Cadastral surveying
Cadastral surveying
Cadastral surveying in the S+SNZ Geodetic Survey exam tests how New Zealand boundaries are defined, reinstated, recorded and checked. The surveyor's job is not to invent coordinates but to locate and document the legally defined boundary within the cadastral survey dataset (CSD), using Landonline and the Cadastral Survey Act 2002 framework.
Core rules and concepts
- A boundary is defined by the cadastral survey and supporting record, not by a single coordinate.
- Reinstatement starts from undisturbed original marks; evidence of disturbance must be recorded.
- The CSD must be internally consistent, connected to the geodetic network, and accompanied by a survey report explaining decisions.
- Accuracy is assessed against the applicable cadastral accuracy standard; redundant measurements and misclose checks are expected.
- Tenure, parcel intent, encumbrances and survey plan diagrams must agree.
Worked example
An old boundary runs from mark A to mark B. The record gives 20.000 m on bearing 90°00'00". You measure 19.988 m on 89°59'50". The vector misclose is about 0.012 m, with a small angular component. If the applicable required accuracy for this survey is 0.020 m, the measurement is acceptable as a check, but it does not by itself prove the boundary. You would compare both marks, check their condition and provenance, test against other nearby marks, and record the difference and reasoning in the survey report before adopting the reinstated line.
Traps
Treating a disturbed mark as original; using one mark without a check; quoting coordinates as the boundary; ignoring the survey report; mixing geodetic and cadastral coordinates without transformation; and failing to reconcile tenure, parcel area and diagram.