The worst of the unparalleled fire risk faced by the Blue Mountains has been averted as it emerged army explosives training started the massive blaze that has threatened thousands of homes and lives.
The Rural Fire Service (RFS) said an investigation had found the Department of Defence training exercise last week was responsible for causing the State Mine blaze near Lithgow, which has burnt out more than 46,000 hectares and sparked fears of turning into a ‘‘mega-fire’’.
‘‘The investigation has concluded the fire started as a result of exploding ordinances on the range on [last] Wednesday,’’ a RFS spokesman said.
But the department would not confirm its responsibility yesterday, only repeating it was investigating the exercise on army land at Marrangaroo.
After the anticipated dire conditions arrived in the mountains and the Hunter region, RFS commissioner Shane Fitzsimmons said high risk strategies from firefighters had paid off.
‘‘We have seen today, and indeed building throughout the week, one of the most significant threats to the Blue Mountains and Hawkesbury communities that is unparalleled,’’ he said.
‘‘Never before have we seen the extent of damage and destruction and wide scale fire activity at this time of the year.’’
But, late yesterday, he followed that with words the hundreds of Blue Mountains residents who had left their homes had been hoping to hear.
‘‘It would be safe to head back home tonight because the risk has been averted,’’ he said.
Only one fire, near Gateshead at Lake Macquarie, remained subject to an emergency alert yesterday evening.
Mr Fitzsimmons said the Gateshead fire was now burning right through the middle of the two towns it had initially threatened – Redhead and Dudley.
As hot and windy conditions began to ease yesterday afternoon, a major blaze at Minmi that closed the M1 near Newcastle and caused the evacuation of two schools, was also downgraded to watch and act.
The Springwood blaze in the Blue Mountains, which had showered homes with embers as strong winds sprang up, has also been downgraded.
All schools in the Blue Mountains were closed yesterday, but only a select few will be closed today.
Mr Fitzsimmons said he was surprised backburning in the Blue Mountains had held out in the extreme fire conditions.
A south westerly change today could bring lower temperatures but could still pose a risk to some communities.
‘‘It has the very real potential to present new challenges and particularly in the northern end of the Winmalee Springwood fire... that fire could pose threats tomorrow to communities in the Yarramundi Valley area and communities up through Grose Valley and communities to the north east,’’ Mr Fitzsimmons said.