Fixing Tauranga's storm water issues could cost hundreds of millions of dollars, so Tauranga City Council is going to change its approach.

Public consultation is being sought on the Long Term Plan over changing the storm water approach from the traditional one of preparing for a one in 50 or 100 year flood, to one of providing a safety based level of service, that of reducing the risk to people's safety.

The council proposing to focus on safety instead of damage.

The cost to deliver any level of service to reduce the risk of damage to the city's built up areas and suburbs from intense rainfall events is high, both in terms of capital and operational costs.

'There was nearly unanimous support to go with what's in the agenda in terms of level of service,” says Mayor Stuart Crosby.

'We agreed to consult on the one in agenda priority on safety. The funding component also went through, with strong support for consultation.”

The council will continue with more than $10 million in storm water works planned over the next three years, including the work in the Otumoetai and Maleme Street catchments, says Stuart.

'If we carried on trying to address the storm water problem to a high level of just about protecting everybody's property, we would be looking at over a quarter of a billion dollars.

'Throughout this whole annual plan we have looked at two key principles, financial prudence and public safety. So when you put those together we believe our level of service.”

The change puts a lot of the onus of flood control in the hands of individual property owners. Regulatory changes will focus on owners' responsibility for the flood waters that leave their property.

They may be required to install on site storm water detention to reduce peak flows. There will be restrictions on increases in impervious surfaces, i.e. property owners may no longer be permitted to export floods to their neighbours by concreting their yards.

Overland flow paths will be protected by restrictions on building development within overland flow paths and floodplains.

Along with the shift in focus, there will be an educational programme providing risk reduction and technical advice and

'It's the first time in the whole storm water debate since the 2005 floods that we now have a uniform level of service across the whole city,” says Stuart.

There is still work to be done. The modelling funded by the levy on rates will be completed, and they city engineers will begin accurately measuring floor levels of homes in hot spot areas.

'That will be fed into the hot spot data base,” says Stuart. 'So the safety of life is primary, that's where we have high volume water flows going through private property that will be our priority.

'We will amend our city plan also and embark on very strong community engagement and education process in terms of educating people about obstructions they can put on their property that makes the situation worse.

'Because that's what we found in April 2013, there were obstructions built on property creating some problems, and we're looking to financially support people in areas that require onsite changes.

'It is a whole package based on safety, regulation, education,” says Stuart.

The council is also looking at building up a $20 million flood fund that it can draw off for hot spot areas.

An immediate effect of the change of council stance can be seen on two looming projects, the Bayfair to Baypark highway redevelopment, and the Pheonix carpark transformation in Mount Maunganui north.

The decision means the council will not be taking the opportunity to put in $6 million in storm water to reduce flood risk in Eversham Road. While the works will reduce the flood risks to a few properties there is no modelled safety risk.

It does affect AMP's growth plans for Bayfair which cannot grow until the storm water service is improved. AMP will have to find another solution.

The Phoenix carpark is a low point and re-configuring the associated storm water system would normally be looked at in the circumstances. Under the new policy, it won't be.