State Offshore Minerals Act 2003 (Western Australia)
The Offshore Minerals Act 2003 (and consequential amendments to the Mining Act 1978) commenced operation on 1 January 2011 and fulfils this State's commitment to an agreement made between the Commonwealth and States under the Offshore Constitutional Settlement Agreement of 1979. This agreement provided for a legislative regime to be established for Australia’s sea and seabed areas.
Mineral exploration and recovery is governed by state legislation for the first three nautical miles and this legislation is to mirror (as much as possible) Commonwealth legislative for Australia's territorial sea beyond the three nautical miles. The three nautical miles of the State's Offshore Minerals Act 2003 is known as "coastal waters". The Commonwealth territorial sea is known as the "adjacent area". The three nautical mile strip commences from the baseline to the adjacent area as defined in Section 16(1) of the Offshore Minerals Act 2003. The inner waters from land to the baseline remain under the jurisdiction of the Mining Act 1978.
Generally, the baseline is the lowest astronomical tide along the coast of islands and the mainland. It also includes lines connecting islands, lines connecting islands and the mainland, lines enclosing bays and coastal indentations that are not bays but depart from the coast. It is a nominated line that generally constitutes the mean low water mark, but also goes across bays and around offshore islands and is depicted on the department's TENGRAPH® Online mapping system.
A plan is available showing the three legislative jurisdictions for Western Australia
Prior to the introduction of the State's Offshore Minerals Act 2003 the Mining Act 1978 applied to the land area of the State and, by arrangement with the Commonwealth, the first 3 nautical miles of the territorial sea from the baseline.