"He miraculously got out just in time," she said.
"We are just incredibly grateful that he is safe, that nobody was killed, because it was quite disastrous.'"
The slip occurred about 9am on Saturday, she said.
The property had no issues during past rain events and the slip came "completely out of the blue - it's out of nowhere'".
She believed the cottage was a "write-off".
"I'd say it's not salvageable at all,'" Duell said.
"It's completely off its piles. It's just sitting right on the edge of the estuary.'"
The cottage had great sentimental value for her and her husband Kyle Davidson.
"It's a simple little cottage but ... it's got memories and history and charm, so it's really sad that it's gone,'" she said.
"It's another piece of history gone from the peninsula.
"We are completely devastated.''
Elsewhere on the peninsula contractors continued clearing slips which had cut off residents for much of the weekend and Harington Point residents attempted to pump water from heavily flooded paddocks and yards.
Harington Point Rd resident Sherrie Valli's property was still inundated.
The floodwater came within centimetres of her floorboards and washed through the garage and stables of the property, which her family only moved into in January.
"Every time it rains this property floods ... but never as bad as this," she said.
The water surrounding her home almost reached her knees and still covered the first steps into her house yesterday.
"It started on Friday afternoon at 1 o'clock," she said.
"We woke up at half-past five on Saturday morning and it was flooded like this.''
Despite the extent of the flooding, she was philosophical about her situation.
"Others in Dunedin have lost their houses. We haven't lost our house.
"We are just surrounded by water.''
She was watching the forecast with trepidation and was "very stressed'' about the prospect of further rain.
"If we get another lot of rain it will [flood],'' she said.
Another Harington Point Rd resident, whose house was affected by flooding, said about 10 properties in the area had been flooded.
Floodwater had run through the rear of her property and into her laundry, stopping just short of carpet inside the home.
Others had water "pretty well up to their doorstep'', the woman, who did not wish to be identified, said.
Some residents had to leave the area and stay with family or friends after water infiltrated septic tanks in the area.
She was also concerned about rain in the coming days.
"We aren't even coping yet.''
Emergency Management Otago yesterday added a Harington Point residence to its list of 143 properties evacuated following the deluge.