Seas and Submerged Lands Act 1973 - Proclamation under section 7(1) (04/02/1983)

The Proclamation operates on a small set of legal and geodetic concepts. Those concepts , defined and used in the document , are the tools by which territorial sea limits are fixed. They are:

• Territorial sea limits declared under s 7(1) of the Seas and Submerged Lands Act 1973. The instrument explicitly invokes the Act as the source of the Governor‑General’s power to make the declaration (preamble). It also frames the declaration so as not to be inconsistent with Part I, Section II of the 1958 Convention on the Territorial Sea and the Contiguous Zone (preamble). The legal concept is therefore the outward limit of the territorial sea, measured in relation to baselines and breadths permitted by the Convention.

• Geodetic reference system. Clause 1(2) requires that positions be determined by reference to the Australian Geodetic Datum, specifying the spheroid parameters (centre at Earth's centre; major radius 6,378,160 metres; specified flattening symbol in the text) and the precise coordinates and ground level of the Johnston Geodetic Station (Latitude 25°56′54.5515″ S; Longitude 133°12′30.0771″ E; ground level 571,2 metres above the spheroid). The instrument therefore requires any positional determination to use those datum parameters, not ad hoc or unspecified local approximations.

• Unit of measurement. Clause 1(1) defines "mile" as the international nautical mile, 1,852 metres. The schedules repeatedly use arcs of radius "3 miles", so the numerical radius is 3 × 1,852 metres = 5,556 metres, and any charting or surveying must use that conversion.

• Geodesic lines. Several schedules instruct that the outer limit is "running thence along the geodesics successively joining the following points" and then list coordinates. "Geodesics" on the spheroid defined in clause 1(2) indicates shortest‑distance curves on that spheroid between listed coordinates. The Proclamation therefore requires geodesic computational methods rather than, for example, simple planar straight lines or rhumb lines.

• Intersecting arcs of circles. Other schedules define the limit as a "series of intersecting arcs of circles having a radius of 3 miles and drawn successively from the following points." In that construction the listed coordinates are the centres of the arcs; the outer limit is the locus of points that are 3 nautical miles from successive centres and where those arcs intersect, producing a closed curve enclosing the island(s).

• Low‑water line at Lowest Astronomical Tide. Clause 4 uses the maritime standard "low‑water line at Lowest Astronomical Tide" to fix an inner limit for part of the Pearce Cay area. That is a conventional baseline concept: the shoreline at the lowest predictable tide, as opposed to mean sea level or a tidal datum.

These concepts create the mechanism by which the Proclamation converts geographic coordinates and radii into legally significant lines. They also create technical dependencies: practitioners must use the specified spheroid and Australian Geodetic Datum, must be comfortable calculating geodesics on that spheroid, and must interpret 'intersecting arcs' correctly. Any error or ambiguity in those geodetic inputs cascades into the map‑level position of the declared outer limits. The Proclamation uses precise numeric coordinates and formal geometric constructs rather than narrative descriptions, which reduces ambiguity in principle but increases reliance on accurate transcription, datum conformity and competent geodetic computation in practice.

The Proclamation affects any person or entity whose legal rights, duties or activities are conditioned by the location of the territorial sea adjacent to the listed islands. That group includes, at minimum:

• Commonwealth and State regulatory agencies. The Proclamation gives the Commonwealth the legal instrument to mark the extent of the territorial sea under the Seas and Submerged Lands Act 1973 (preamble and s 7 authority) adjacent to islands "comprised within the State of Queensland" (clause 2 preface). Agencies responsible for maritime safety, fisheries, customs, immigration, environmental regulation, offshore petroleum regulation and maritime policing will use the declared lines to determine whether specific waters fall inside or outside the territorial sea and thus which regulatory regime applies.

• The State of Queensland. The islands identified are described as "comprised within the State of Queensland" (clause 2). The State will be affected because the territorial sea limits adjacent to those islands influence the spatial reach of Commonwealth and State competencies and may require coordination between state and federal agencies responsible for services and law enforcement in those waters.

• Mariners and shipping operators. Commercial and recreational vessels transit and operate in waters near the listed islands. The Proclamation changes the geographic point at which a vessel enters Australian territorial waters adjacent to those islands. That has practical consequences for compliance with national laws (for example, immigration, customs, policing and safety requirements that operate in territorial waters rather than the high seas). The Proclamation’s coordinates and arc constructions must be reflected in nautical charts and notices to mariners.

• Fishers and fisheries businesses. The location of the territorial sea affects licensing, quotas, and authority to regulate fishing. Operators must know whether a given operation is within Australian territorial waters adjacent to these islands, and therefore under Australian fisheries regulation, or outside those lines.

• Resource explorers and operators. Entities contemplating seabed exploration, seabed installations or seabed resource extraction will need to know whether planned activities fall inside the declared territorial sea limits. The Proclamation supplies the legal boundaries that will be used to determine jurisdiction for any required permits or leases.

• Indigenous and local communities. Residents of the named islands and adjacent communities will be affected in administrative and practical ways. The Proclamation sets the outer maritime limit that defines the immediate marine jurisdiction around their islands.

• Chartmakers, hydrographers and surveyors. The effect of the instrument is technical: it requires geodetic computations using the Australian Geodetic Datum as specified (clause 1(2)) and the plotting of geodesic lines and arcs of specified radius. Hydrographic offices, chart producers and surveyors must implement those rules to produce authoritative charts.

• Neighbouring states and international navigators. Although the Proclamation itself does not name neighbouring countries, the declaration is expressed as required to be "not inconsistently with Section II of Part I of the Convention on the Territorial Sea and the Contiguous Zone" (preamble). Consequently, any third state whose ships operate near these islands will see a change in the legally declared outer limits Australia uses, and that may affect freedom of navigation claims, passage rights or operational planning.

Who pays and who decides. The Commonwealth decides the lines (Governor‑General with advice of the Federal Executive Council), acting under s 7(1) and (2) of the Act (preamble). The immediate costs mainly fall on governmental budgets (hydrographic updating, chart publication, agency operational adjustments) and the private actors who must comply with regulatory requirements when the practical effect of crossing a declared line changes their obligations. Indirect costs fall on parties who must reconfigure operations to comply with Australian jurisdiction where it did not previously apply or to understand the new limits for licensing and commercial purposes.

The Proclamation does not itself create operational statutory duties or criminal offences. Instead it creates spatial facts that trigger duties and rights found elsewhere: it fixes where the territorial sea exists adjacent to the named islands so that substantive laws that depend on the location of the territorial sea become applicable. The key legal effects and consequential duties/rights that flow from the Proclamation are therefore structural and enabling.

• Duty to use specified geodetic references in positional determinations. Clause 1(2) requires that, for purposes of the Proclamation, positions are determined by reference to the Australian Geodetic Datum as detailed, including the spheroid parameters and the Johnston Geodetic Station coordinates. Practitioners plotting or measuring these limits therefore have a duty to adopt that geodetic framework when interpreting the schedules.

• Right of the State to exercise jurisdiction within the declared limits. By declaring outer limits of the territorial sea under the authority of s 7 of the Seas and Submerged Lands Act 1973 (preamble), the Proclamation identifies the geographic area in which Australia may exercise the rights and duties that attach to a territorial sea as provided for under the Convention and domestic law. The Proclamation itself does not itemise those rights, but it creates the spatial precondition for their exercise (for example, application of customs and immigration law, fisheries management and law enforcement by Australian authorities).

• Duty on chartmakers and navigational services to update authoritative charts. The schedules consist of precise coordinates, geodesics and circles of 3 nautical mile radius. Official nautical charts and navigational publications will be expected to reflect those lines; charting authorities therefore have an operational duty to incorporate the Proclamation’s instructions.

• Practical duties for marine operators. Operators must determine whether their activities fall within the declared territorial sea. If so, they become subject to the set of Australian laws that apply in territorial waters. The Proclamation therefore serves as a switch that turns on a cluster of legal duties (licences, permits, tax or fee obligations, reporting, safety requirements), even though it does not list them.

• Duty to interpret arc constructions and geodesics according to the specified definitions. The schedules draw the outer limits using a combination of geodesic segments and intersecting circular arcs of radius "3 miles" drawn from listed centres. Those are technical instructions; users must interpret "3 miles" as 3 international nautical miles (clause 1(1)) and compute geodesics on the spheroid in clause 1(2)(a).

• Rights of affected jurisdictions. The Proclamation identifies the islands as islands "comprised within the State of Queensland" (clause 2). That descriptive choice affects allocation of responsibilities between Commonwealth and State agencies for delivery of services and law enforcement. The Proclamation itself does not change the ownership of islands; it sets maritime boundaries adjacent to islands within Queensland.

What the Proclamation does not do. It does not itself specify enforcement powers, penalties, permit regimes, or administrative procedures for the exercise of the rights it helps define. Those substantive duties and penalties are contained in other instruments and statutes. The Proclamation is a definitional and technical instrument: it creates the spatial basis on which substantive law operates.

The Proclamation does not contain penalty provisions or prescribe enforcement mechanisms. It is a declaratory instrument that fixes geographic limits; enforcement must be undertaken under other laws and administrative powers. The key source passage is the preamble invoking s 7(1) and s 7(2) of the Seas and Submerged Lands Act 1973 as the Governor‑General’s authority to "declare" limits. The Act will therefore be the statutory source of broader powers and enforcement regimes, but the Proclamation itself is silent on sanctions.

Practical enforcement mechanisms and who enforces will therefore be determined by the substantive Commonwealth and State statutory regimes that apply within territorial waters. Those regimes typically include:

• Administrative regulation and licensing schemes (for fisheries, environment, petroleum and seabed activities), where administrative agencies issue permits, apply fees and supervise compliance. The Proclamation’s effect is to determine whether those schemes apply to a given location.

• Criminal and civil enforcement under relevant statutes. Offences that apply in territorial waters are prosecuted under the applicable Commonwealth or State statutes. The Proclamation fixes the boundary used to determine whether an offence was committed in the territorial sea.

• Operational enforcement by maritime authorities. Maritime police, customs, border protection and naval assets conduct patrols and boardings in territorial waters. The Proclamation supplies the geographic definition for those operations.

Because the Proclamation is a boundary instrument, enforcement risk and burden are operational rather than normative: agencies and courts must apply other laws to activity within the defined waters. The absence of specified penalties in this instrument creates an implementation dependency: those seeking to enforce must be able to point to the substantive statute authorising enforcement in the defined area.

Implementation risks and compliance uncertainty. The Proclamation’s technical form creates specific enforcement challenges. Accurate enforcement depends on precise charting and geodetic computation. Any uncertainty about datum, transcription errors in the schedules, or ambiguity in interpreting "geodesics" versus alternative lines could lead to disputes about whether a particular vessel was within the territorial sea at a given moment. Enforcement at sea also involves the logistics of monitoring areas beyond immediate sight of shore. The Proclamation lowers legal uncertainty about where the territorial sea outer limits are, but only if the coordinates and geometric instructions are correctly rendered on charts and navigational products and if agencies are resourced to monitor and enforce in those areas.

For practical purposes the Proclamation is a foundational instrument; the immediate legal consequences (including penalties) flow from other statutory provisions that apply to the declared territorial sea, not from the Proclamation text itself.

The Proclamation is an implementing instrument that interacts functionally with a web of domestic and international legal regimes through its primary effect: fixing the spatial limits of the territorial sea adjacent to specified islands. The text explicitly ties itself to the 1958 Convention on the Territorial Sea and the Contiguous Zone by requiring declarations "not inconsistently with Section II of Part I of the Convention" (preamble). In practical terms that framing produces a range of interactions:

• Interaction with the Seas and Submerged Lands Act 1973. The Proclamation is made under s 7(1) and (2) of that Act (preamble). The Act supplies the statutory authority for the Governor‑General to declare breadths and baselines. The Proclamation exercises that power by listing precise coordinates and geometric methods. Any legal consequences deriving from the existence of the territorial sea , for example, jurisdictional questions or allocation of responsibilities , will be determined under the Act and related statutes.

• Interaction with the Convention. The Proclamation is constrained by the Convention's rules on baselines and breadth (acknowledged in the preamble). By stating that the declaration is not to be inconsistent with Section II, the instrument signals that its geometric constructs (geodesic segments, 3‑mile arcs, low‑water baselines) are intended to conform to accepted international standards for territorial sea measurement. This is relevant for international law questions such as innocent passage or navigation rights.

• Interaction with State boundaries and functions. The Proclamation identifies the islands as "comprised within the State of Queensland" (clause 2). That description interacts with State responsibilities, especially where State statutes or functions apply to coastal waters adjacent to State islands. The Proclamation does not alter island ownership; it determines the Commonwealth’s declaration of the breadth and baselines that will be used to measure the territorial sea adjacent to those islands.

• Interaction with operational statutes. Many domestic statutes apply differentially depending on whether water is within the territorial sea, the contiguous zone, or beyond. By formally identifying the outer limit of the territorial sea adjacent to the named islands, the Proclamation becomes the spatial reference for applying statutes in the domains of customs, immigration, fisheries, environmental protection, navigation safety, and offshore resource regulation. The Proclamation itself does not list those statutory interactions; it creates the spatial fact to which those statutes refer.

• Interaction with charting and navigational standards. Clause 1(2) prescribes the Australian Geodetic Datum and a spheroid as the basis for position determination. That interacts with hydrographic and charting law and practice: official charts, notices to mariners and electronic navigational charts must reflect the geodetic basis and the declared lines. Any law or regulation that references an official chart will therefore depend on the Proclamation’s geometries being correctly implemented in charting products.

• Potential interaction with international disputes or negotiations. While the Proclamation refuses to be inconsistent with the Convention, it nevertheless produces a declared limit that could interact with the maritime claims of other States if any were proximate. The Proclamation does not mention neighbouring States, but in practice territorial sea declarations near international boundaries can be the subject of bilateral negotiation and, if contested, dispute settlement. The Proclamation is thus a unilateral legal declaration, albeit one framed to conform to the Convention.

Because the Proclamation is a spatial definitional act, its most important legal interactions are as the reference layer for other laws. The schedules and datum definitions become inputs into any statute, regulation, administrative decision or enforcement action that turns on the legal status of particular waters.

The text of the Proclamation, as provided, records a single instrument made by the Governor‑General on 4 February 1983 with effect on and from 14 February 1983 (closing recital and operative clause). It cites the authority of sub‑sections 7(1) and 7(2) of the Seas and Submerged Lands Act 1973 in the preamble. The Proclamation itself contains no express amendment provisions, revocations of prior proclamations, or schedules indicating later alterations.

What the source shows and what it does not. The source gives no history of prior or subsequent amendments to this Proclamation. It contains no footnotes, marginal notes or editorial insertions indicating that any schedule has been varied, corrected or superseded. The instrument therefore stands, in the provided text, as an original 1983 proclamation; any later amendment, replacement proclamation, or legislative revision would appear separately in the legal record but is not present in the current text.

Practical implications of the single‑instrument record. Users should note that the Proclamation defines a geodetic basis tied to the Australian Geodetic Datum and specific spheroid parameters current as at the time of drafting (clause 1(2)). Geodetic practices in Australia have since evolved (for example to modern datums), and later legal instruments sometimes restate or update datum references. Because the Proclamation does not itself include an updating mechanism or transitional provision for later datums, any later administrative practice or amended proclamation that changes the datum or redefines lines would need to be located in the statutory record. The absence of amendment clauses here implies that, in legal effect, the coordinates and datum specified remain the authoritative record until or unless altered by subsequent proclamation or legislative amendment pursuant to s 7.

Audit advice. Anyone relying on this Proclamation for operational, regulatory or legal purposes should verify that no subsequent proclamations, corrections, or legislative changes have been made since 1983. The instrument itself is silent on that point and does not contain internal markers of amendment. Official repositories (Commonwealth Gazette, National Archives, or the relevant departmental records) should be checked for any later instruments that modify, confirm or supersede the schedules or datum references in this 1983 Proclamation.

The Proclamation text contains no reference to litigation, judicial consideration or declaratory proceedings. It does not cite any cases and, within the provided source, no legal challenges or court outcomes are recorded. That absence of litigation material in the text means that any assessment of legal disputes connected to this Proclamation must be made by external research in court records and legal databases; such research is not represented within the document itself.

Potential litigation vectors implicit in the instrument. Although the Proclamation itself is silent on litigation, its substantive subject matter , boundaries of the territorial sea , is the type of legal measure that can give rise to disputes, including:

• Interpretation disputes about the correct application of the schedules. Courts might be asked to determine whether a particular set of coordinates or arc constructions was correctly implemented, or whether transcription errors in the published schedules affect legal limits.

• Disputes over datum and transformation. Clause 1(2) prescribes the Australian Geodetic Datum and a spheroid. Litigation could arise where parties challenge whether positional calculations have been made using the correct datum or spheroid constants, or whether modern datum conversions were appropriately applied.

• Enforcement and jurisdictional disputes. If an enforcement action were taken against a vessel or person based on presence within the declared territorial sea, that action could prompt litigation on whether the vessel was in fact within the territorial sea as declared by the Proclamation.

• International dispute scenarios. If another State were to claim competing maritime entitlements in proximate waters, that could give rise to diplomatic dispute or international litigation. The Proclamation does state it is to be "not inconsistently with" the Convention; nevertheless, unilateral declarations concerning maritime limits can be contested by other States.

What to do in practice. Because the Proclamation contains no litigation history, counsel or practitioners relying on it should conduct independent searches of Commonwealth and State court records, the Federal Court of Australia, the High Court and any relevant international arbitration records to see whether this particular Proclamation, or disputes around these geographic areas, have been litigated. Absent such external research, one must treat the Proclamation as an uncontested declaratory instrument, while recognising that legal contests remain a live possibility where enforcement or property rights are affected.

The Proclamation is precise, but it contains several textual and drafting features that can create practical ambiguity, transcription risk, and interpretive difficulty. The following are the main "gotchas" apparent from the source text itself; each is grounded in the text and may create implementation or legal uncertainty if not addressed.

• Datum and spheroid details. Clause 1(2)(a) specifies a spheroid with major radius 6,378,160 metres and a flattening symbol shown as an image placeholder (the text shows a missing or non‑rendered symbol). That missing flattening value in the published text is a critical geodetic parameter. Accurate computation of geodesics on a spheroid requires both the major radius and the flattening (or minor radius). The presence of a blank or non‑rendered flattening means that, as printed here, the spheroid definition is incomplete. Practitioners must obtain the correct flattening constant from original authoritative records or other official sources before performing geodesic calculations.

• Mixed numeric notation. Clause 1(2)(b) gives the Johnston Geodetic Station ground level as "571,2 metres", using a comma as a decimal separator rather than a point. This could lead to confusion , is it 571.2 metres (a plausible small decimal) or a typographic error? The source uses continental numeric punctuation in one instance while other numerals use standard Anglo punctuation. That inconsistency can cause misinterpretation.

• Typographical and transcription errors in schedules. Several schedule entries show likely typographical errors in degree/minute/second notation: examples include "9″32′39″" (double quote before degrees) in Schedule 5, "142°1701″" for Schedule 6 (xxiv), and entries such as "14°25′43″" in Schedule 7 where likely "141°" was intended. Some seconds and prime characters are doubled or misplaced (e.g., 142°16′11′′). Such errors will produce nonsense coordinates unless reconciled. Those inconsistencies are present in the text as provided and are a concrete risk: if official charts or legal arguments rely on literal reproduction of these entries without correction, positions could be misplaced.

• Ambiguity about whether listed points in arc schedules are centres or points on the limit. The schedules describe the outer limit as formed by "a series of intersecting arcs of circles having a radius of 3 miles and drawn successively from the following points." That language indicates the listed coordinates are the centres of the arcs. In practice, some readers could misread the lists as points on the limit itself rather than centres. Hydrographic interpretation must therefore be explicit: the listed points are arc centres from which a circle of radius 3 nautical miles is drawn.

• Interpretation of "geodesics" on the specified spheroid. The schedules that instruct "running thence along the geodesics successively joining the following points" demand computation of geodesic curves on the spheroid specified in clause 1(2)(a). Some practitioners may be tempted to compute great circles on a sphere or to use planar approximations. The Proclamation requires geodesic calculations on the named spheroid; failure to do so will yield positional errors.

• Discrepancy in Pearce Cay treatment. Clauses 3 and 4 treat the northern and southern parts of the Pearce Cay adjacent sea differently: the outer limit north of Latitude 9°33′00″ S is set by Schedule 8 (clause 3) while the inner limit of that part of the territorial sea adjacent to Pearce Cay that lies south of that parallel is declared to be the low‑water line at Lowest Astronomical Tide (clause 4). This bifurcation may be confusing in practice: mapping must reconcile the declared outer limit for the north sector with the inner low‑water baseline for the south sector, and users must not assume symmetry.

• Dependence on external charting. The Proclamation is a legal description, not a navigational chart. Users must rely on official hydrographic services to convert these descriptions into usable charts and electronic navigation products. Any delay or error in chart publication will directly impact mariners and regulators.

• No enforcement or penalty text. As noted earlier, the instrument does not specify who enforces, how, or what penalties apply. That is a legal gap only in the sense that practitioners must consult other statutes for enforcement details. The Proclamation is therefore only one piece of the legal puzzle.

Taken together, these gotchas mean that responsible users must not rely on a blind literal transcription of the printed schedules. Instead they should consult authoritative sources to resolve missing spheroid parameters, correct typographical errors, obtain official charts that implement the limits and confirm the intended meaning of arc‑centre lists and geodesic segments.

Compliance with the Proclamation is twofold: technical compliance in translating the schedules into accurate cartographic and navigational products, and legal compliance in ensuring activities are lawful where the Proclamation causes jurisdictional change. Below are practical steps for different actors to achieve compliance, each grounded in the Proclamation text.

For hydrographic offices and chartmakers

• Use the datum and spheroid in clause 1(2). Positions "for the purposes of this Proclamation" must be determined by reference to the Australian Geodetic Datum and the spheroid whose major radius is given, and by reference to the Johnston Geodetic Station coordinates. Obtain the missing flattening constant from authoritative Commonwealth records where the printed text omits or garbles it. Do not substitute a different datum unless a later official instrument makes a lawful change.
• Compute geodesics on the specified spheroid between listed coordinates where schedules call for "geodesics successively joining the following points." Use geodetic software that supports an oblate spheroid with the supplied parameters.
• Where a schedule specifies "intersecting arcs of circles having a radius of 3 miles and drawn successively from the following points", treat the listed coordinates as centres and draw circular arcs of radius 3 international nautical miles (clause 1(1)). Ensure that arcs intersect and form a continuous closed curve enclosing the island(s).
• Rectify typographical anomalies before chart publication. The schedules contain clear transcription errors (examples cited in "Gotchas"). Confirm intended coordinates against original official records or departmental files before publishing charts.
• Publish official charts and Notices to Mariners alerting users to the Proclamation and the datum to be used. Provide conversion notes where modern datums (if used for other purposes) differ, and provide worked examples to avoid misapplication.

For regulatory agencies and enforcement bodies

• Treat the Proclamation as the legal spatial definition for the territorial sea adjacent to the listed islands, effective 14 February 1983. When enforcing statutes that apply in the territorial sea, determine whether an act occurred within the lines defined by the schedules as implemented on official charts.
• Ensure operational units (maritime police, customs, fisheries inspectors) have up‑to‑date electronic navigational overlays and tables that translate the Proclamation’s lines into coordinates usable onboard ships and shore systems.
• Coordinate between Commonwealth and State agencies. The proclamation refers to "islands … comprised within the State of Queensland" (clause 2). Institutional arrangements between the Commonwealth and the State for delivering services and enforcement in those waters should be reviewed to reflect the declared limits.

For mariners, fishers and commercial operators

• Consult updated official charts that implement the Proclamation. Do not attempt to reconstruct limits from the text unless you are a trained hydrographer using the correct datum and spheroid constants.
• Note that the Proclamation defines the outer limit of the territorial sea; crossing that line may change the regulatory regime that applies (immigration, customs, fisheries, environment). Obtain relevant licences and permissions if activities will occur within the declared territorial sea.
• For navigation, ensure onboard navigation systems are consistent with the datum used in official charts; avoid mixing modern GPS datums without conversion routines.

For surveyors and legal advisors

• Use the Johnston Geodetic Station coordinates and specified spheroid constants when converting or transforming positions for legal evidence, boundary delineation, or drafting licences. Be prepared to explain datum transformations if evidence relies on modern datums that differ from the Australian Geodetic Datum specified in clause 1(2).
• Where coordinates in the Proclamation appear garbled, obtain certified copies of the original Gazette or departmental records and document any corrections or assumptions used to reconcile transcription errors.

For counsel and policy advisers

• Recognise the Proclamation’s legal effect is the fixation of spatial limits under s 7 authority; substantive rights, obligations and penalties that attach to those limits are found in other statutes. When advising clients, cross‑reference the Proclamation’s lines with the specific statutory regimes that will apply in the territorial sea.
• Before advising on litigation or compliance risk, confirm whether subsequent proclamations, corrections or legislative amendments have altered the declared lines or the datum. The instrument itself contains no amendment history in the provided text.

Practical checklist

1. Obtain authoritative source materials (Commonwealth Gazette, original departmental files) to confirm spheroid flattening and to correct typographical errors.
2. Use geodetic software configured to the specified spheroid and Australian Geodetic Datum to compute geodesics and arcs.
3. Rely on official charts updated to reflect this Proclamation when making operational decisions.
4. Coordinate with the relevant Commonwealth/State agencies to identify applicable permits and enforcement regimes for activities within the declared territorial sea.
5. Document any datum transformations used in legal or evidentiary contexts.

Following these steps will align technical and legal practice with the Proclamation’s requirements and address the principal implementation risks visible in the text.