Many Auckland homes at risk of flooding and water and wastewater issues in heavy rainfall
Nearly 70,000 homes in Auckland are prone to flooding and 50,000 properties face capacity issues with water and wastewater during heavy rain, according to council data.
What’s more, until recently the council had been relying on a 2006 report to map the dangers of coastal erosion, which left numerous houses teetering on the edge of cliff faces after the January 27 floods.
These numbers are contained in the council’s response to plans by the Government and National for greater intensification in Auckland, which the council now wants reviewed.
The record rainfall that battered the Super City has brought acknowledgement from Prime Minister Chris Hipkins of more extreme weather to come and the need to look at where houses and businesses are built.
With a real-life view of the city’s infrastructure and planning shortcomings in the form of watersoaked carpets and sofas littering streets front of mind, councillors set up an urgent review of the council’s plans, regulations and policy settings on Thursday.
Planning committee chairman Richard Hills said the current focus was rightly on helping people affected by the flood, but there was a need to give people answers about managing future risks.
“This is climate change . . . this is what people have been saying for 30 years would happen. It has just unfortunately come much faster than what we hoped for,” he said.
Many of the 67,797 homes in Auckland vulnerable to flooding are in well-known locations, such as Henderson and New Lynn, plus Remuera, Pakuranga Heights and Milford.
One area hit hard by the floods is the Albert-Eden-Puket¯apapa ward on the central isthmus where 63 houses have been red-stickered and a further 443 yellow-stickered, indicating they are uninhabitable or have limited access.
Watercare has identified 50,918 sites in Auckland that have water and wastewater constraints. Impacted areas include the Hibiscus Coast and lower North Shore suburbs including Devonport; Henderson-Massey out west; Howick in the east; and Mt Eden, Herne Bay, Grey Lynn and Ponsonby in the central city.
Watercare says it could be the mid2030s before new water connections make it feasible to intensify around Devonport and Northcote Point, and a pump station serving Henderson and Massey is already over capacity and causing sewage overflows. It is not due to be fixed until 2035.
The council’s Healthy Waters stormwater division has identified 511 sites in the central isthmus around Mt Eden and Epsom that have no ability
to connect to the public stormwater network and with constrained ground soakage capacity.
The city also faces “significant risk” from coastal erosion. A recent report from environmental and engineering consultants Tonkin and Taylor found the provisions in the Auckland Unitary Plan, based on a 2006 report, underestimated hazards in many areas.
Before January’s floods, the council said recent information on sea level rise and revised predictions of storm events indicated the coastline was under threat of increasing erosion, and recommended avoiding further development in areas susceptible to coastal erosion.
The council is seeking to exempt these hazard risk areas from Labour and National’s directive to give anyone the right to build three houses up to three storeys high, with only a smidgeon of green space, without resource consent.
The council says if the Wellingtonimposed plans for more intensification just about anywhere in suburban Auckland are implemented, up to 3.3 million more homes could be built by 2051. The council’s Unitary Plan allows for the construction of 900,000 homes in the same period.
Despite growing pushback in Auckland, Housing Minister Megan Woods and National’s housing spokesman, Chris Bishop, are holding the line on their controversial intensification agenda.
Woods said that after decades of restrictive zoning by councils in the largest cities, it is appropriate for the Government to amend the Resource Management Act and put plans in place to ensure there is sufficient housing for communities.
Bishop said National remains committed to enabling the construction of more homes in the largest cities.
Both MPs said the Housing Supply Act for the so-called three-pack housing provide councils with the power to exclude areas from further development if they are prone to a natural hazard.
Woods said that the Government had invested in stormwater infrastructure at some large-scale projects in Auckland that had handled the floods extremely well.
She cited the transformation of Greenslade Reserve into a stormwater detention basin as part of the Northcote development for 1700 new homes, saying the works prevented the adjacent town centre from being flooded.
In K¯ainga Ora’s Roskill development, Te Auanga Oakley Creek experienced significant overflow through some areas of Wesley, said Woods, but where new stormwater infrastructure had been installed, the water drained away quickly.
The Act party is opposed to National and Labour’s plans, with deputy leader and Auckland-based MP Brooke van Velden checking locals, delivering warm dinners to families and hearing from residents opposed to intensification in the days following the torrential thunderstorms.
Writing in the Herald this week, she said Act was not opposed to intensification, but against the kind of unplanned, unresourced intensification that had been pushed through Parliament.
“Allowing three, three-storey townhouses on any section without conditions is a recipe for more disasters. Councils should be able to halt such plans where they are not confident they can provide the infrastructure,” she said.
At Thursday’s planning committee meeting, councillor Chris Darby said more than 2000 homes were given consent in hazard zones in the past 12 months, saying that, in November and December last year, 18 per cent and 16 per cent of new dwellings consented respectively were in flood and erosion zones.
“I never realised that we were consenting so many buildings to be built in such places and then thousands of people to be put in those places — to live, but maybe not fully understand the place that they are living in.”
He called for a risk-averse approach on behalf of the wider community for processing applications in hazard zones, which council strategy boss Megan Tyler said could pose legal difficulties.
A leading water expert believes the solution to further floods arising from climate change is a new green plan for the city.
Dr Matthew Bradbury, an associate professor at the School of Architecture at Unitec — Te P¯ukenga, said the current Compact City plan is a response to urban sprawl with twostorey houses built in a grid pattern with a lot of impervious surface.
The model he is advocating is “a lot greener” and a response to what the “natural landscape is telling us”.
Preventing floods is impossible, said Bradbury, but they can be slowed down by restoring streams and wetlands, as is happening with the Te Ararata Stream team in M¯angere replanting banks and rebuilding a crucial urban stream.
The restoration of the Waiatarua wetland in Remuera, the Vaughan stream corridor wetlands in Long Bay and the Kopupaka Reserve in Westgate are other examples.
Bradbury said Auckland could also follow the example of Copenhagen, which was hit by extreme rainfalls in 2011. “Their response was to develop a comprehensive flood protection plan. They rebuilt parks to detain flooding and redesigned streets to convey flooding.
“We have a great opportunity in T¯amaki to design and build a similar system.
“Unlike Copenhagen, we are not so dense. We still have remnants of the old stream system and many parks.
“This is an opportunity to propose a comprehensive network of restored urban streams and detention parks, which can act as a new open space for all of Auckland’s unique populations.”
Bradbury is the author of Water Cities, a book that discusses the connection between the effects of climate change and urban design.