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Development and Assessment

State Significant Infrastructure

The size, economic value or potential impacts that certain infrastructure has can give it State significance.

State significant infrastructure

Under the Environmental Planning and Assessment Act 1979 (EP&A Act), some infrastructure projects can be declared as State significant infrastructure (SSI) if they are important to the State for economic, environmental or social reasons.

Infrastructure that is State significant are identified in Section 3 and 4 of the State Environmental Planning Policy (SEPP) as:

  • rail infrastructure
  • road infrastructure
  • port, wharves and boating facilities
  • water storage and treatment plants
  • pipelines
  • certain national parks development.

The above infrastructure types are considered State significant if it is above a certain size or capital investment value or is in a sensitive environmental location.

Certain SSI projects can be declared as critical State significant infrastructure (CSSI) if they are determined as essential to the State by the Minister for Planning.

Some examples of CSSI are:

  • Pacific Highway Upgrade
  • WestConnex
  • Snowy 2.0
  • Sydney Metro Rail.

The Declaration of SSI and CSSI (2021) guide sets out the general principles and key reasons for the Minister to declare development as SSI or CSSI.

Who determines State significant infrastructure applications?

SSI and CSSI projects are assessed under Division 5.2 of the EP&A Act and require the approval of the Minister for Planning before they may proceed.

The department coordinates the assessment of all SSI projects under the EP&A Act which involves carrying out all relevant administrative functions, coordinating inputs from State and Commonwealth agencies and working closely with councils to ensure local and regional issues are fully considered.

The Department then prepares a detailed whole-of-government assessment report on the merits of SSI projects for the approval authority.

Community involvement is essential to the process and all SSI environmental impact statements (EIS) are exhibited for at least 28 days.

State Significant Infrastructure Guidelines

The State Significant Infrastructure Guidelines provide a detailed explanation of the SSI process and set out clear expectations about the quality of environmental assessment documentation.

The EP&A Regulation requires certain SSI documents, including EISs, amendment applications and modification requests to be prepared having regard to the State Significant Infrastructure Guidelines.

For further information on the guidelines visit the NSW planning website

SSI Projects 

Find out more about how projects are classified as SSI or CSSI and the different types of SSI projects

Read more

SSI Process

Find out more about how the merits of SSI projects are assessed before a final decision is made.

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SSI Modifications

Find out more about how SSI approvals can be modified

Read more
Last updated: 25/08/2023