The Mosgiel-based firm - which was not named - was issued with a $750 infringement notice, and ordered to pay costs totalling $918, Otago Regional Council director of resource management Dr Selva Selvarajah confirmed yesterday.
The company was responsible for mistakenly cross-connecting sewage and stormwater pipes during construction of a house in the Orchard Grove subdivision, East Taieri, in the middle of last year, he said.
The error meant raw human waste emptied into the nearby creek, which was a popular play area for some of the neighbourhood's children.
A second plumbing company - also not named - was ordered to pay $918 in costs for its part after its staff replicated the mistake while working off the original cross-connected pipes while connecting a second, adjacent, house.
Both errors were corrected before the second house was occupied, meaning it did not contribute to the discharge of raw sewage, Dr Selvarajah said.
The possibility of a prosecution of the companies had been considered, but the fact the companies had moved quickly to rectify the faults, and co-operated fully with the ORC investigation, meant that was not necessary, Dr Selvarajah said.
The original error had occurred because drainage lines marked by coloured stakes, placed in the ground to guide staff installing the pipes, had been disturbed.
The staff had continued the work without referring back to original plans to check their connections, leading to the cross-connection, Dr Selvarajah said.
Dunedin City Council staff had made an initial inspection of the drainage lines but had failed to check the pipe connections had been adequately completed.
However, after the ORC launched its investigation, DCC staff announced changes to their inspections process in October, meaning drainlayers would in future have to convince council inspectors the pipes were properly connected.
That could be through a verbal description of what steps were taken to ensure proper connections, but council inspectors could also conduct independent tests - such as a dye test - to ensure the connections were correct.
Dr Selvarajah said the ORC was also seeking more information from the DCC, in order to verify the city council's new procedure was adequate.
"We are satisfied with the list of checks they have got but what we are looking for is how the checks are being made," he saidDCC development services manager Kevin Thompson said he had not yet seen a report from the ORC and could not comment.
