‘Sinkholes’ appearing in Byron Bay

Chris Dobney

Byron Shire Council say they have fixed a massive pothole in Sunrise Boulevard that opened up ‘overnight’ this week, according to an Echonetdaily reader.

Long-time Sunrise resident Niqui Yazdi said she believed the pothole, which was large enough to put a wheelie bin in, was in fact a ‘sinkhole’ and that a dozen of them had appeared equally spontaneously around the Byron Bay suburb of Sunrise in the last decade.

Ms Yazdi said a similar sinkhole that appeared ‘just around the corner from this one’ about a month ago was large enough to fit a shopping trolley.

‘We do get a lot of potholes out here but these along Sunrise Boulevard can be quite deep. They can be in excess of a metre deep,’ she told Echonetdaily.

‘Council’s theory is that there might be a leaking water pipe under the road,’ she said, ‘but some of these holes actually occur in side-roads as well, so it’s not just Sunrise Boulevard.’

Toilet shifting

‘This whole area is built on sand, and the theory was given to me by a plumber a few years ago that a lot of the houses out here actually have gaping holes underneath them where sand has literally sunk or shifted.’

Ms Yazdi said her toilet was ‘actually moving’ and ‘that was his theory as to why the toilet was shifting: there wasn’t anything solid underneath.’

‘He says he does find that in some of the houses out here he finds there are sinkholes where the sand has literally shifted underneath the houses.

She added that a few years ago one pothole that opened up in the road ‘would easily have swallowed a motorbike’.

A Byron Shire Council spokesperson said the large pothole had been fixed.

The council’s director of infrastructure services, Phil Holloway said Sunrise Boulevard’s recent sinkhole is not a common occurrence in Byron Bay.

He said sink holes can be caused by a number of reasons including natural processes or human activity such as failed infrastructure.

‘They can be a couple feet in diameter as was the case in Sunrise, or as was recently seen in Sydney, very large. They can appear suddenly or gradually over time,’ Mr Holloway noted.

‘Water erosion can hollow out naturally occurring underground cracks or small cavities.  When the surface can no longer support its weight, it collapses.

‘Similarly failed underground infrastructure such water main breaks, sewer collapses or old pipes giving way can cause a hole to appear.

‘The Sunrise Boulevard sinkhole was due to a collapsed drainage pipe under the road and was repaired immediately,’ he said.

Mr Holloway said the pipe in the area has collapsed several times over the years due to its age and on each occasion repaired.

‘Following the recent collapse, we are sending a camera down the pipe to check for any further defects. If found, they will be prioritised into our works program.

‘Drains are periodically inspected with a camera to help inform drainage programs,’ he said.

Mr Holloway also pointed out that road and drainage engineering over the decades has changed significantly.

‘What was once acceptable 20 years ago, is not the case today.

‘In Byron Shire we have a significant number of old roads and drainage that need to be replaced and combined with sandy soils on the coastline, it is challenging problem.’

He said he wasn’t aware of a resident’s claim on ABC radio that Sunrise had vacant holes underneath the ground.

‘It’s the first I’ve heard of such a thing,’ he said.

‘In the past 7 years, I’m aware of a handful of minor sinkholes occurring throughout Byron Shire. They have occurred due to failed pipes, following rain events,’ he said.

Sinkholes should be reported immediately to the council on 6685 9300 during office hours weekdays or the emergency number 6622 7022 after hours.