Murray Moore and Steven Cormack, of District Rd, contacted the Otago Daily Times after Saturday night's rain resulted in water pouring through their properties.
They had seen nothing like it before.
They attributed the run-off - which carved a large cutting down the hill behind their homes - to the removal of a block of pines planted in 1982 by the then Green Island Borough Council to help stabilise the Church Hill Rd landslip above their properties.
The Dunedin City Council says it will investigate the situation.
The owner of the block, Blair Welsford, who bought the clear-felled land last year unaware of the issue, says he will replant the site with up to 2500 eucalyptus trees at his own cost.
The trees were cut down in May last year by the property's previous owner.
Mr Moore and his neighbours are worried about what will happen during the time it takes for the trees to grow, and that there is nothing to stop them being felled again in the future.
The trees were planted after slips in Church Hill Rd and nearby District Rd in the late 1970s and 1980, damaging at least four homes beyond repair.
Mr Moore said the trees had done a fine job since.
In the 37 years he had lived in District Rd, he had not previously seen much more than a trickle flow through his property in a heavy downpour, he said.
Last weekend, the water coming down off the hill was "like a river".
"I'd never seen water like it before. It was a bit of a shock for me."
The water flowed through the gardens, basements and garages of several properties along the street, and came up through crevices in driveways, he said.
Land along the street remained sodden yesterday.
One neighbour was convinced there would be another landslip if the water flow continued.
"It'll go again. This is a natural water course now, and this is only the start of it."
GNS Sciences scientist Phil Glassey said both slips had a long history of creeping movement, with larger movements induced by rainfall.
Based on the Church Hill Rd slip's history and its geology, there could be the occasional slump but it was unlikely there would be a sudden mass slippage, although there were no guarantees, he said.
A former employee of the Otago Catchment Board said the intention at the time was to have placed on the title of the property on the Church Hill Rd slip a convenant that required special care if the trees were logged, but it appeared that was never done.
Dunedin City Council resource consents manager Alan Worthington said there was no consent notice or convenant on the title regarding the trees.
He noted the ultimate responsibility for drains and water run-off lay with property owners, but it was complex because the land was on a known geological hazard and the council did have an interest in looking after the community in District Rd.
"It's not straightforward. We will start the process of looking at it, but it would appear there are limited options in terms of what the council could potentially do."
However, residents' concerns were legitimate and the water situation warranted further investigation.
He would talk to other staff within the council about it.
Lee Patterson, a technical engineer at MWH, which monitors slip movement on behalf of the council, said the Church Hill Rd slip was last surveyed in late February and no movement was noticed since the previous survey. The slip was surveyed every two years.
