28 Sep 2020

NZTA hushed historic Auckland Harbour Bridge contamination

8:33 am on 28 September 2020

Auckland Harbour Bridge maintenance work and operations contaminated land next to houses with heavy metals above permitted levels, but the Transport Agency opted not to tell local people.

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Photo: 123rf

This is revealed in a dozen documents obtained by RNZ, about tests done a decade ago - documents that also say the bridge's resource consent conditions were being broken.

Soil tests aimed at renewing those maintenance consents in 2010 found high and rising levels of lead, zinc and copper in topsoil at Te Onewa/Stokes Point, caused by sandblasting and traffic.

They also found a cancer-causing hydrocarbon, Benzoapyrene, at up to 30 times permitted levels, the source of which is probably fill dumped decades ago, the documents say.

Documents obtained by RNZ show an internal argument went on for two years within NZTA over whether to tell two dozen nearby households.

It sought legal advice in 2011 on the liabilities around delaying going public, which it was told were many.

The city's top public health officials advised the agency in January 2011 to tell people, and test their properties.

It didn't.

"It never happened, they've never been told," said Carl Reller, the agency's national environmental manager at the time, from 2007-14.

It was a tiny project, but as soon as his team started, "the bells went off".

"It was completely kiboshed and hit on the head" by NZTA's Auckland regional office, he said.

"Every time I got it on the agenda, it would be pulled off the agenda at the last minute."

The agency would not be interviewed, but in a statement to RNZ said it was up to the Auckland Council to determine what to tell the public about contamination.

The risk from lead dust spreading from the bridge had been reducing, as lead paint was progressively removed in operations where containment had improved since 2011, it said.

As for contamination levels now, the agency said only that additional soil tests in 2016 showed similar levels of contamination to 2010.

These were gathered as part of building the Te Onewa Pā Walkway, and supplied to the council, which ruled no resource consent was required under the National Environmental Standards for Contaminated Soils, the agency said.

A study by UNICEF says about 800 million children worldwide could be affected by lead poisoning. It says lead is a potent neurotoxin which causes irreparable harm to children’s brains, and can cause an increase in crime and violence.

Photo: 123rf

'Elevated risk'

Two rounds of tests; in 2010 and 2011 were carried out in a small area of council reserve land, 50 metres either side of the bridge's landfall, found:

  • a quarter of almost 400 samples breached background or permitted concentrations
  • there was "an elevated public health and environmental risk"
  • lead was at up to 3.5 times permitted levels
  • the hydrocarbon BAP (benzoapyrene) was up to 30 times permitted levels
  • zinc was very high (it is toxic to plants and animals, but much less so to people), and copper was elevated, with chromium steady

A 'stakeholder engagement plan' done by the agency in January 2011 said the greatest concern was lead.

"While these levels would not be expected to cause acute harm, they would affect most sensitive receivers over a long period of time," the plan said.

It added there was no safe level of lead exposure for children.

The documents support Carl Reller's account of championing the cause of going public.

"What I wanted to do is to find out if that contamination existed in the residential yards, and especially: were there children in those yards, or daycare centres?" Reller told RNZ from Wairarapa, where the 71 year old is now retired on a lifestyle block.

He told regional managers the contamination was not that severe, was in a narrow band beside the bridge, and could be easily remediated, he said.

"Senior managers told me, 'Well, everyone is going to get upset everywhere, and they're all going to think they're contaminated'.

"They didn't want to talk about it for fear that the general public would have concerns."

A street near the Stokes Point Reserve, in Auckland.

A street near the Stokes Point Reserve, in Auckland. Photo: Google

An agency lawyer told managers in February 2011 in legal advice about liability:

"The sooner the NZTA gives notice to landowners of the possible existence and cause of such contamination, the sooner the NZTA can be confident that the limitation period in relation to civil claims for damage to property has begun to run.

"There would be measures that residents could take to reduce the health risks related to that contamination, if they knew that the risk existed, e.g. not allowing their children to eat the soil."

The agency's upper management knew what was going on, but did not get involved, Reller said.

In his seven years in charge of environmental management at NZTA, this was typical, he claimed: The agency would spend up large on noise-abatement walls and stormwater ponds, even if they did not work. But it tried to limit the public view by going for non-notified resource consents, and when things went sour and it was in the gun, often the agency would disregard the public's right to know, he said.

Implications for owners

The Auckland Regional Public Health Service foresaw ongoing problems from the harbour bridge contamination, once it learned about it from NZTA.

"There are implications for both present and future owners, and we support the present owners being involved in the investigation," said a letter in early 2011 to the agency, signed by Auckland's Medical Officer of Health Simon Baker.

"A means to alert future owners to the findings (including peripheral findings not breaching human health guideline levels) would seem to be appropriate via council property records."

Controls over maintenance work at the bridge were part of the first resource consent conditions, in 2001.

These mandated sampling being done - and if contamination was found, telling residents, said an agency report, in April 2011.

In 2001, lead and zinc maximums in Stokes Pt samples were already well above the council-set permitted levels.

At the next set of tests, for the consent bid in 2010, the lead maximums had risen 38 percent, zinc maximums had doubled (to 5500mg/kg, against a permitted 400mg/kg), chromium was up but below the threshold; and new entries to the contaminant list, copper and BAP, were excessive.

"AHB [Auckland Harbour Bridge] has a poor compliance history," said an agency report in April 2011, written for a meeting called to try to end the standoff over public engagement between NZTA's regional and national offices.

Of 15 bridge consents, eight had been non-compliant for 10 years, it said.

It quoted the head of the maintenance contractor, Total Bridge Services, saying, "'I've never seen this [Discharge to Air] consent before and wouldn't have been able to comply with it'."

RNZ has approached the owner of Total Bridge Services, Australia's SRG Global, for comment.

Carl Reller said it wasn't the bridge contractor's fault, but the agency's for not passing the consent on.

"That was a pretty common practice - to get a consent, put it in the file cabinet, and never take another look at it," he said.

The Auckland Harbour Bridge

Photo: 123rf

When he began at the Transport Agency in 2007, out of 5000 consents it held, covering 350,000 conditions, 95 percent were not being complied with, he claimed.

"The regional councils trusted that we were doing the right thing."

The push to exclude the public when it really counted, including by using non-notified consents, had got worse, Reller said.

The bid to renew the bridge consents in 2010 was rejected by the council initially.

This was because it lacked a proposal for containing some discharges, Reller told RNZ.

New consents were eventually issued in August 2011. The documents show their issuance had been separated out from the contamination investigations.

The agency did not respond to Reller's claims about consents in its statement to RNZ, on Friday.

It emphasised that bridge maintenance methods had improved since 2011, "to significantly reduce the amount of abrasive and paint particulates discharged to the harbour and land during bridge maintenance activities".

Lead-based paint had not been used for years, was only on portions of the bridge, and was being removed over time. Containment was used during paint removal above land, it said.

Reller said he found there were few records for where lead-based paint was used on the bridge.

The agency said more durable paint was now used, reducing the need for repaints and sandblasting.

"These innovative environmental management solutions were recognised, with the Auckland Harbour Bridge project winning the 2015 New Zealand Planning Institute Awards, Best Practice Award for Integrated Planning and Assessment," the agency said.

"While some of the lead contamination detected in soil samples from the Te Onewa Point Reserve is likely the result of historic bridge maintenance activities, it is unlikely that those activities are a significant ongoing source of contamination."

Close to going public

In its statement to RNZ, the agency did not directly address its approach to telling residents at Stokes Point.

In the tug-of-war over the embarrassing bridge test results in 2011-12, it had come close to telling households.

Several internal reports laid out the agency's various statutory duties and internal policies that either virtually obliged it to inform people, or favoured involving them.

Consultants told it to tell residents.

Once that happened, it could get consent to test on their properties, they said.

The agency prepared a mailout, and a fact sheet, to go to about two dozen houses near the reserve in 2011.

"The decision to engage and inform Stokes Point residents is significant because of number of people impacted, high social and environmental risk, precedent effect and residual risk," Reller wrote in an April 2011 internal report.

A January 2011 report envisaged locals being told for the first time in a face-to-face on-site meeting in early February; it talks of a "duty of care to inform", and seeking "permission to sample".

The Transport Minister was expected to be told that month, it said.

Auckland Public Health encouraged going public, but at the same time can be seen in its 2011 letter trying to distance itself, to put all the onus on NZTA.

It asked the agency to remove a reference to Auckland DHB from the fact sheet, and to seek permission to use the names of the DHB or of Auckland Public Health.

The agency should set up a hotline for public enquiries and "clinical triage", Public Health said.

It should bring in an experienced doctor, plus a tester "to carry out site assessments when requested by local residents".

"Publicise your intent to introduce an abrasive and paint debris containment process, as per best overseas practice, to ensure that there is no future addition to the contaminant load already present," Public Health advised NZTA.

Instead, the agency first set up and then cancelled two "go-public" dates. At the time it was awaiting a health risk assessment by Auckland Council. More details are being sought about this.

A spreadsheet of risks shows how fraught it had become: It lists many "very high threat" risk priority items, including that soil would be contaminated further; that the agency "cannot/will not commit to containment as originally presented to" Auckland Council; and one "extreme threat" revolving around the possibility of lack of agreement, or delays around consulting, with locals.

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Reports showed soil samples from near the Auckland Harbour Bridge revealed some chemicals were above permitted levels. (File photo). Photo: 123rf

Fraught, and ultimately resolved in favour of silence.

An August 2012 report said: "The full extent of contamination derived from the AHB and the associated community exposure is unknown, because investigations to date have been restricted to the reserve."

Reller believes just two houses, perhaps, might've needed some garden soil replaced, or other remediation.

But he gave up after a half-dozen attempts; the counter-argument, he said, was that telling residents would cause alarm out-of-proportion to the risk, both locally and for other places where people live alongside highways.

This could be true, but "that's not their right, to tell somebody else that they don't have a right to know that they're under harm", Reller said.

"They didn't want - they don't want - the public involved in their business," Reller said of NZTA.

'Not a risk to human health'

Prompted by the Te Onewa/Stokes Point findings, Reller commissioned tests of soil contamination in late 2012 at three other state highway corridors in Auckland.

This short study found contamination was not too bad, and was limited to a narrow band within about 50 metres from the road.

Lead, copper and zinc exceeded permitted levels at the central motorway junction and Point Erin on the bridge's south end, while Oteha Valley bridge near Albany was fairly clear.

At the former two sites, "ecological receptors" might be at risk, but "it appears that contaminants do not pose a risk to human health".

At Te Onewa/Stokes Point, a health risk assessment by the council led to it capping some of the land, NZTA said.

The council has been approached for comment.

A further health risk assessment done by consultants for the Transport Agency, in 2013, was reassuring about lead levels at the bridge's north end.

These showed that "while there may be a few exceptions, the majority of the residential properties would likely be below the derived soil criterion for lead and therefore within acceptable health risk".

Less reassuring was the rider: "As there has been no actual investigation within the residential properties, there is significant high uncertainty with respect to the results of this assessment."

The consultant recommended more tests.

The agency's statement on Friday makes no reference to the Te Onewa/Stoke Pt residents or more testing.

Carl Reller contends that NZTA "utterly failed".

"They say that they are environmentally and socially responsible, but it's in word only. It doesn't follow through.

"During their consultations, they would say that the community would have a right to know that there's a motorway going through their neighbourhood.

"But as to the effects of that motorway, and what it would cause to them, I would say that they wouldn't be straightforward about the negative effects on the community."

The Timeline, according to documents:


  • Soil tests find contamination at north end of bridge, as part of NZTA application for first resource consents for Harbour Bridge maintenance


  • August/Sept - Soil tests as part of application to renew bridge consents find contamination above permitted levels, and rising since 2001
  • Sept - Auckland Council rejects consent application as "inadequate
  • Nov - Engineers tell NZTA the test results show "further action will be required"; agency's environment team prepares plan


  • 11 Jan - Consultant identifies potentially affected land owners
  • 19 Jan - A "go-public" date of 4 February is proposed (later cancelled); Stokes Pt community and Māori stakeholder interest listed by NZTA as "high"
  • Jan 28 - Auckland Public Health requests more investigation of effects on marine life and groundwater, lists recommendations for going public
  • Feb - Second lot of soil tests finds similar contamination
  • 4 and 15 Feb - Agency receives two internal legal opinions on the potential legal risks - from the contaminated land, and from deferring telling residents
  • March - A testing programme is cancelled as NZTA waits for an Auckland Council Health Risk Assessment
  • June - Council installs a barrier at Te Onewa Reserve around a small area contaminated with hydrocarbons
  • 31 August - Council issues new resource consents for bridge
  • Oct - An NZTA technical analysis says "residences adjacent to AHB are subject to levels above permissible limits due to their proximity"


  • Jan - New National Environmental Standard Soil Contaminant Standards for Recreation come into force
  • July - Agreement within NZTA to proceed under the umbrella of broad-scoped environmental monitoring programme
  • 18 July - A move to alert property owners by letter is cancelled
  • August - Management strategy advocates further soil tests and provides a communications plan that takes into account "if people have questions regarding their personal health"
  • Nov - Study of soil contamination at three other highway sites finds some elevated levels; concludes "contaminants do not pose a risk to human health"


  • August - Health risk assessment for NZTA concludes most of the Te Onewa/Stokes Pt homes would likely be "within acceptable health risk", but recommends more tests


  • Further soil tests as part of a walkway project; agency says these find similar contamination levels as in 2010-11.

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