base line into townships six miles square containing 36 sections of nominally 640 acres, numbered from the northeast corner (section 1) boustrophedon to section 36 in the southeast. Standard parallels or correction lines, generally every four townships, control for meridian convergence. Retracement rules: original corners control; a lost corner is restored by single proportionate measurement between the nearest accepted corners; double corners occur where section and quarter-section corners were set on opposite sides of a correction line. Meander lines along water approximate the water's edge for area computation and are not boundaries.
Subdivision Map Act
The Subdivision Map Act (Gov. Code section 66410 et seq.) sets minimum statewide standards: tentative and vesting tentative maps, parcel maps for four or fewer lots, final maps, lot line adjustments, and reversion to acreage. Local ordinances supply procedures and standards. Monuments must be set as the Act and local ordinance require, with limited deferral, and the map must show them. Tentative map approval generally runs 24 months plus statutory extensions.
Traps
- Treating the tentative map's approval period as the final map's or ignoring extensions.
- Calling a two-lot split a 'minor subdivision' - the term is obsolete.
- Using a meander line as a boundary.
- Forgetting that parcel maps also serve condominium conversions and that lot line adjustments are not subdivisions.
Worked example
A lost quarter corner lies between two found section corners recorded 5,280.00 ft apart but now measuring 5,270.00 ft. Single proportionate measurement places it at 5,270.00 x (2,640 / 5,280) = 2,635.00 ft from the south corner - not 2,640.00 ft.
Rule of thumb
Retracement proportions use record distances as the ratio; you measure the found corners, you do not move them.