New findings from quick response fire research

New research conducted under the Bushfire and Natural Hazards CRC’s funding for quick response program has investigated the effects recent fire seasons in New South Wales and Tasmania.

With a focus on assessing building damage from bushfires, the January 2020 NSW bushfires study was led by Andrew Gissing (Risk Frontiers). In late January 2020, the research team visited the NSW South Coast to survey fire damaged buildings around the Moruya, Mogo, Malua Bay, Rosedale, Batemans Bay and Lake Conjola areas. The research team collected non-perishable data in the form of photos of building damage, mapping and geospatial analysis of building damage to assess building vulnerability and the extent of impacts after a fire.

In total, 426 properties were assessed, with the team finding that 92% of these were destroyed. In terms of building specifics, the survey provided numerous examples of fire affected residences, primarily constructed of ‘non-flammable’ materials (brick and blockwork [piers and walls]). These structures demonstrated some resilience to the fire, at times remaining wholly or partially intact. However, the remaining material comprising the premises (structural roof/wall timbers internal walls and house contents), once alight, would ultimately render the entire building to be unsalvageable (destroyed). Timber beams supporting house roofs and carports were uniformly level on the ground (as though dropped). Metal framed buildings (e.g. sheds) and structural elements (e.g. lintels) did not perform well - failing due to extreme heat and leading to the building warping and impacting brick/masonry when collapsing.

At partially damaged properties, the building features most often impacted were constructed from timber such as external stairs, decking or to the side of buildings which were a fascia material not further described.

Access the full summary report of findings here.

Re-measurement of burnt permanent plots in Tasmanian wet eucalypt forest – 2019 investigated the effects of fire at 12 permanent plots that burned in the 2019 Tasmanian fires. In January 2019 the Riveaux Road bushfire burned over 63,000 hectares in southern Tasmania, including 12 permanent fuel monitoring plots in a range of Tasmanian Tall Wet Eucalypt forests that stand across south east Tasmania. Tasmanian Tall Wet Eucalypt forests are the most complex and poorly-documented forest ecosystem in Australia, and due to the contrasting flammabilities of their vegetation, fire behaviour is poorly understood in these forests.

Lead researchers from the University of Tasmania, James Furlaud and Prof David Bowman, remeasured fuel loads and vegetation, collected and measured all dead and live fuels on the surface floor, and measured the burnt-tip diameter of shrubs in the area. By measuring these more well-established indicators of fire-severity, the researchers confirmed that the approach of comparing flame height to canopy height is a good indicator of general fire severity, and by measuring post-fire fuel loads, they developed an understanding how fire severity is influenced by fuels and time, especially as fire is a critical question in these unique forests.

Access the full summary report of findings here.