The onus will fall on city and district councils to control what is going into their stormwater systems, under the Otago Regional Council's proposed urban water quality strategy, ORC environmental information and science director John Threlfall says.
Councillors called for the strategy to be developed earlier this year after recognising while the council had been focusing on rural run-off pollution, similar problems existed in urban areas.
At a meeting today, policy and resource committee members will discuss the strategy which aims to, at a minimum, retain the water quality status quo and over time reduce the impact of stormwater on existing urban locations.
Dr Threlfall said unlike the rural water quality strategy which involved landowners controlling their run-off, in the urban system, the responsibility of the quality of discharge was generally with local city or district councils or in some cases developers.
Of immediate concern was the Queenstown and Wanaka areas where urban development was rapidly expanding often next to rivers and lakes with "pristine water", he said.
"We must control [the run-off] so it does not deteriorate over time."
It was hoped the strategy would mean councils would put greater pressure on developers to ensure they had good systems to ensure run-off into those waterways was not polluted, he said.
While it was difficult to clean up systems already long developed, such as the Dunedin system, work had and was being done by the Dunedin City Council on issues like connections between the sewer and stormwater systems.
"Their philosophy fits the strategy."
Under the strategy, the regional council would monitor discharges "at the end of the pipe" more frequently.
The water quality standards for these discharges had yet to be decided upon and would be developed over time, he said.
At today's meeting, the committee is being asked to endorse the strategy, which will be consulted on.
