The NSW Government’s Environmental Planning and Assessment (Planning System Reforms) Bill 2025 (Bill) introduces a simple amendment with far-reaching implications for development assessment in NSW: the insertion of the word “significant” before “likely” in section 4.15(1)(b) of the Environmental Planning and Assessment Act 1979 (NSW) (EP&A Act).
This change, which has now passed through both Houses of Parliament and will become law, will narrow the scope of what consent authorities are required to consider when determining a development application (DA), bringing the focus squarely onto impacts that are both likely and environmentally significant.
We view this as a positive and necessary reform that will reduce assessment burden, improve legal certainty, and bring NSW’s planning system in line with risk-based regulatory principles – without compromising environmental safeguards.
The current position: “likely impacts”
Section 4.15(1)(b) of the EP&A Act currently requires consent authorities to consider:
“the likely impacts of that development, including environmental impacts on both the natural and built environments, and social and economic impacts in the locality.”1
The key issue is the breadth of the term “likely”. Courts have historically interpreted it to include impacts that are merely possible or have a real chance of occurring, even if the details are not yet confirmed or the risk of their environmental harm is not material.
This interpretation has resulted in:
- overly broad environmental assessments;
- litigation risk where impacts are said to be overlooked; and
- uncertainty about the scope of the consent authority’s duties.
The reform: a materiality threshold
The Bill proposes that s 4.15(1)(b) be amended to refer to:
“the significant likely impacts of that development…”
This subtle shift will import a materiality threshold, requiring consideration only of impacts that are not just likely, but also significant.
Why this reform makes sense
We support the proposed change for the following reasons:
1. Clarifies and narrows the assessment scope
“Significant likely impacts” introduces a filter for materiality, preventing minor or speculative impacts from derailing or delaying approvals.
2. Reduces litigation risk
Development consents will be less vulnerable to legal challenge over omissions relating to marginal impacts, the consideration of which by the consent authority would not have influenced their decision.
3. Preserves rigorous environmental assessment process
Likely impacts that are genuinely significant will still be captured and addressed through the DA process or through conditions of consent where appropriate.
Execution matters
For the reform to function effectively, clear guidance will be needed on how to identify “significant” impacts in practice. Case law, regulatory guidance, and technical standards will likely play an important role.
In our view, the amendment to s 4.15(1)(b) is a welcome step toward streamlining development assessment while preserving robust environmental protections.
We recommend that proponents, planners and consent authorities begin to anticipate how this reform may shift assessment scope, particularly in large and infrastructure-heavy developments.
For advice on how this change may affect your projects, including DA strategy, EIS preparation or litigation risk, please contact our team of experienced NSW Planning lawyers Kate Swain, Kara Mezinec and Elizabeth Ryan.