Warning floods in NT town hit by tropical cyclone Megan could be ‘one-in-100-year’ event

Residents have been warned that dangerous and potentially record flooding could occur in the wake of a tropical cyclone.

A “one-in-100 year flood” is set to bear down on a town already hit by tropical cyclone Megan.

Hundreds of residents evacuated before the waters reached record heights but there are concerns for those who have opte dto remain behind.

Northern Territory Police Commissioner Michael Murphy made the dire warning on Wednesday to locals in Borroloola, south of the Gulf of Carpentaria and 400km east of Daly Waters.

But by Wednesday evening, the Bureau of Meteorology (BOM) said that “major flooding” was estimated to be occurring.

Borroloola was almost directly in the firing line of Megan which was at category 2 strength when it passed on Monday.

Fully 256mm, a quarter of a metre, of rain fell on the town in the 24 hours to 9am on Tuesday in atrocious weather, the BOM reported. Of that, 100mm came down just on Monday evening. A further 114mm fell the day before.

Winds of 170km/h were recorded as the storm passed.

The path of then TC Megan which passed close to Borroloola. Picture: Zoom Earth.

Hundreds of millimetres of rain has fallen in the region. Picture: BOM.

‘One-in-100-year’ event

Ex tropical cyclone Megan is currently heading into Western Australia and is expected to pass over Kununurra and Wyndham.

But much of the damage of Megan is being felt in the NT where the vast amounts of moisture it’s brought to land is now bursting rivers on its way back to the sea.

“Due to the huge rainfall we saw attached to ex-tropical cyclone Megan, the amount of water coming through the tributaries into the McArthur River is going to reach around 18 metres at Borroloola,” the NT News reported Commissioner Murphy as saying.

The water should peak on Thursday afternoon at the town. If it does reach 18 metres it will be the region’s most significant flood since at least 2000.

Significant flooding due to Cyclone Megan has cut off roads around Borroloola on Tuesday, March 19. Picture: Polly Farmer Foundation

“A one in a 100 year flood is really serious, we’re taking it incredibly seriously and we’re doing everything we can to make sure the residents of Borroloola are safe.”

On Wednesday 400 residents were evacuated from in and around the town from Borroloola’s airstrip.

The waters were already so high some people had to be taken by boat to the airfield.

Commissioner Murphy added that four tonnes of food and water had been delivered to the town for anyone who decided to remain behind.

Significant flooding due to Cyclone Megan has cut off roads around Borroloola on Tuesday, March 19.

‘Dangerous, record flooding’

The BOM said the flooding on the MacArthur River was likely to be “dangerous”.

“The flood peak is estimated to be around McArthur River Mine on Wednesday evening, and is likely to pass through Borroloola during Thursday afternoon with record major flooding.

“Rainfall totals of up to 380mm were recorded across the McArthur River catchment over a three-day period to 9am Wednesday. Showers and thunderstorms are forecast for the next few days.”

Borroloola is still recovering from damage to local roads after Cyclone Lincoln swept through the region a few weeks ago.

Megan is the fifth cyclone to hit the north of the country this season.

Earlier, photographs shared by residents on Groote Eylandt showed the extent of the destruction.

They show trees ripped from the ground as well as yards and roads flooded following almost half of the average annual rainfall falling over the weekend.

The rain gauge at Groote Eylandt airport recorded 431mm of rainfall in the 24 hours to 9am on Sunday, making it the region’s second wettest day in 103 years of records.

It brings the total rainfall to 680.4mm in just 48 hours, more than half of the average annual rainfall of 1275.2mm.