> Fire management > Managing bushfire risk

Fighting fire with fire

Globally, fire managers are being challenged to keep pace with a rapidly changing climate which brings with it more frequent and intense bushfires. In South Australia, the driest state in the driest inhabited continent on earth, this comes with significant challenges. These include but are not limited to managing public safety with an increase in population in high-risk areas, and the potential for bushfires to become larger, more complex, and increasingly difficult to contain.

To help manage this risk NPWS fire managers use prescribed burning to reduce bushfire fuel along with other important strategies such as fire access tracks, mechanical fuel breaks, and slashing.

The prescribed burn program exposes NPWS crews to fire in different terrain and fuel types. They develop practical experience in assessing fuel loads, reading fire behaviour and learning different lighting techniques.The experience and technical knowledge learned through the more controlled environments of prescribed burns is critical when crews respond to bushfires and plan and implement tactics such as backburning.

The NPWS prescribed burn program is underpinned by fire management plans which identify bushfire risk and guide fire management activities on parks and Crown Land, to better reduce the risk and impact of catastrophic bushfires. These plans are developed alongside State Bushfire Coordination Committee Bushfire Management Area Plans, which identify bushfire risk across all land tenures, including private land.

Statewide strategic planning considers local issues and assets (life, property and the environment) as well as the potential impact of large landscape scale bushfires. Fire management plans set a long-term vision and are designed to be flexible and responsive. This allows for updates as bushfire risks evolve, or new information becomes available. Regional staff continually assess the plans in the context of the local landscape and implement a dynamic program of prescribed burns on public and private land, along with other activities to manage bushfire risk.

If a bushfire does occur, CFS Incident Management Teams (IMT) are made aware of where bushfire fuel has previously been reduced with prescribed burns and other activities from these strategic plans, which helps them develop tactical action plans during a bushfire.

NPWS uses the best available science, data and knowledge from around the country to run its fire management program. This information guides management plans and informs activities to help reduce the risk of bushfires and manage the environment.

Every prescribed burn is an opportunity to build on knowledge and learn more about fire ecology and fire behaviour. Post prescribed burn (and post bushfire) monitoring, annual auditing, reporting and recording outcomes informs future activities in the continual evolution of the program.

Flexibility is key as NPWS leverages off old bushfire and prescribed burn sites to build a mosaic of vegetation age classes in the landscape to provide fuel breaks and where possible benefit local native plants and animals.

Reduces bushfire risk

Bushfires will never be eliminated from the environment and prescribed burns won’t stop all bushfires, but they are designed to limit the spread and impact and make them easier and safer to suppress. The primary purpose of prescribed burning is to reduce fuel loads in the landscape so bushfires have less fuel to burn.

Here’s how it works:

Stops the fire

In some instances, it’s very simple – a bushfire starts, builds and spreads then runs into a prescribed burn area and goes out as there’s not enough fuel left to keep it going. This is most likely to happen under milder conditions or when an area has been recently burnt and fuel loads are still accumulating.

Slows the spread

When a bushfire runs into an area burnt recently or even several years ago, it might not go out but slows down instead. The risk of spotting, where a fire jumps containment lines, is also reduced when it goes through prescribed burn sites, due to reduced bark hazard which is the main cause of long-distance spotting.

Reduces intensity

Although a bushfire might burn through a prescribed burn area, along with slowing it down, the reduced fine fuel in the previously burnt area can help lower a bushfire’s intensity. This gives firefighters a chance to safely attack the fire directly rather than retreat. It can also stop flames from burning the treetops, which helps plants regenerate faster for native fauna.

Gives firefighters options

Having areas of reduced fuel in the landscape gives firefighters opportunities to develop action plans and get suppression tactics in place ahead of the fire. For example, knowing that there are lower fuel areas ahead of the fire, even if they are some distance away, means firefighters can suppress the fire with backburning or dropping retardant ahead of the flames, using the existing fuel reduced area to strengthen control lines.

Watch how 20 years of prescribed burning helped stop a bushfire from burning out the entire Mt Remarkable National Park. Then scroll down for case studies on how well this worked in this park, and others across South Australia.