Essential Guide

Weed Control under the Biosecurity Act Post Bushfires

WRITTEN BY Bruce Chalmers

Following the bushfires across much of NSW that had a catastrophic impact on many local government areas, councils and communities are deep into recovery efforts.  As Spring rainfall adds up, one area that may be overlooked is the risks and opportunities that unplanned fire and subsequent favourable conditions can present in relation to weeds.

noxious weeds

Key Instruments

Biosecurity Act 2015 (NSW)
Biosecurity Regulation 2017 (NSW)

Relevant NSW Department of Primary Industry (DPI) policies and procedures:

Biosecurity – Weed Management
Biosecurity Directions
Biosecurity Undertaking
Biosecurity Formal Weed Inspections

The interactions between fire and weeds are complex, varied and often difficult to predict.[1] Depending on the area, unplanned fires can create an opportunity for competitive weed species to colonise and dominate burnt sites.[2]  The movement of equipment, machinery, stock and people associated with fire response and recovery efforts can also facilitate the inadvertent spread of weeds.[3]  However, wildfires can also present local councils and landholders with the chance to undertake opportunistic weed control actions, as the destructive effect of fires can sometimes reduce target weeds and may also facilitate improved access for weed treatment.[4]   Weed management, now regulated under the Biosecurity Act 2015 (NSW) (the Act), is therefore part of the process of restoring fire affected communities.

The Biosecurity Act 2015 (the Act)

The Act establishes a comprehensive framework for the management of pests, diseases and contaminants. It includes the noxious weed control functions carried out by local councils that were previously included in the, now repealed, Noxious Weeds Act 1993 (NW Act).

Although the Act has now been in force for a couple of years, there has only been one Court decision that has considered its scope and then only in a limited way. In Goode v Gwydir Shire Council [2020] NSWLEC 33, the Court held that the Act did not confer any right of private action on members of the public and that only the Secretary can bring proceedings in the Land and Environment Court to remedy or restrain a breach of the Act.[5]

Where is the reference to weeds?

Under the Act priority weeds are no longer defined as ‘noxious’ and the noxious class listings under the repealed NW Act no longer apply. This provides greater flexibly to manage and control all weeds.[6]

The Act is also ‘outcomes focused’ in that its scope is defined with reference to things which may have a ‘biosecurity impact’. A biosecurity impact is an adverse effect on the economy, the environment or the community that arises, or has the potential to arise, from a ‘biosecurity matter’.[7] Importantly, for the regulation of weeds, a biosecurity matter includes the introduction, presence, spread or increase of a pest into or within NSW.

In most cases plants previously categorised as ‘weeds’ are now a ‘pest’ for the purposes of the Act. ‘Pest’ includes a plant, (whether dead or alive) that has, or is suspected of having, an adverse effect on the environment, the economy or the community because it has the potential to, amongst other things:

  1. out-compete other organisms for resources, including food, water, nutrients, habitat and sunlight;
  2. reduce the productivity of agricultural systems or the value of agricultural products;
  3. reduce the amenity or aesthetic value of premises; or
  4. harm or reduce biodiversity.[8]

There is also list of prohibited matters, including weeds, in Schedule 2 to the Act. However, this is not an exhaustive list of the weeds to which the Act applies and any plant which has or is likely to have a biosecurity impact is subject to the Act.

How does the Act regulate weeds?

The Act regulates weeds in three key ways:

  1. by imposing biosecurity duties on persons and occupiers of land to do various things to avoid and manage biosecurity impacts;
  2. regulating specific weeds; and
  3. regulating specific regions or zones.

This Guide focuses on the biosecurity duties imposed by the Act which apply to weeds, for which local councils have a key regulatory role.

Biosecurity duties

The biosecurity duties imposed by the Act include:

  1. a general biosecurity duty;[9]
  2. a duty to notify the presence of a prohibited matter;[10]
  3. a duty to prevent, eliminate or minimise risk posed by a prohibited matter;[11] and
  4. a duty to notify a biosecurity event.[12]

A person who fails to discharge any of their ‘biosecurity duties’ is guilty of an offence under the Act.

In relation to weeds, the general biosecurity duty requires that any person who deals with a weed and knows or ought reasonably to know of the biosecurity risk posed by it has a duty to ensure that the risk is prevented, eliminated or minimised.[13]  The Act contains a very wide definition of ‘dealing’.[14]

An occupier of land is responsible for any weed on that land unless they can establish otherwise. The Act extends this duty to include a requirement that occupiers take steps to prevent, eliminate or minimise any biosecurity risk posed by weeds on public roads, watercourses and other public land in close proximity to the occupier’s land.[15]  Where there is more than one ‘occupier’ of land then each occupier is subject to the same biosecurity duty.[16]  ‘Occupier’ is defined in the Act to include any person having the care, custody or control of the land. The Act does not distinguish between private occupiers of land and land occupied by the Crown or a local council. It is therefore important that councils are aware of their obligations and duties as a land occupier, as well as their duties when acting as the Local Control Authority (LCA) under the Act.

Council functions

In most cases, councils are the LCA for their Local Government Area. As the LCA, a council is responsible for addressing issues relating to weeds in their area, including exercising weed control functions, implementing weed control programs, reporting, and keeping records.[17]  This includes inspecting private and public lands to ensure owners/occupiers of land carry out their obligations under the Act.[18]

Council’s weed control functions are primarily exercised through authorised officers.[19]  Any person appointed as an inspector under the NW Act immediately before its repeal is taken to have been appointed as an authorised officer for the purposes of the Act.[20]

Authorised Officer Functions

Council’s authorised officers may exercise the powers conferred under Part 8 of the Act. These powers are similar to the functions given to investigation officers under the Environmental Planning and Assessment Act 1979 (the EPA Act) and to authorised officers under the Protection of the Environment Operations Act 1997 (the PEO Act). The powers include:

  1. information gathering – officers can require information and records to be furnished, require answers to questions, and demand a person’s name and address;
  2. entering premises – enter onto any premises (note that the consent of the occupier or a search warrant is required for residential premises[21]); and
  3. investigation and risk management functions – these include a range of actions which can be undertaken by the authorised officer, such as conducting examinations, taking samples or erecting signs; however, these must be done in accordance with the purposes and processes specified in the Act.

As the LCA, council’s responsibilities under the Act are limited to weed management and council’s authorised officers can only exercise these powers in relation to weeds located on land (or waterways) for which the Council is the LCA.[22]  Authorised officers cannot exercise these functions in relation to the other matters covered by the Act. DPI has published an Authorised Officers FAQs guide which may assist councils and their staff who are responsible for weed control.


An important function given to an authorised officer is the power to give a ‘biosecurity direction’. Authorised officers can give two different forms of directions:

  1. a general biosecurity direction, which will apply to the public generally or to a specified class of persons; or
  2. an individual biosecurity direction, which applies to a particular person.[23]

A general direction can prohibit, regulate or control (absolutely or conditionally) the carrying out of any activity in connection with weeds, a carrier (meaning anything capable of having a weed on it, attached to it or contained in it) or a potential carrier. A general direction may be given by an authorised officer if the officer reasonably believes the direction is necessary for a purpose identified in section 126 of the Act (e.g to prevent, eliminate or minimise a biosecurity risk or prevent, manage or control a biosecurity impact) and the direction does not exceed the limitations set out in sections 134 to 137.

A biosecurity direction can also be given to a particular person – an ‘individual biosecurity direction’.[24] Examples of what may be included in an individual biosecurity direction are in section 130 of the Act. These include directions requiring the treatment or destruction of a biosecurity matter, such as a weed. Directions should be supported by evidence, such as records of observations or conversations, photographs and reports.

The Act does not expressly require an authorised officer to give advance notice of their intention to issue a biosecurity direction. This is similar to the situation under the PEO Act in respect of notices given under that Act. In that context, the Court has found that, except in urgent or emergency situations, notice is still generally required in order to afford procedural fairness to the intended recipient.[25]  In contrast, the Act expressly states that an authorised officer is not required to notify any person who may be affected by a biosecurity direction before giving the direction.[26]  However, where possible, we recommend that authorised officers’ give notice of their intention to issue a biosecurity direction and provide an opportunity for occupiers to undertake voluntary weed control before a final direction is issued under the Act, to ensure procedural fairness.

DPI has prepared a Biosecurity Directions Procedure, which officers should consult if they are considering giving a biosecurity direction.  This procedure applies to all biosecurity risks and not just weeds. The advice provided within the Procedure is focused on suggesting practices and procedures for risk mitigation.

General Biosecurity Directions

Authorised officers can give a general biosecurity direction by publishing notice of the direction on the DPI website or in the Gazette (or both) or, in an emergency, displaying a copy of the direction in a prominent place in or adjacent to the relevant premises.[27]  While there is an express provision in s.141 providing that notice is not required, DPI guidance states that officers should be proactive in advising persons affected by the general direction.

DPI’s procedure also specifies that a general biosecurity direction can only be given by an authorised officer with the appropriate departmental approval. The following approval is required:

  • NSW DPI, Director level or higher
  • LLS, General Manager level, and
  • LCA, General Manager level.

This appears to be a risk mitigation measure proposed by DPI, as it is not required under the Act.

Individual Biosecurity Direction

Authorised officers may give an individual biosecurity direction by serving the direction in writing to the individual.[28]  Section 392 of the Act sets out how documents are to be served.

A direction may also be given orally (in person), however the oral direction must be confirmed in writing within 7 days after it is given, unless the direction has been complied with by that time.

Similar to provisions under the EPA Act and the PEO Act, an authorised officer may charge an individual a fee for the administrative costs involved in preparing and giving them a biosecurity direction.[29]   Whilst the fee is payable to the Secretary, s.373 of the Act allows a council to exercise any function of the Secretary in relation to the recovery of fees charged in the exercise of functions by a council-appointed authorised officer.

Emergency Functions

The Act also makes provision for authorised officers to exercise particular functions in an emergency. The circumstances in which this power is enlivened is set out in s.122 of the Act. These include where an authorised officer reasonably believes it is necessary to exercise the function because a biosecurity emergency has occurred, is occurring or is imminent, or where they reasonably suspect a biosecurity emergency has occurred, is occurring or is imminent.  In relying on the emergency provisions it would be prudent for officers to document the reasons why they considered the circumstances to be an ‘emergency’.

Weed control notices under the Noxious Weeds Act

Under the repealed NW Act, a council was able to give a ‘weed control notice’ to an owner or occupier of land, requiring the owner or occupier to carry out any of the occupier’s obligations to control noxious weeds. The new Act contains a savings provision which allows any person to continue to apply to the LCA for a certificate as to weed control notices affecting particular land and as to any outstanding expenses payable to the authority or any resulting charge on the land under the repealed Act. If a Council receives such a request, they must issue a certificate addressing these matters.


This guide has provided a brief overview of some of the responsibilities and functions given to local councils under the Act to manage weeds in their local government area.

For further information, or for assistance or advice on enforcement and compliance, please contact the Planning, Environment and Local Government team at BAL Lawyers on (02) 6274 0999.

The content contained in these guides are, of course, general commentary only. They do not constitute legal advice. Readers should contact us and receive our specific advice on the particular situation that concerns them.

Please note that the law detailed in this Essential Guide is correct as at 13 October 2020.

[1] Mark Graham and Kevin Taylor, ‘Fire, Weeds and the Native Vegetation of New South Wales: A report prepared by the Hotspots Fire Project’, March 2018, 10.

[2] Ibid, 14.

[3] Tasmanian Government Department of Primary Industries, Parks, Water and Environment, ‘Managing Weed Spread After Fire’, Invasive Species (online, 28 November 2019) <>

[4] Graham and Taylor, above n 1, 28.

[5] Goode v Gwydir Shire Council [2020] NSWLEC 33 at [74] per Pain J.

[6] Department of Primary Industry, ‘Weed Management Legislation is Changing’.

[7] Biosecurity Act 2015, s 13.

[8] Ibid, s 15.

[9] Ibid, s 22.

[10] Ibid, s 30.

[11] Ibid, s 36.

[12] Ibid, s 38.

[13] Ibid, s 22.

[14] Ibid, s 12.

[15] Ibid, Sch 1.

[16] Ibid, s 20.

[17] Ibid, s 371.

[18] Ibid.

[19] Ibid, s 372.

[20] Ibid, Sch 7[9].

[21] Ibid, s 99.

[22] Ibid, s 372.

[23] Ibid, s 124.

[24] Ibid, s 128.

[25] Liverpool City Council v Cauchi [2005] NSWLEC 675.

[26] Biosecurity Act 2015, s 141.

[27] Ibid, s 127.

[28] Ibid, s 129.

[29] Ibid, s 132.

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