A brassy hot February afternoon and I’m visiting the contentious Central Hawke’s Bay ‘poo ponds’ to find out why they are failing to turn the district’s sewerage into a discharge that leaves the Tukuki safe for downstream swimmers and critters.
That’s the goal, but the alchemy is yet to work, with the ponds falling well short of their legal requirements to filter out toxic soluble reactive phosphorous, ammoniacal nitrogen and E.coli before discharging into the Waipawa and Tukituki rivers. On 26 January the Hawke’s Bay Regional Council put the CHB District Council on notice, issuing ‘cease and fix’ plans to be ticked by July/August.
I meet up with Steve Thrush, engineer for CHBDC and man in charge, at the Waipawa wastewater site. It’s almost scenic: a small dark lake framed by mountains in the distance. There’s barely a whiff in the air.
Thrush is patient and keen to walk me through the process.
He points out a filter by the entrance which sifts out the solids for landfill before the rest flows into the holding ponds, where ideally it circulates for 30-50 days (in reality 20) being worked over by up to 3,000 species of bugs. A floating bed of native reeds acts as a filtration system, drawing up the last of the nitrogen before the water is dosed with chemicals to bind the phosphorous to then be (theoretically) separated out by sophisticated sand filters. What should at this stage be clear water is lastly treated by UV light to remove all pathogens before being discharged via a bush drain to the river.
The UV treatment only works, however, if particles in the water are less than 5mg/ml, which is not the case now, so it’s currently only working at 30% capacity. The sand filter is not filtering properly. It’s clogged by a sludge of phosphorous and chemicals that have not bound in the way they should, in part because tannins are interfering with the process.
But where the tannins come from, and how to deal with them at source, has yet to be identified.
It could be that Waipawa residents drink inordinate quantities of tea. But a more likely explanation is the two local trucking firms hosing off effluent into the drain or the 40-year-old pipe that’s potentially cracked and leaching in tannins from the peaty surrounds. Thrush says they are working with Massey University to investigate.
In the meantime, to solve the problem of phosphorous, they’re trialling different chemicals to find a more effective, stronger mix that won’t react with tannin, and have ordered new and repurposed clarifying units to mechanically settle out the floc, the “light, fluffy stuff” that’s stuffing up the system. CHBDC has also engaged an expert firm in Auckland, with experience with similar systems overseas, to help deal with the ongoing issues.
It all sounds pretty experimental, however, and late in the piece to be tinkering. The Waipukurau plant – same design, larger scale – was only completed in September last year, just weeks before new discharge standards came into effect. The floating wetlands require time to ‘bed in’ and they’re still sorting out adequate aeration.
Thrush concedes it’s been an unfortunate play of trial and error; “we thought we were buying something that had a proven track record.” Both wastewater systems are modelled on a similar plant in Hunterville that was producing drinking-quality water at the time, says Thrush, but has since run into similar difficulties with phosphorous. Initial results from the Waipawa plant (completed 2013) were promising, and here the floating wetlands at least appear effective in dealing with nitrogen and bacteria.
Thrush says he’s been taking samples from the river both upstream and downstream from the outlets “to see what effect we’re having, and basically there’s no difference between the samples.” While he’s as keen as anyone to get the discharge levels right, and better, he refutes the claim that CHBDC are “polluting the river”.
A ‘second-best’ scheme?
But it’s been over a decade since the effluent ponds in CHB, which were discharging raw sewerage straight into the rivers, were identified as a major problem, and environmentalists such as John Scott, who’s been fishing the Tukituki for 45 years, are frustrated the issue has still not been resolved, despite the legal battles, the countless discussions, promises and missed opportunities.
Since 2006 when resource consents for Waipawa and Waipukurau were issued following an Environment Court process that stipulated more rigorous conditions, CHBDC knew the discharge standards they would have to meet by 30 September 2014. But it took six years alone to decide on a wastewater system.
They initially considered a dual-discharge approach, which would have seen over half the waste discharged onto forested land, bypassing the river altogether. The regional council actively championed the proposal, and in 2010 even purchased land for $1.6 million expecting in ‘good faith’ that it would be used for this express purpose.
However, in 2012, CHBDC decided not to run with the scheme after all, as it was looking to cost more than the $8.6 million they had budgeted for and they faced a potentially costly hearing process with challenges to the proposal as it stood.
Concerns that would need to be addressed included the observation that the land purchased was neither large enough to cope with the quantities of effluent nor the appropriate soil type; the possibility of sodium land-contamination; and the fact that 40% of the wastewater would still be going into the rivers.
HBRC still maintains that a dual-discharge or discharge-to-land type approach is the preferable option with a better outcome for the river, but in the end it is up to the district council.
Thrush is unapologetic over fiscal decisions. “We have a small population, many on fixed or low incomes and our ratepayers include communities such Porangahau who are not connected to the system. We work within a very limited budget.”
CHB District Council looked at five alternatives, including worms and other on-land biosystem treatments, but the floating wetlands option stacked up well as cost-effective, simple and “a good system if it runs properly”. The catch, of course, is ‘if’.
John Scott believes HBRC should have funded the difference between what CHBDC could afford and what was needed to do the job properly. “The Tuki is not a CHB problem, it’s a Hawke’s Bay problem – it’s an iconic river that flows through our region, and this affects everyone along the tributary from Waipukurau to the Haumoana estuary.”
But in advocating for the Tukituki over the last 10+ years, Scott says he has experienced a systemic unwillingness among regional council staff to listen to anyone outside the closed walls of office and influence, to the detriment of the river and genuine progress. He cites numerous examples where environmentalists’ concerns or recommendations have been ignored.
For instance, two years ago, when they were finalising plans for the wastewater plants, HBRC consultants met with environment groups to discuss their intention to reduce the size of the holding ponds in an effort to reduce the cost CHB had to meet. “We argued that by making the ponds smaller, they reduce the window of opportunity to deal effectively with overload, such as stormwater; they’ll be forced to dump excess when it doesn’t suit the river flows, as has happened now. But council didn’t listen, and signed off the plans for smaller ponds.”
“It was an apology for consultation, it always is—the council has a pre-ordained outcome for what they want to do, and consulting with us is simply a process they have to go through to tick the boxes.”
So now what?
Scott believes HBRC have been too lenient on the district council (“they need CHB for the dam”), and that their decision not to prosecute in this instance bodes poorly for land intensification conditions under Plan Change 6 that will be even harder to regulate.
“The HBRC has got no track record of enforcing consents if they are broken. If the Ruataniwha dam goes ahead and there are farmers not meeting the quite stringent run-off levels set, what faith can we have that the council will enforce compliance? As the regulatory body, the regional council has a responsibility to maintain and enhance our rivers, but they are not even upholding their basic duty. If they can’t enforce compliance, they shouldn’t be issuing consents.”
A few days later, I am sitting down at the regional council headquarters with Iain Maxwell, resource group manager, Charlotte Drury, principal consents officer, and Wayne Wright, compliance manager.
They clarify that the consents for the wastewater plants effectively set the outcome (the discharge standards) but it was always up to CHBDC to “figure out how to get there.” Drury: “And that’s the RMA. It’s not our role as the regulator to tell someone how to achieve something; it’s our role to set the standards necessary to ensure that the environment is protected.”
But all three are careful to stress that they are working collaboratively with the CHB District Council on the best course of action, and have been in close communication all along.
“It’s not like we just sat there and watched the train wreck”, says Maxwell.
Wright explains: “We identified early on in the monitoring process that we were [potentially] going to be in trouble…. CHB were doing all they could to try and make it work and the whole time we were trying to impress upon them how important it was to get it right.”
After the new discharge standards came into effect, six consecutive samples showed the Waipawa plant discharge exceeding acceptable levels of phosphorous, and Waipukurau exceeding on phosphorous, nitrogen and E.coli. When the latest results came in on 4 January, both plants were officially deemed noncompliant.
HBRC chose to take the route of issuing CHBDC with abatement notices, specifying what needs to happen and when before 8 July (Waipawa) and 19 August (Waipukuruau) respectively.
Iain Maxwell disagrees that HBRC should have prosecuted. “If CHBDC were turning around and saying, ‘we don’t think there’s a problem, you guys are being difficult’, then we might have to take a more coercive approach. But that’s not the case. We have a willing participant, agreement on the outcome, a plan in place. We’d rather have CHB invest their money and energy into achieving that outcome, buying the equipment, putting in the extra infrastructure, than fighting us in court over something they agree with anyway. What a nonsense that would be!”
Wayne Wright says an abatement notice is “a serious and significant legal document”, it’s not simply an extension. And while he doesn’t want to pre-empt what course of action HBRC will take if CHBDC fails to address the conditions within the timeframe laid out, he emphasises that “our expectations for meeting the discharge standards won’t have changed, and all options, including stronger enforcement tools, remain open.”
While the likes of Steve Thrush at CHBDC work hard to find effective solutions for a wastewater system that is still to be proven, HBRC stands with hand poised on the whip urging them on.
If consent conditions have still not been met come August despite all intentions, and HBRC don’t prosecute CHB council, the environmental protection group, Friends of the Tukituki, will be engaging in a legal battle to bring them both to task. They have threatened to take CHBDC to court for “continuing to pollute the Tukituki and HBRC for not fulfilling its statutory obligations”.
Meantime, the Otane oxidisation pond, whose discharges also wind up in the Tukituki, will soon further complicate the situation. Its consent expires 30 September this year. What contingency has been made for this, or will we see a replay of process?
HBRC say they’re already in discussion with CHBDC, who have been working with HBRC scientists and the Papanui Working Group on the Otane situation for some time. A proposal will be lodged mid-year and HBRC will decide then if the Otane pond needs to be upgraded. If yes, under Plan Change 6 the CHBDC will need to inform HBRC of their upgrade system at the time of consent application.
The Tukituki awaits its cleansing!