The containment efforts of hundreds of firefighters will be put to the test on Wednesday as dry winds, low humidity and high temperatures bring the Illawarra under threat of fire.
A blaze that began at Balmoral in the Southern Highlands last Thursday had burnt out more than 15,300 hectares by last night and was within three kilometres of houses on Wilton Road at Wilton, and about 12 kilometres from the top of the Illawarra escarpment.
Rural Fire Service Illawarra zone manager Superintendent Richard Cotterill likened the blaze to the 2001 fires, which destroyed 100,000 hectares and razed almost 100 buildings, including 50 homes, in Helensburgh, Stanwell Tops, Sussex Inlet, Woollamia, Vincentia and Huskisson.
‘‘This is not unlike those fires,’’ Supt Cotterill said.
‘‘There are a number of concerns in the difficult country – deep gorge country. Should the conditions eventuate that would cause containment to be breached, the fire will travel towards the Illawarra.’’
Containment lines are considered ‘‘soft’’ in several bushland locations south-east of Picton Road, where near-vertical gorges are inaccessible to firefighters.
The RFS is expecting temperatures on Wednesday over 30 degrees, coupled with predominantly north-west winds of 50km/h that will carry the heat from inland Australia.
Supt Cotterill said conditions on Wednesday would be similar to last Thursday, when the fire travelled up to 11 kilometres in four hours.
‘‘If it were to do the same again, in five or six hours we would see fire at the top of the escarpment in the Illawarra,’’ he said.
Firefighters used Tuesday's calmer, cooler conditions to strengthen containment lines, and the blaze was categorised as ‘‘being controlled’’ – as opposed to ‘‘out of control’’ – for the first time.
A small amount of rain aided the firefighting effort, but was considered of little advantage.
‘‘Today has been an opportunity to take a breath,’’ Supt Cotterill said on Tuesday.
‘‘But once we get a bit of heat in the day [on Wednesday] and humidity drops, the fuel will dry out really quickly again.
‘‘It’s imperative that people do not become complacent just because we’ve had a shower [on Tuesday].’’