Plan to bring forward flood mitigation spending in Wellington

20 May 2015

A proposal to bring forward $8 million in flood mitigation spending – prompted by the three severe rainstorms that have hit the capital in the past month – is to be recommended as part of Wellington City Council’s 10-year Plan.

Floodwater surrounds a house.

A front yard in Tawa, flooded after heavy rain


Wellington Mayor Celia Wade-Brown says, if the proposal is finalised in June as expected, a total of $18 million will be available for spending over the next three years on up to five flooding “hot spots” around the city.

The areas – all of which suffered flooding in the past month – include the Kilbirnie Crescent area, the Basin Reserve area, the bottom of Aro Street, Lyall Bay Parade and parts of Tawa – parts of the Main Road commercial area in particular.

Mayor Wade-Brown says engineers have completed preliminary reports on the rainstorms and the resultant flooding. “The task now is to work with people in these areas on the solutions.

She says while all three rainstorms were particularly heavy, it is the City Council’s responsibility to prevent flooding as much as practicable. “While the city has generally coped well with the last three storms, there is more work to do. We will be looking at both short-term ‘quick fixes’ and also longer-term responses that will take into account modelling on climate change and projected sea-level rises.”

Councillor Iona Pannett, Chair of the Council’s Environment Committee, says she has been working with the Council’s infrastructure staff and management from Wellington Water on possible responses to the flooding events.

She says a combination of initiatives may be considered – everything from expanded drainage mains and new pump stations, to the possibility that the Council may pay for some houses in particularly low-lying areas to be raised on their foundations or for waterproof doors to be installed on some flood-prone commercial properties.

“It is the Council’s intention to implement some of the easier fixes over the next few months and year. Other changes will take more time. We need to pick the right solutions to get the best value for ratepayers.  The next three years should see significant progress on some of the large infrastructure projects needed to deal with stormwater in the future.” 

The Council may also have to consider possible property purchases and also District Plan changes that could guide the construction of new buildings and facilities in flood-prone areas.

Cr Pannett says while many millions of dollars have been spent on flood mitigation work in parts of the CBD, Island Bay, Miramar and Tawa over the past two decades, “it is clear we have new challenges. We are taking this issue very seriously – and I am impressed that our engineers have worked long hours in the past couple of weeks to not only deal with the floods themselves but also produce comprehensive reports and recommendations on spending priorities.”

She says Wellington Water is also starting a major rainfall and drainage modelling project that will help councils across the region plan properly for flood-mitigation investment over the coming decades. “As we saw last Thursday, this is a regional issue – so we want to be sharing this information for the benefit of the whole region.”

Mayor Wade-Brown says the flooding in the past month has provided a salutary reminder to Wellingtonians that the region faces a range of natural hazards – including severe rainfall events. “It’s a good opportunity to also remind people that they should have emergency packs at home and at work, and they should have emergency plans.”