The soaked staff of a Mosgiel store stacked compost bags last week to stop floodwater swamping neighbouring businesses.
More than 175mm of rain fell in the 24 hours to 4am Thursday and heavy rain fell continuously for 17 hours.
Mitre 10 Mega Mosgiel staff manager Steven Loughrey said after hours of the deluge, Mosgiel business owners feared the worst as floodwater approached the businesses.
''Most of the floodwater was coming from the wash off the cars,'' Mr Loughrey said.
Mitre 10 Mega Mosgiel assistant manager Rachael Corbett acted by getting Mosgiel police to block Gordon Rd to stop the wakes.
She deployed Mitre 10 Mega staff Vorne Restieaux, Logan Adams, Dave Hellyer and John Woodhead to lay three pallets of 40-litre bags of compost along 50m of shop frontage on both sides of the road.
Compost bags were as effective at stopping water as a sand bag, Mr Loughrey said.
The 150 compost bags remained on the footpath overnight and the staff collected them the next morning.
Mr Restieaux said staff stopped flooding in the same spot about two years ago.
''It's something we've done before and it's something we'll do again.''
The bags were waterlogged, but would dry, and would be sold at a discounted price, he said.
Gary Roberts, the owner of women's clothing shop Curve in Gordon Rd, said most of his 200sq m shop was flooded.
The shop was insured and had been flooded three times in the past three years.
Although he was peeved the shop had flooded again, he applauded the council's past work to increase the capability of stormwater drains.
In past floods, he had argued with the council about its response to flooding but the response this time was hard to fault, he said.
''It couldn't have been better''.
The rain was simply too heavy for the stormwater system to cope.
Mr Roberts thanked the quick action of Mitre 10 staff, and the compost kept the floodwater ''at bay'' until about 4pm Wednesday.
''Then it was just too much.''
His shop and the business next door, AMI Insurance, was ''flooded to the back wall'', but his other clothing shop, Private Label, a few doors down, was dry.
