There are approximately 180,000 kilometres of public roads in NSW. Coupled with rail and other linear reserves, it is estimated that the linear reserve network covers about 6% of NSW.

The vegetation alongside roadsides and other linear infrastructure form critical habitat corridors across often fragmented landscapes and contain native species and habitat resources (such as hollows) that are rare in the surrounding landscape.   Biodiversity is the variety of life forms, including flora and fauna, the genes they contain and the ecosystems in which they live.

Transport for NSW works in partnership with other landowners, regulators and experts to minimise the impact of its infrastructure development program to biodiversity through sound evidence-based policy and guidance.

Transport aims to:

  • avoid and minimise impacts first
  • mitigate impacts where avoidance is not possible
  • offset where residual impacts cannot be avoided

The research and management studies for individual projects can be found in our Projects section.

Biodiversity guidelines: Protecting and managing biodiversity on projects

Transport has developed best practice guidelines for project managers, staff and contractors to use to help protect biodiversity during construction of road projects and ongoing maintenance works.

The guidelines provide a comprehensive range of measures to minimise the impact to flora and fauna, prior to and during the clearing of native vegetation and their habitats. The guidelines include protocols for the:

  • protection of surrounding areas excluded from clearing
  • staged removal of vegetation and habitat trees
  • handling of fauna found during clearing
  • weed and pathogen management
  • re-use of vegetation and removal of other habitat features such as bushrock
  • provision of supplementary fauna habitat such as nest boxes and
  • re-establishment of native vegetation

Microbat management guidelines

Transport for NSW has also prepared microbat management guidelines to assist Transport staff undertaking works in culverts, bridges and other structures. These guidelines target the three species of bats most commonly found in Transport structures being Southern Myotis (Myotis macropus), Large bent-winged Bat (Miniopterus orianae oceanensis) and the Little Bent-winged Bat (Miniopterus australis).  

Koala protection and management

Transport for NSW, in partnership with the Department of Planning and Environment, is looking at ways to reduce the impact of the existing infrastructure network on koalas as part of the NSW Koala Strategy. These works are in addition to koala protection actions routinely undertaken for all new infrastructure development projects such as road duplications and widening projects.

The first Transport vehicle strike hotspot addressed was Picton Road in Wollondilly Shire. Fencing has been installed addressing two known koala vehicle hotspots by channelling koalas towards existing crossings under the road. Koalas have been observed using the crossings and no koala vehicles strike has been observed since the fencing was completed in 2019.

The second vehicle strike hotspot being investigated is on Heathcote Road at Deadman’s Creek on the border between Liverpool and Sutherland Local Government Areas. This area is in close proximity to the Heathcote Road bridge project. Community reports and DPE fauna databases indicate that this location is a worsening area for koala vehicle strike.

Transport has commissioned an Options Report to examine the options available to reduce vehicle strike at this location in consultation with the Department of Defence and the Department of Planning and Environment (DPE). This report recommends underbridge improvements to Deadman’s Creek Bridge to facilitate koala passage under the bridge and exclusion fencing on both sides of Heathcote Road to funnel koalas to the bridge and minimise koala access to Heathcote Road. DPE and TfNSW have entered a funding agreement to complete these works.  Construction of the first stage, being the underbridge improvements to Deadman’s Creek bridge, is expected to commence Nov 2022.  The second stage of the works, involving the installation of koala exclusion fencing, is currently in planning phase. TfNSW will also continue to work with Department of Defence in relation to security fencing installed along the boundary of the Defence lands.

For more information about the NSW Koala Strategy see NSW Koala Strategy on the NSW Department of Planning and Environment website.

For a leading example of how Transport mitigates impacts to koalas as part of its infrastructure development program see the Woolgoolga to Ballina project pages.

Biodiversity offsetting

Transport for NSW seeks to avoid, minimise and mitigate the impacts of roads and other infrastructure on biodiversity during the development and design of its projects. Where impacts cannot be avoided or mitigated, Transport participates in the NSW Biodiversity Offset Scheme.

The Biodiversity Offset Scheme is a market based biodiversity offsetting scheme administered by the NSW Department of Planning and Environment (DPE). It provides:

  • a consistent biodiversity assessment process for development based on the principle of no net loss
  • a rigorous and credible offsetting scheme
  • an opportunity for rural property owners to generate income by managing land for conservation

Under the Biodiversity Offset Scheme property owners enter a Biodiversity Stewardship Agreement with the NSW Minister for the Environment and can then sell the biodiversity credits generated by their properties. More information about the scheme can be found on the Biodiversity Conservation Trust.

Case study examples of biodiversity stewardship and Biobanking agreements sponsored by Transport including agreements over Transport-owned land can be found in the Biodiversity offsets case studies, March 2022.

Meeting biodiversity offset requirements for approved projects

Transport participates in the Biodiversity Offset Scheme where required by the NSW Biodiversity Conservation Act 2016 (NSW) and provides aquatic offsets where required by the NSW Department of Primary Industry guidelines. This includes the far majority of State Significant Infrastructure (SSI) projects. Some projects also require biodiversity offsets under Environment Protection and Biodiversity Conservation Act 1999 (Cth) (EPBC Act).

In addition, Transport voluntarily provides offsets for impacts below the legislative thresholds for smaller projects authorised by Transport under Part 5 Division 5.1 of the Environmental Planning and Assessment Act 1979 (NSW) in recognition of the cumulative impacts many small projects can have on biodiversity.

The Biodiversity offsets progress report shows Transport's progress towards meeting its offset requirements for projects that have triggered the Biodiversity Offset Scheme. Additional information can be found on the Transport project pages and on DPE's planning portal.

Transport for NSW future biodiversity credit demand

Transport starts planning for biodiversity early in the infrastructure development process. Our primary aim is to avoid impacts on biodiversity where-ever possible and so understanding what biodiversity values are likely to be present is an important part of the planning process. This work can be done many years in advance of seeking approval for a project.

One of the outcomes of this work are estimates of the type and number of biodiversity credits that Transport may be interested in purchasing in the future, subject to final route selection including design refinements to avoid impacts, and obtaining final planning approval and other authorisations. These estimates comprise potentially market sensitive information that should be shared with the market as early as possible. Consequently, Transport maintains a register of our likely strategic biodiversity credit demand to assist landholders who may be interested in generating biodiversity credits.

Transport's primary aim is to avoid impacts on biodiversity where-ever possible, so entries to this register can change as route planning processes progress. Timeframes for credit purchase cannot be reliably estimated and may be within the 5-15yrs from listing on this register. Listing of a credit in this register, however, does not guarantee that Transport will be in the market for that credit at any time in the future.

Once we are ready to participate in the market, Transport will contact potential sellers listed on Biodiversity Offsets Scheme public registers | NSW Environment, Energy and Science and, in some cases, will conduct public ‘expression of interest’ processes. For more information on how we purchase credits see our Selling biodiversity credits to Transport factsheet.

Roadside Environment Committee

The NSW Government established the NSW Roadside Environment Committee (REC) in 1994 to promote and coordinate leading practice in linear reserve environmental management across NSW.

Biodiversity research

Transport for NSW funds research into measures that may minimise the impact of roads on biodiversity. Biodiversity research assists planning, design, construction and maintenance of the road network.

Transport has funded research on:

  • the design and effectiveness of fauna underpasses and overpasses
  • impact of roads (construction and operation) on koalas
  • threatened microbats on bridges
  • the design of transparent noise walls to minimise bird strike
  • the impact of bridge construction and operation on mangrove and estuarine saltmarsh habitats
  • research on scent deterrents in the management of vehicle and fauna collisions
  • Green and Golden Bell Frog population monitoring
  • threatened bird, reptile and fish responses to road construction
  • translocation of threatened species and rehabilitation of key habitat (Purple Copper Butterfly – Paralucia spinifera)
  • offsetting biodiversity impacts
  • promoting native fish passage through culverts
  • use of nest boxes by native fauna

Code of Practice for minor works in NSW waterways

The former Roads and Maritime in cooperation with the Department of Primary Industries (NSW Fisheries) have prepared a Code of Practice for Minor Works in NSW Waterways. The Code simplifies the statutory consultation process required under the Fisheries Management Act for certain dredging and reclamation actions that have been considered by both agencies to be of low risk to native fish and key fish habitats.

The Code:

  • defines and identifies those dredging and reclamation works which can be undertaken without consultation with NSW Fisheries and those works are not covered by the Code and will continue to require ongoing consultation with NSW Fisheries in accordance with the Fisheries Management Act
  • specifies the safeguards that must be used for all minor dredging and reclamation works including adherence to the Roads and Maritime Environmental Procedure for Routine and Minor works
  • states the timeframes for which the Code is intended to apply

Vegetation clearing best practice

Vegetation clearing is a critical environmental compliance risk for Transport for NSW during road construction and maintenance activities. Transport has produced an awareness video for staff and contractors on vegetation clearing best practice.


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Microbat Management Guidelines

A guide for undertaking works in culverts, bridges and other structures. December 2021.



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