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

These linear reserves and undeveloped land for new road construction contain important biodiversity that is 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.

Roads and Maritime Services works in partnership with other landowners, regulators and experts to minimise the impact of its activities to biodiversity through sound evidence-based policy and guidance.

When managing biodiversity, Roads and Maritime 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.

Codes of Practice

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.

Our biodiversity guidelines

Roads and Maritime have 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

    Biodiversity offsetting

    A biodiversity offset is an action taken by Roads and Maritime to account for the residual impacts on biodiversity from an infrastructure project after all effort has been made to avoid and minimise impacts through both careful route selection processes and the implementation of biodiversity impact mitigation measures.

    Offsets are areas of land that are protected and managed to improve biodiversity values. Roads and Maritime prepare Biodiversity Offset Strategies for projects that require offsets after effort has been made to avoid and minimize impacts on biodiversity. These strategies identify the amount, type and location of the offset needed to compensate for the residual impacts to biodiversity.

    Biodiversity offsets maybe required in the following circumstances:

    1. As a condition of approval or concurrence under the NSW Planning and Assessment Act 1979 (or the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) or as
    2. Part of a licence requirement under the Threatened Species Conservation Act 1995 (TSC Act) or the Fisheries Management Act 1994 (FM Act).

    Roads and Maritime biodiversity offset mapping by region

    Roads and Maritime regions: A map showing the location of the Roads and Maritime regions.

    WesternSouth WestSouthernSydneyHunterNorthern

    Biodiversity research

    Roads and Maritime Services 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.

    Roads and Maritime 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.

    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 the State. Find out more about the Roadside Environment Committee.


    Roads and Maritime biodiversity guidelines

    Code of Practice for Minor Works in NSW Waterways

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