NSW Coastline data is linear feature class defining the line of contact between a body of water and the land. In particular, the line delineating the interface between land, internal waters and the “Territorial Sea” as defined by the Seas and Submerged Lands Act - No. 161 of 1973.

The coastline defining Mean High Water Mark (MHWM) does not include MHWM within estuaries. Features within coastline feature class include: mean high water mark and mean low water mark.