North Queensland has copped four days of heavy rain but authorities are warning residents in Townsville the worst may be yet to come with several days more rain forecast and the Ross River Dam hitting 212 percent capacity.
Photo: 123 RF
The dam had reached 200.6 per cent at 9am Saturday and by 1pm it had risen to 212 percent - tripling the volume of water in the catchment since 27 January.
Water releases from the dam are flooding several Townsville suburbs and floodwater has entered at least 50 homes.
Falls of between 150 millimetres and 200mm are predicted for Townsville today, amid what authorities are calling a one-in-100-year weather event.
Townsville mayor Jenny Hill said about 100 homes had been evacuated but stressed there was no risk to the integrity of the dam; the dam still had plenty of flood mitigation capacity left.
However, the council declined to offer an explanation on what the percentage figure means in reference to flood prevention.
"At the moment, what we're trying to do is manage the inflows and the outflows so that we minimise the impact downstream.
"We took a deliberate decision to allow more water to exit the dam. It's now running at approximately 872 cubic metres a second.
"That has given us a bit of spare capacity now in terms of the flood mitigation that the dam can provide."
Improvements to the dam wall, which increased its capacity, were completed in 2007.
The Bureau of Meteorology (BOM) described the situation as "severe and historic", with Townsville Airport recording 861 millimetres of rain for the seven days to 9am today.
The monsoon rain has already caused extensive flash flooding in Townsville, Bluewater and Giru.
At 3pm on Saturday rain was still falling steadily over Townsville and areas up to 100 kilometres further south with heavy falls expected to continue at least until Monday.
The Army is on hand to help with sandbagging in the city's south with homes under water and streets resembling canals.
More than a metre of water flooded Chris Brookehouse's home at Rosslea. He said he was staying at his property but would leave if levels climbed higher.
"If it does get higher, we'll go - I've never seen anything like this.
"The volume of water is just incredible. Downstairs is gone, the fridge and freezer are floating. Another five or six steps and upstairs is gone too."
Townsville resident Ashleigh was going to the gym when she saw several people displaced from the rain and opened her home to them.
"I thought I'd go to a workout and then I then I saw these guys on the side of the road - you can't not help them."
Monsoon low over Mt Isa, Gulf of Carpentaria
BOM Queensland manager Bruce Gunn said the slow-moving monsoonal trough would remain over northern Queensland for the next 48 hours.
"The risk is high for the next couple of days. Expect the peak in the rainfall to recur tonight and continue into next week.
"We're expecting possible falls in the 150-200mm and some isolated areas could get 300mm in a six-hour period, so we can expect some parts of the coast to get several hundred millimetres in a day.
"The monsoon low is now sitting between Mount Isa and the Gulf of Carpentaria Coast and that extends a trough across the Cape York Peninsula and bringing that moist onshore flow to the Coral Sea coast."
Concerns for Mt Margaret, Upper Black River
BOM forecaster Adam Blazak said heavy rain fell south-west of Townsville early on Saturday morning and would exacerbate flooding.
"We do have concerns right at the moment for Mt Margaret and the Upper Black River, we've seen really heavy rainfall there.
"We are expecting to see flash flooding for that river area so downstream from that needs to certainly take care."
Mount Margaret recorded 363mm of rain in the 24 hours to 9am and a seven-day total of 1186mm, while nearby Black River recorded a seven-day total of 1272mm.
Premier Annastacia Palaszczuk said the monsoon had settled in over the region and would be producing heavy rainfall over the next two days.
- ABC