Assessment of significance

An assessment of significance is an analysis of the impacts a proposed development or activity is likely to have on threatened species, populations, ecological communities or habitat.

An assessment of significance under the Environmental Planning and Assessment Act 1979 (EP&A Act) is the first step in considering potential impacts.

For developments likely to affect threatened species, populations, ecological communities or their habitats, a species impact statement is also needed. This is outlined in the Threatened Species Conservation Act 1995 (TSC Act).

Both the assessment and the statements must be prepared:

  • according to the relevant legislation
  • by a project applicant or a qualified consultant working on the applicant’s behalf.

The assessment process

The assessment considers a number of factors that are looked at together to determine how likely it is that a development will have a significant impact on biodviersity.


The Threatened Species Assessment Guidelines: the assessment of significance provide more information about the process and requirements.

Section 91 licences

A section 91 licence is needed for actions that are likely to harm a threatened species, population or ecological community. This licence is also needed for actions that damage the habitat of a threatened species, population, or ecological community, including habitat critical to the survival of endangered species (critical habitat).

For information about how a section 91 licence is assessed, including the time this is likely to take, read applying for a section 91 licence.

Legal requirements

For more information about the legal requirements for an assessment of significance, see section 5A of the EP&A Act or section 94 of the TSC Act.

Species impact statement

A species impact statement is needed:

  • if the assessment of significance finds the development likely to affect threatened species, populations, ecological communities or their habitats
  • if there is reasonable doubt about the likely impacts of a development, or where detailed information is not available.

A species impact statement can be presented by itself or included in an environmental impact statement.

A species impact statement must:

  • describe the nature, extent, location, timing and layout of the proposed action or development
  • describe and assess the threatened species, populations or ecological communities known or likely to be found in the area affected by the activity – this should include habitat requirements, conservation status, estimates of abundance, key threatening processes, and whether there are available threat abatement or recovery plans
  • describe the location, type, size and condition of the habitats (including critical habitat) of threatened species, populations and ecological communities – this should include details of the distribution and condition of similar habitats in the area likely to be affected
  • present feasible alternatives to the development or action that are likely to have a lower impact, outlining reasons for these alternative actions
  • list approvals necessary under any other act or law before the action may be lawfully carried out, including existing approvals
  • state the detailed qualifications and experience in threatened species conservation of the people involved in preparing the species impact statement.

Legal requirements

For more information about the legal requirements of a species impact statement, see section 110 of the TSC Act.