11Australian Geodetic Datum prescribed for limited purposes (Act s. 10)

11.Australian Geodetic Datum prescribed for limited purposes (Act s. 10)

(1)Despite regulation 10, the AGD is the prescribed datum for the purposes referred to in —

(a)section 10(5) of the Act (which refers to the determination of the position on the surface of the Earth of the boundary of the area described in Schedule 2 to the Act); and

(b)section 17(4) of the Act (which refers to the determination of the position on the surface of the Earth of a graticular section or a block).

(2)The AGD is defined by an ellipsoid having a semi‑major axis (equatorial radius) of 6 378 160 m and a flattening of 1/298.25 and fixed by the position of the origin being the Johnston Geodetic Station in the Northern Territory of Australia.

(3)The Johnston Geodetic Station is taken to be situated at —

(a)25° 56′ 54.5515″ south latitude and 133° 12′ 30.0771″ east longitude; or

(b)where decimal reckoning is used, 25° 56.90919′ south latitude and 133° 12.50129′ east longitude,

and to have a ground level elevation of 571.2 m above the ellipsoid referred to in subregulation (2).

(4)An instrument in force under the Act or these regulations immediately before 16 December 2000 that contains a reference to the position on the surface of the Earth of a point, line or area determined by reference to the AGD is to be endorsed, if it is practicable to do so, with a statement to the effect that the AGD applied to that determination, but the omission of such a statement does not affect the validity of the instrument.

(5)If, in relation to an instrument referred to in subregulation (4), coordinates calculated by reference to the AGD are to be converted to coordinates calculated by reference to the GDA, the conversion is to be made using the National Transformation Version 2 (NTV2) grid file transformation.

[Regulation 11 inserted: Gazette 15 Dec 2000 p. 7218; amended: SL 2025/172 r. 22.]