A joint Otago Regional Council-Clutha District Council strategy aimed at helping Milton residents understand and live with the effects of flooding, is close to being implemented.

Clutha Mayor Bryan Cadogan said the Milton 2060 strategy also aims to guide land use development and redevelopment in the area so that flood risks do not increase, and existing risks are gradually reduced.

ORC chairman Stephen Woodhead said the strategy, which both councils have adopted, would enable long-term sustainable occupation and development in Milton, which has a long history of flooding.

Cr Woodhead said the strategy took a principles-based approach to managing flood risk, based on key themes of safety, planning, and allowing sustainable land use. Areas with similar land use and flood hazard characteristics had been defined, and mechanisms, including land use controls, developed for controlling or managing flood risk within each of these areas.

These mechanisms broadly follow the "4R's" of civil defence and emergency management: reducing risks, maintaining readiness for floods, planning the response, and taking recovery action. They include both council and community-based activities.

The characteristics of large flood events have also been determined (including depth of inundation, velocity of water at the peak of the flood, and length of time flooding may persist) using LIDAR mapping.

The technical work used to define flood hazard, and the proposed mechanisms for managing flood risk, were presented at a public meeting in Milton on April 24, attended by 100 people.

This was followed by two open day information sessions on April 26 attended by about 90 people. Council staff also had meetings with affected and interested parties, including the New Zealand Transport Agency and 11 landholders.

The public were also given the opportunity to make formal submissions on the strategy, and responded with 19 submissions.

Mr Cadogan said a large amount of useful feedback had been provided through the consultation process. He appreciated the constructive way in which the community had responded.

The public feedback also reinforced some of the key issues raised by the strategy. One was maintaining the efficient conveyance of floodwater. This includes investigating what action could be taken to reduce the negative effects of the state highway, local roading networks, and the South Island Main Trunk Line on flood hazard; improving the capacity of the stormwater drainage system, and carefully considering the effects of any proposed physical works.

"Of the submissions which questioned the strategy's findings, most related to concerns over the boundaries of the flood risk management areas, which in some cases have now been adjusted as a result," Mr Cadogan said.

As part of its ongoing contribution to the strategy, ORC will capture additional flood hazard information during and after major flood events, and make this information publicly available.

The regional council would also continue to work with CDC to implement the other flood risk management actions specified in the strategy, Mr Woodhead said.