Dunedin Mayor Peter Chin and city council chief executive Jim Harland have written a joint letter to the ORC, calling for problems at Quarry Creek, on the outskirts of Mosgiel, to be addressed.
The creek passes a block of about 40 industrial businesses centred on Gow St, and a lack of maintenance of the creek by the Otago Regional Council has been blamed for exacerbating flooding in the area.
Periods of heavy rain had seen the creek's flow backing up, with water instead pouring into some of the businesses at least four times over the past five years.
The Otago Daily Times has also learned the repeated damage has prompted a rethink by at least one business owner's insurance company, which decided to withdraw coverage for flood damage after repeated inundations.
Chris Adams, of Mosgiel, said his Gow St premises - Adams Plumbing and Drainage - had flooded three times between 2005 and when he sold the business in January this year.
Each time, his staff were kept busy sandbagging and moving stock out of harm's way, and he was saved from stock losses only by the fact the flooding occurred during daylight hours, he said.
He now ran a new business from a site across the street, but the plumbing company's new owners were themselves mopping up in May after torrential rain struck the area again.
"I still feel for the other people in the street. They've just got to do something about it, and nothing's getting done.
"The first time we were told it was a 100-year flood, but it's happened every year in the last three years," he said.
Otago Commercial Wholesalers owner Brendan Morrison's business had flooded "a couple of times" in the past five years, and had come "pretty close" on other occasions.
The company also took a financial hit when its insurer refused to pay for some damaged contents after one flood, he said.
"Now, if it's an ongoing thing, they're just not going to cover that side of it."
Dunedin deputy mayor Syd Brown, a long-time Taieri resident, said the recurring flooding threatened the viability of some businesses in the area, and solving the problems was a "priority" for the city council.
"There's a lot of people employed in that area and I wouldn't want to see the employment put at risk because of lack of action in something that I think there's a solution for.
"It's not a matter of telling them [ORC] how to do their job. It's telling them it's a priority that the city wants the ORC to put on trying to solve this [and] protect the industrial area from becoming inoperable."
Cr Brown believed maintenance of the waterways had changed "dramatically" in the last 20 years, reducing the capacity of the waterways to cope.
The problems were raised at last week's council infrastructure services committee meeting, with council network engineer David Dewhirst saying in a report the creek should be straightened and widened.
The topic had been discussed for years with ORC staff, who were "very reluctant" to carry out the work as the Owhiro Stream - which Quarry Creek flowed into - was already under pressure, and itself prone to flooding, he said.
Council water and waste services manager John Mackie told the meeting it was "very difficult" to get "definitive answers" from ORC staff.
"I think it does need a push at all levels."
ORC staff contacted yesterday referred the ODT to environmental engineering and natural hazards director Gavin Palmer, who said he could not comment on the detail of flooding problems in the area.
He also did not know if ORC maintenance practices had changed, and said flooding problems had not previously been brought to his attention.
However, he would be happy to meet city council staff "to resolve the issue" - including determining where responsibilities lay, he said.
"A letter should be unnecessary," he said.
