State significant development in NSW: declaration, assessment and review

State significant development (SSD) is a Part 4 development-consent pathway. Classification fixes the State assessment process and consent authority; project scope, significant impacts and separate approvals still require analysis. See NSW development approval pathways: a practical map.

The statutory definition is exact:

“For the purposes of this Act, State significant development is development that is declared under this section to be State significant development.” — section 4.36(1) of the Environmental Planning and Assessment Act 1979 (NSW) (EP&A Act)

SSD status depends on a declaration

Section 4.36(2) and section 4.36(3) provide two declaration routes:

1. a State environmental planning policy may declare any development, or any class or description of development, to be SSD; or
2. the Minister may, by a Ministerial planning order, declare specified development on specified land to be SSD.

Classification usually begins with the schedules and thresholds in the State Environmental Planning Policy (Planning Systems) 2021 (the Planning Systems SEPP). Apply the defined development type, location, estimated development cost and the aggregation rule in section 2.6 to the complete proposal. Most thresholds are expressed as an estimated development cost; a few identified sites still use capital investment value. The thresholds change often, so apply the version that governs the application.

For an individual Ministerial order, section 4.36(3A) requires publicly available advice from the Independent Planning Commission (IPC) about State or regional planning significance. Development that includes residential accommodation is excepted: section 4.36(3B). After an order is made, the Planning Secretary must notify the relevant council: section 4.36(3C).

A Government Bill would widen that exception. The Energy Legislation Amendment (Prioritising Renewable Energy) Bill 2026 (NSW) would let the Energy Minister declare “priority energy projects”. A Ministerial order declaring one of them to be SSD would then not need IPC advice, and the Bill would confirm that the Minister may direct the IPC about SSD. The Bill passed the Legislative Assembly on 28 May 2026 and, at 30 September 2026, was still before the Legislative Council. It is not law unless it is passed and commenced.

The Housing Delivery Authority, a statutory body since 15 December 2025, advises the Minister on request, including about declaring particular residential development to be SSD: section 2.11C of the EP&A Act. It works under a published process. Its recommendation neither grants consent nor makes it the SSD consent authority.

The Act and SEPP allocate the consent authority

Section 4.5(a) makes the Minister the consent authority unless an environmental planning instrument declares the IPC for development of that kind. The operative declaration is section 2.7 of the Planning Systems SEPP. Subject to its exceptions, the IPC determines an application for State significant development where:

• the council of the area has duly made a submission by way of objection under the mandatory community-participation requirements in Schedule 1 to the EP&A Act;
• at least 50 submissions by way of objection, other than from a council, have duly been made under those requirements; or
• the applicant has disclosed a reportable political donation under section 10.4 of the EP&A Act in connection with the application.

Those triggers do not apply to an application made by or on behalf of a public authority, or to development the Minister has declared to be State significant infrastructure related development under section 2.7(2). Separately, the IPC is the consent authority for State significant development on which the Minister has asked it, in writing, to hold a public hearing under section 2.9(1)(d) of the EP&A Act: section 2.7(3A), inserted on 9 September 2026.

None of section 2.7, including that public-hearing rule, applies to development declared SSD by a Ministerial order under section 4.36(3) of the Act: section 2.12(2), in force since 18 August 2026.

The objection triggers now differ by class of development:

• For mining, petroleum and extractive industry projects, metal and mineral processing works within Schedule 1, section 9(a), data centres, and electricity generating works using gas, coal, solar or wind power, a council objection is not a trigger, and the objection threshold is at least 100 submissions rather than 50.
• Stand-alone battery energy storage systems reach the IPC only through a political donation disclosure or a public hearing request.
• Neither objection trigger applies to in-fill affordable housing, build-to-rent housing, seniors housing, or development on the identified sites listed in Schedule 2 to the Planning Systems SEPP, which include the accelerated transport-oriented development precincts.

These carve-outs were made by amendments in 2025 and 2026, most recently in August and September 2026, so check the version of section 2.7 that applies to the application, and any transitional provision, against its lodgement and exhibition dates.

For the objection thresholds, section 2.7(6) counts a petition as one submission, and submissions containing the same or substantially the same text as one. Apply the criteria to the current application record rather than inferring them from project scale.

A further change starts on 1 November 2026. From then, an objection counts toward the 50 or 100 thresholds only if it is made by a person who resides in New South Wales, owns land in New South Wales or has a place of business in New South Wales, and objections from a council still do not count. The change does not apply to a development application or modification application lodged before 1 November 2026: State Environmental Planning Policy (Planning Systems) Amendment (Independent Planning Commission) 2026, Schedule 1, items 1, 3, 4 and 8.

The Department of Planning, Housing and Infrastructure (DPHI) administers the assessment and prepares the report. That role does not make it the consent authority.

Assessment begins with project-specific requirements

1. Scoping fixes the assessment task

Before preparing an environmental impact statement (EIS), section 173 of the Environmental Planning and Assessment Regulation 2021 requires the responsible person to apply for the Planning Secretary’s environmental assessment requirements (SEARs), unless waived under that section. Section 175 addresses SSD involving a gateway certificate; section 176 governs notice. Section 174 was repealed on 1 July 2026.

Scoping should identify the whole project, connected infrastructure, alternatives, specialist studies, consultation and other approvals. SEARs are project-specific minimum requirements; the Act, Regulation and applicable guidelines remain controlling.

For SSD, the application for SEARs must have regard to the State Significant Development Guidelines: section 173(3). The Department has updated those guidelines for the 2025 reforms, but its guidelines page, last updated on 2 April 2026, says the guidance on preparing a scoping report has not yet been updated and will be “in the coming months”. That notice was still there on 30 September 2026. Check the current version before preparing a scoping report.

2. The application must be accompanied by an EIS

Section 4.12(8) of the EP&A Act requires an SSD application to be accompanied by an EIS. Regulation sections 191, 192 and 193 address compliance, content and ecologically sustainable development.

The EIS should provide a stable project description and a traceable avoidance, mitigation and residual-impact case. Specialist appendices must align on footprint, construction, staging and operating assumptions.

3. Exhibition places the project evidence on the public record

The application and EIS are publicly exhibited under the community-participation requirements in Schedule 1 to the EP&A Act. Submissions may come from councils, agencies, landholders, community groups and the public. Section 59 of the Regulation provides for submissions to be supplied to the applicant, a response where required and publication of core project documents.

4. Responses and amendments must remain traceable

The applicant’s response should map every material issue to evidence, a project change, proposed mitigation or a reasoned position. A material amendment may require further public participation or assessment.

DPHI then prepares its assessment report. The consent authority determines the application under section 4.38, having regard to the relevant section 4.15 matters. Since 15 December 2025, section 4.15(1)(b) refers to the significant likely impacts of the development, with section 4.15(1A) and section 4.15(1B) further structuring the assessment.

A pending-application saving may preserve the former assessment text. Under Schedule 6, section 34(2) of the Regulation, a relevant application lodged, but not finally determined, before the amendments commenced “must be determined as if the items had not commenced”. A relevant application includes a development application and an application to modify a consent: section 34(6). The saving “ceases to have effect 12 months after” the amendments commenced on 15 December 2025: section 34(3). The application dates select the current or saved assessment text.

The 90-day prescribed assessment period in section 91 of the Regulation is not a promised determination deadline. Its commencement and calculation depend on section 92, section 93, section 94, amendments and the actual application record. Expiry may enliven the applicant appeal mechanism in section 8.11, subject to the current exclusions. See Deemed refusal in NSW: when appeal rights arise.

Connected infrastructure requires a project-boundary decision

Separating a project into consent and non-consent components does not make connected effects disappear. Section 4.38(4) deals with a single proposed SSD where one part would otherwise be carried out without consent.

The current Act also gives the Planning Secretary an express classification function. Section 4.38(4A) says: “The Planning Secretary may determine that particular development does or does not form part of a single proposed development for the purposes of subsection (4).”

Section 4.38(4B) provides: “Subsection (4) does not apply to development that the Planning Secretary determines does not form part of a single proposed development under subsection (4A).”

Section 4.38(4C) says the regulations “may provide for” the form and way of making a determination, the procedure “including requirements for consultation”, and the circumstances in which the Planning Secretary may make one.

Subsections (4A) to (4C) were inserted on 2 December 2024 by the Environmental Planning and Assessment Amendment (State Significant Development) Act 2024 (NSW), which its long title describes as made “in response to a recent court decision impacting State significant development consents”. The same Act validated anything done before that date that would have been valid but for section 4.38(4). The validation does not extend to a development consent that a court had already declared invalid, or to a development application lodged in reliance on such a consent: Schedule 8, Part 6 to the EP&A Act.

That classification machinery is distinct from the question of which impacts are mandatory considerations under the current section 4.15(1)(b). On that second question the Regulation now speaks directly. Section 65A of the EP&A Regulation, made under section 4.15(1A)(b) and in force since 15 December 2025, declares that the significant likely impacts of “other development” (development that is likely to be, or will be, required to be carried out as a result of the development the subject of the application but is not included in it) are not relevant factors when the consent authority considers the significant likely impacts of the development under section 4.15(1)(b). The Department’s practice note on section 4.15 gives the example of a transmission line needed to power a mine that is to be assessed separately under Part 5.

The practice note also states that section 65A does not prevent a deferred-commencement or other condition requiring the connected approval to be obtained before the consent operates. It adds that the impacts of other development may still be relevant under other heads of consideration, such as the provisions of an environmental planning instrument or the public interest. Whether section 65A governs a particular application depends on the lodgement date and the Schedule 6 savings discussed above.

In Bingman Catchment Landcare Group Incorporated v Bowdens Silver Pty Ltd [2024] NSWCA 205, the NSW Court of Appeal allowed an appeal from the dismissal of Class 4 judicial-review proceedings. White JA, with Adamson JA agreeing, said at [24]:

“the respondent could not exclude the IPC’s consideration of the off-site impacts of the mine by excluding information as to the likely or possible routes of a transmission line from its development application.”

The majority held that whether an impact was “likely” was an evaluative matter for the consent authority, found that the IPC had not considered the transmission line (as the respondent had admitted), and upheld the grounds of appeal based on that failure: [99]–[106], [109], [118]–[119]. Price AJA dissented from the orders: [120]–[135]. The appeal was allowed and the mine consent declared void and of no effect.

The transmission line was necessary to that mine, and the decision construed the former words “likely impacts” in section 4.15(1)(b). For an application lodged on or after 15 December 2025, and, once the 12-month saving in Schedule 6, section 34(3) expires, for any application still undetermined, two changes must be read together: section 4.15(1)(b) now refers to “significant likely impacts”, and section 65A of the Regulation removes the significant likely impacts of “other development” not included in the application from the section 4.15(1)(b) assessment. On facts like Bingman, that combination would be expected to alter the analysis under section 4.15(1)(b) for a later application, although connected works may still bear on the Planning Secretary’s single-proposed-development determination under section 4.38(4A), on the public interest and on any applicable planning policy. Apply the text that governs the lodgement date; the connected-effects principle is no longer a free-standing rule under section 4.15(1)(b).

The approvals strategy should therefore identify:

• every enabling and connected work;
• whether it forms part of a single proposed SSD;
• effects of infrastructure proposed for a later application;
• the legal pathway for each component; and
• the evidence available to assess cumulative and indirect effects.

SSD does not displace biodiversity and other approvals

Current section 7.9(2) of the Biodiversity Conservation Act 2016 (NSW) states the biodiversity development assessment report (BDAR) requirement: “Any such application is to be accompanied by a biodiversity development assessment report unless the Planning Agency Head determines that the proposed development is not likely to have any significant impact on biodiversity values.” The former joint Planning Agency Head and Environment Agency Head test ceased on 1 July 2026, when Schedule 3.1, item 1 of the Environmental Planning and Assessment Amendment (Planning System Reforms) Act 2025 (NSW) commenced. A development application, or an application to modify a consent, lodged but not finally determined before that date is determined as if the amendment had not commenced: Schedule 6, section 46 of the Regulation. See Biodiversity offsets scheme triggers.

Section 4.41 and section 4.42 identify approvals that are unnecessary for approved SSD and those that must be substantially consistent with the consent. They are a closed scheme, not a general “one approval” rule. Land access, Commonwealth approval and approvals outside those sections may remain.

The question under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (Cth) (EPBC Act) must be assessed independently. See Commonwealth environmental referrals and our project approvals and licensing practice.

Review rights turn on the decision-maker and procedure

Review rights depend on the decision-maker and procedure:

• an IPC decision made after its public hearing has no applicant or objector merits appeal under section 8.6(3);
• other SSD applicant appeal rights require the current Part 8 provisions, exclusions and deadlines to be checked;
• objector merits rights are confined and do not arise for every SSD; and
• judicial review tests legal validity, not whether the Court prefers a different planning outcome.

Denman Aberdeen Muswellbrook Scone Healthy Environment Group Inc v MACH Energy Australia Pty Ltd [2025] NSWCA 163 was an appeal from the dismissal of Class 4 judicial-review proceedings concerning an IPC approval for a particular coal-mine extension. Ward P said at [109] (Adamson JA agreeing in the orders and substantially in her Honour’s reasons, while giving separate reasons; Price AJA agreeing with both judgments at [245]):

“the Commission failed to engage with the essential matter with which s 4.15(1)(b) is centrally concerned – the impacts of the proposed development on the locality of the development.”

The Court allowed the appeal and, subject to remittal on possible conditional-validation orders, declared the consent invalid for failure to consider a mandatory consideration. Its reasoning concerned the accepted causal chain from the project’s Scope 3 emissions to climate-change impacts in the locality, on the evidence and reasons before the IPC. It does not establish that approval must be refused whenever Scope 3 emissions arise. The Court also construed the former wording of section 4.15(1)(b), before “significant”, section 4.15(1A) and section 4.15(1B) were inserted.

The High Court granted MACH Energy special leave to appeal on 4 December 2025 (MACH Energy Australia Pty Ltd v Denman Aberdeen Muswellbrook Scone Healthy Environment Group Inc [2025] HCADisp 297) and heard the appeal, case S174/2025, on 13 May 2026. At 30 September 2026 no judgment had been published, and the matter remained listed as a current case. The Court of Appeal decision is operative, but its detailed reasoning is under appeal; check the official High Court case page before relying on it.

A single controls matrix exposes omissions

Maintain one live matrix from scoping to determination:

Topic	Declaration or legal source	Evidence	Connected approval	Decision risk
SSD classification	SEPP schedule/order	Threshold calculation		Wrong pathway
Project description	Application/EIS	Consolidated plans	Connected works	Fragmentation
Significant impacts	s 4.15, reg s 65A and SEARs	Specialist studies	Agency/EPBC	Missing or excluded consideration
Biodiversity	Biodiversity Conservation Act 2016 (NSW) / SEARs	BDAR	Credits/approval	Unresolved residual
Conditions	s 4.17	Mitigation commitments	Later plans	Uncertain delivery

The matrix makes the assessment auditable and exposes an omitted component before it becomes a validity issue.