SURVEYOR-GENERAL'S DIRECTION NUMBER 1

ISSUED PURSUANT TO REGULATION 27 OF THE SURVEY ACT 1992

ACCURACY OF SURVEYS

1. Application of this Direction

Pursuant to Regulation 16 of the Regulations under the Survey Act 1992, this Direction details the standards of accuracy required for cadastral surveys.

2. Definitions

"Adelaide City Core, Frame and Residential Districts" means those Districts so defined in the Principles of Development Control of the City of Adelaide Plan under the Development Act 1993.

"MGA" means the Map Grid of Australia 1994 specified in the GDA Technical Manual of the Intergovernmental Committee on Surveying & Mapping.

"Commercial Area" means an area designated primarily for shopping, commercial or business use in the Development Plan under the Development Act 1993, or land actually or intended to be used for such purposes.

"Rural Area" means an area of land not within an urban area, the Adelaide City Core, Residential of Frame Districts or a Commercial Area.

"Urban Area" means an area of land that includes an allotment or lot that is one half of a hectare or less in area or has a boundary with such an allotment or lot but excludes the Adelaide City Core, Frame and Residential Districts and Commercial Areas.

3. Perimeter Misclosure

Where the accuracies of surveys are tested by perimeter misclosure, the misclosure shall not exceed the following limits:

(a) on surveys in the Adelaide City Core District: 0.02 metres plus one part in 15 000

(b) on surveys in Commercial and Adelaide City Frame and Residential Districts: 0.02 metres plus 1 part in 10 000

(c) on urban surveys: 0.03 metres plus one part in 10 000

(d) on rural surveys: 0.10 metres plus one part in 5 000

4. Connection to Coordinated Survey Marks

Where the survey is connected to permanent or State survey marks for which the MGA coordinates are known to 4th order or better, the linear misclosure and displacement (caused by the angular misclosure) between the survey and the MGA coordinates of the permanent or state survey marks must not exceed:

4.1 Linear Misclosure

(a) on surveys in the Adelaide City Core District: 0.02 metres plus one part in 15 000

(b) on surveys in Commercial and Adelaide City Frame and Residential Districts: 0.02 metres plus 1 part in 10 000

(c) on urban surveys: 0.03 metres plus one part in 10 000

(d) on rural surveys: 0.10 metres plus one part in 5 000

4.2 Displacement Caused by the Angular Misclosure

(a) on surveys in the Adelaide City Core District: 15" + 0.02 metres

(b) on surveys in Commercial and Adelaide City Frame and Residential Districts: 20" + 0.02 metres.

(c) on urban surveys: 20" + 0.03 metres

(d) on rural surveys: 40" + 0.10 metres

5. Positional Accuracies

5.1 Where the MGA Coordinates of Survey Marks Known to 4th Order or Better

Where surveys are carried out using coordinate based techniques or verified radiations (where linear misclosure and displacement cannot be tested), and the survey is connected to permanent or state survey marks, the MGA coordinates of which are known, the position of survey marks as placed or accepted in the survey and the position of those marks as determined from their MGA coordinates must not differ by more than:

(a) on surveys in the Adelaide City Core District: 0.02 metres

(b) on surveys in Commercial and Adelaide City Frame and Residential Districts: 0.03 metres.

(c) on urban surveys: 0.05 metres

(d) on rural surveys: 0.15 metres.

5.2 Where the MGA Coordinates of Survey Marks Not Known to 4th Order or Better

Where surveys are carried out using coordinate based techniques or verified radiations (where linear misclosure and displacement cannot be tested), and the survey is connected to state survey marks, the MGA coordinates of which are not known, the difference in the position of survey marks as placed or accepted in the survey and the position of those marks as determined from measurements shown on the plan (including measurements relating to the State survey marks) must not differ by more than:

(a) on surveys in the Adelaide City Core District: 0.02 metres

(b) on surveys in Commercial and Adelaide City Frame and Residential Districts: 0.03 metres.

(c) on urban surveys: 0.05 metres

(d) on rural surveys: 0.15 metres.