Rules relating to referenced CSDs and bearing corrections
The RCS 2010 require that a CSD must include:
- a list of CSDs used in the determination of the survey. Rule 9.1(a).
- any bearing adjustments applied to each CSD from which a bearing was adopted in the CSD. Rule 9.3(b).
- a survey report that contains the basis for any bearing adjustment applied to an adopted bearing. Rule 8.2(a)(iii).
The term ‘bearing correction’ as used in the Landonline survey header and vector capture of a CSD means the same as ‘bearing adjustment’ in RCS 2010. The purpose of a bearing adjustment is to provide a consistent orientation correction to adopted bearings to satisfy rule 4.1.
While it is useful to list in the survey header all referenced CSDs used in the determination of a particular CSD, referenced CSDs that have not been assessed for bearing correction will by default have a bearing correction of 0°00’00” allocated to them.
This could lead future users of the survey header into thinking that a referenced CSD with a 0°00’00” bearing correction has been assessed and determined as not requiring a bearing correction.
To avoid misinterpretation one of the following options are suggested:
- Assess and report on a bearing correction for all referenced CSDs in the survey header, whether a referenced CSD has been used as an adoption source or not.
- Only capture referenced CSDs in the survey header that have been used as an adoption source and report on the basis for applying any bearing adjustments applied.
Please note: In relation to the application of Rule 8.2(a)(iii) the survey report must include a clear description of the basis for determining a bearing adjustment, rather than just a statement that a bearing correction has been applied.
Whenever reviewing an existing CSD for applied bearing adjustments, it is prudent to independently verify any bearing correction shown in the survey header by referring to the survey report for that CSD or by comparison to other related CSDs.
Prepared by: Cadastral Surveyors Group, Property Rights