So paramedics went to her Airlie Beach home, which had lost power, and found her in darkness in the bathroom, having contractions every two minutes.
The initial plan was for the SES to ferry her down the river from Airlie Beach to Proserpine Hospital.
"But, I decided that, no, it was too dangerous as her contractions were growing stronger every minute and it's dark," paramedic Pamela Price said.
Instead they took Suzanne to the nearby Whitsunday Ambulance Station, where lights and equipment had been rigged up from a generator.
A few hours later, at 4.20am, baby BillIanna was born.
"We did call in an off duty doctor," Ms Price said.
"She came along and oversaw us."
Ms Price described the delivery in the midst of Debbie's chaos as "surreal" and "absolutely amazing."
"I have been on the other end of the situation but never actually assisted a mother to deliver a baby," she said.
"It was beautiful. Everyone was crying and hugging each other. It was wonderful."
Premier Annastacia Palaszczuk called Billianna's arrival a piece of good news in a devastating situation.
Ms Price agreed.
"This place is shredded, there's mass destruction everywhere so to see this absolutely beautiful birth of a most beautiful little girl... all the spirits are lifted."
In a second boost, another baby girl was delivered at an ambulance station at Nebo, about 100km southwest of Mackay, at 10.34am on Wednesday.
Queensland Ambulance Service said the healthy newborn and her mother were still at the station due to road closures but were doing well.