The threat caused by the rising sea level means new homes in
some coastal areas of Dunedin will have to be built up to
1.2m higher off the ground to reduce the risk of being
The changes announced by the Dunedin City Council yesterday
apply to the floor levels of residential or communal
buildings and extensions, but not to industrial or commercial
The new minimum levels, on average 75cm above the previous
level, do not apply to South Dunedin because of the
protection provided by sand dunes and the way the area has
The previous level was 2.15m above the mean sea level in
Dunedin measured in 1958 and 29mm above the previous highest
recorded tide in Dunedin in March 1980.
About 7000 properties close to coastal areas have some, or
all, of their land below the new minimum floor level, of
which 5400 are in South Dunedin where the existing rule will
The new levels apply to 1560 coastal properties, mainly in
and around harbour towns, of which just under 1000 are in
residential or communal use.
The change also meant flood warnings were yesterday added to
properties in coastal parts of Dunedin, including South
Dunedin, which Cr Kate Wilson said had potential to affect
both property values and insurance costs.
The information, added to Land Information Memorandums (LIMs)
yesterday, warned owners and purchasers houses below the new
minimum levels could be subject to increased flooding risk
over the next 50 years "from elevated sea-level rise
associated with climate change".
The new levels ranged from 45cm above the previous levels in
the upper Otago Harbour to 1.2m above in the suburb of
Cr Wilson said at a media conference yesterday the change
could have a "dramatic" effect on people wanting to build
homes or extensions in low-lying areas.
"It's a relatively small number of properties in Dunedin, but
it will affect some people quite dramatically."
Asked if the council had looked into how much extra it might
cost to build on affected properties, she said: "The focus
has been on how we can protect that investment, rather than
how much it would cost them, because it would cost them a
much greater amount if they had a property that was likely to
The message was that if you were investing in these areas
"you need to look at this issue".
Dunedin Mayor Dave Cull said the council, along with "all
coastal councils", had a statutory obligation to include the
warning on LIMs under the Local Government Official
Information and Meetings Act.
Council operations general manager Tony Avery said the
changes were based on predicted sea level rises, a report on
floor levels by engineering company MWH provided to the
council last year, with differences in local areas based on
an Otago Regional Council report looking at vulnerability to
elevated sea levels.
The changes had implications for applications for building
consents, resource consents, subdivision consents and could
result in district plan changes, he said.
The changes were just the start of the council's response to
the threat of sea level rises.
"There are some big questions we are unable to answer at the
moment, but we are taking a precautionary approach," he said.
Real Estate Institute of New Zealand Otago regional director
Elizabeth Nidd said she did not think the changes would have
a major effect on property prices.
"In most situations, people are going to be aware [of the
risks] anyway, so it's kind of a statement of the obvious.
"It's just another small hurdle for us to get over," Ms Nidd
Insurance Council spokesman Chris Ryan said having the new
information included on LIMs would be "unlikely" to affect
insurance prices "in the next year or two", but could in the
Otago Master Builders Association president Mark Ward said
the cost of the minimum floor height standards would likely
be small and depend on the location and design of the house.
"It will probably add to the cost of build a little bit, but
not much," Mr Ward predicted.
The change would be more difficult for people wanting to
build extensions in low-lying areas.
"It will be difficult and dopey, because you wouldn't want to
walk up three flights of steps to get to your bedroom."
It could also add stress for people part way through
designing extensions or new houses, but yet to apply for
"It could cause a bit of chaos. I mean if you were building a
house right by the sea, you might have to redraw your plans."
Waikouaiti Coast Community Board chairman Gerard Collings
said while he understood some people living in coastal areas
could be annoyed by the changes, it would be "negligent" of
the council not to make the information available to
"My feeling is that it's prudent for council to signal and
clearly enforce an appropriate floor level," Mr Collings
Saddle Hill Community Board chairman Keith McFadyen said he
was keen to discuss the changes with residents and the issue
would be discussed by the community board.
ORC chairman Stephen Woodhead said it supported the move by
"We support their endeavours to use the latest information
for building control and planning purposes," he said.
Although the Waitaki District Council was aware of the issue,
there were no plans for height restrictions in the district.
However, council planning manager David Campbell said the
resource consent procedure for coastal areas already
addressed the situation in a secondary way, as flooding
hazards were covered in the district's coastland landscape
plan, although it was primarily intended to protect
The situation would be reviewed as part of district plan
procedure in two years' time, he said.
Raising floor height*
- Brighton (all coastal land
south of Blackhead)120cm
- Coastal peninsula area (Hoopers
- Upper Otago Harbour55cm
- Karitane, Flag Swamp and
- Long Beach, Aramoana,
Purakaunui, Port Chalmers, Sawyers Bay, Harwood, Warrington,
*height is above previous minimum floor height