Niue's Territorial Sea Baseline was derived using the IKONOS satellite imagery taken in 2004 and Horizontal Datum used was the World Geodetic Datum 1984 (WGS 84) as stipulated under Section 12 of the Maritime Zones Act 2013.
The Marine Zones (Declaration) Act 2011 states that "Baseline" means the baseline from which the breadth of the territorial sea, contiguous zone, exclusive economic zone and continental shelf is measured. It contains the geographic coordinates that defines the baseline for the Line Group. The points are defined by geographic coordinates are determined by reference
to the World Geodetic System 1984 (WGS 84).
The Marine Zones (Declaration) Act 2011 repeals the Marine Zones (Declaration) Act 1983. It states that the territorial sea of Kiribati comprises those waters having, as their inner limits, the baseline of Kiribati and, as their outer limits, a line measured seaward from that baseline, every point of which is at a distance of twelve (12) nautical miles from the nearest point of the baseline.