Biodiversity Values in NSW. What the BC Act 2016 mapping does to your lot.

In May 2024 the NSW Government consolidated several separate biodiversity-related mapping layers into a single authoritative dataset published by Local Land Services and Biodiversity Conservation Science (the BCS division of DCCEEW). It is called the Biodiversity Values Map. The 2025 and 2026 updates extended its coverage.

If your NSW lot sits inside the Biodiversity Values Map and you intend to develop, you have a specific obligation under the Biodiversity Conservation Act 2016 that most buyers do not know exists until the DA assessor flags it. This post explains what the layer maps, what it triggers, and what it typically costs.

What the map covers

The Biodiversity Values Map consolidates land that contains:

• High-quality core habitat for threatened species
• State Environmental Planning Policy (Vegetation) areas of value
• Land subject to Biodiversity Stewardship Agreements (where private owners have agreed to long-term protection in exchange for biobanking credits)
• Critical habitat declared under the BC Act
• Areas of Outstanding Biodiversity Value (AOBV)

The total mapped area is around 1.2 million hectares as of 2026, or roughly 1.5% of NSW's land area, concentrated in coastal regions, on the western fringes of the Greater Sydney basin, in parts of the Hunter, and across the Northern Rivers.

Critically, the map is updated. A lot that is not mapped today can be mapped next year if a threatened species record is added or if neighbouring habitat extends across the boundary. Owners are notified by mail when their lot is added.

What being on the map triggers

If your lot is on the Biodiversity Values Map AND you propose development that involves clearing native vegetation OR ground disturbance over 0.5 hectares (or 1.0 hectare in some metropolitan local government areas), the development application requires a Biodiversity Development Assessment Report (BDAR) prepared by an Accredited Assessor.

A BDAR is a specific document that:

1. Maps the vegetation on the site
2. Identifies the threatened species and ecological communities present
3. Calculates the biodiversity impact under the Biodiversity Assessment Method (BAM)
4. Quantifies the biodiversity credits the developer must retire to offset the impact
5. Sets out the avoidance, minimisation and offset measures

The cost

For a typical small residential subdivision or substantial single-dwelling DA on a mapped lot, the BDAR itself runs $8,000 to $25,000 depending on:

• The site area (more area = more vegetation survey work)
• The threatened species present (some species require multi-season survey work, extending the timeline)
• The biodiversity credit class and price (some credits are common and cheap, others are scarce and expensive)

The credit retirement is a separate cost, often substantially larger. A clearance involving 0.5 hectares of high-conservation-value vegetation can require credit retirement worth $40,000 to $200,000 depending on the species and ecosystem class.

For larger commercial or industrial projects, the BDAR plus credit retirement can run into the millions.

What you cannot do

Two things are explicitly off the table on mapped land:

1. Clear-and-rebuild without a BDAR. The simple "knock the existing dwelling down and replace it" pathway is not available on biodiversity-mapped land if the build involves expanding the footprint into vegetated areas.
2. Avoid the BDAR by waiting. Some buyers assume that not developing the lot is enough. It is, but the lot's resale liquidity is constrained because the next buyer faces the same BDAR requirement.

What you can do

Three pathways:

1. Build within the existing footprint. If the new dwelling sits inside the existing cleared area and does not extend into mapped vegetation, the BDAR may not be triggered. This is the most common practical strategy.
2. Apply for a Biodiversity Stewardship Agreement. If your lot has high biodiversity value but you do not need to develop it, you can register a Stewardship Agreement, earn biodiversity credits, and sell them to developers who need to retire credits. The market price varies but credits in scarce classes sell for $20,000-150,000 per credit.
3. Pursue the Like-for-Like Variation Rule. Where biodiversity offsets are not available in the same vegetation class, the Like-for-Like Variation Rule allows substitution. This is technical and requires the Accredited Assessor to argue the case, but it can reduce credit cost by 40-60%.

How to read the map

Three free sources:

• The Biodiversity Values Map portal at the Department of Climate Change, Energy, the Environment and Water site. Type the address, see the polygon.
• The Biodiversity Conservation Science portal publishes the raw map data plus threatened species records overlaid.
• The Local Land Services portal has the consolidated layer used in most council assessments.

The map shows you the polygon. The polygon tells you the lot is or is not affected. What it does not tell you is the specific biodiversity values present on the lot. That requires either reading the threatened species register OR commissioning a site assessment.

For lots that are mapped, the report flags the BDAR requirement and notes the typical BDAR cost range. For lots that are not mapped today, the report notes the proximity to mapped land, which is the leading indicator of future inclusion.

Biodiversity is the layer most NSW buyers do not check and most NSW DAs surface late. Checking it early is one of the highest-leverage moves in pre-purchase due diligence for any rural-fringe or peri-urban lot.