A Northland iwi leader is calling for Covid-19 wastewater testing to happen immediately in future lockdowns as regional investigations ramp up.
The Whangārei district water testing laboratory at Whangārei's Kioereroa wastewater treatment plant, which serves about 70,000 people. Photo: Michael Cunningham/Northern Advocate
Anahera Herbert-Graves, Te Rūnanga-a-Iwi o Ngāti Kahu chief executive, said the roll-out of Covid-19 wastewater testing had been too slow.
It should have started as soon as a lockdown happened and national systems for starting the testing as soon as any lockdown was announced should now be put in place, she Herbert-Graves added.
Northland has this week had one of New Zealand's biggest regional Covid-19 wasterwater surveillance efforts. Eighty-five per cent of the region's 32 wastewater treatment plants are now on the books for being tested for the virus - up from 15 per cent at the start of the week.
Herbert-Graves said the increased testing was good to see, but it should have swung into action much sooner, at the time lockdown was put in place.
Her comments came on the eve of expected results from the ramped-up testing coming closer to being released.
New Institute of Environmental Science and Research (ESR) results released yesterday show the virus has not been detected in 20 Northland wastewater treatment plants analysed to date.
Ngāti Kahu is part of Te Kahu o Taonui, the Northland Iwi Chairs Forum, which this week called for the testing to be ramped up across the region.
At that stage, it was being done in five of Northland's 32 wastewater treatment plants (WWTP)s - Whangārei, Kerikeri, Kaitaia, Paihia and Rawene.
Testing is now happening at 28 of the region's 32 WWTPs.
In the Far North (19 WWTP)s that is at Ahipara, Awanui, Hāruru, Hihi, Houhora, Kaeo, Kaikohe, Kaitaia, Kawakawa, Kerikeri, Kohukohu, Opononi, Paihia, Rangiputa, Rawene, Russell, Taipā/East Coast, Whangaroa and Whatuwhiwhi.
In Whangārei (nine WWTP)s testing is being done at Whangārei - (Kioreroa) with Oakura, Ruakaka, Tutukaka and Waipū soon to be added. Hikurangi, Portland, Ngunguru and Waiotira are not being tested.
In Kaipara (four WWTP)s that is at Dargaville, Kaiwaka, Mangawhai, Maungaturoto.
No testing was done in Kaipara at the start of the week, in spite of it being immediately next door to Auckland - the current Delta community outbreak's epicentre.
Covid-19 wastewater testing has yet to start but is planned for Whangārei district's Oakura, Ruakaka, Tutukaka and Waipū WWTPs.
Yesterday's ESR results for this week to date show the virus has not been detected in 18 Northland wastewater treatment plants so far analysed - Ahipara, Awanui, Hāruru, Hihi, Houhora, Kaeo, Kaikohe, Kaitaia, Kawakawa, Kerikeri, Opononi, Paihia, Rangiputa, Rawene, Russell, Taipā, Whangārei and Whatuwhiwhi.
Herbert-Graves said the obvious influx of Auckland bach owners into Northland as New Zealand's national level 4 lockdown was put in place meant testing wastewater for the virus was critically important.
This became even more so with the large number of Auckland Delta outbreak close contacts.
Huhana Lyndon, Ngātiwai Trust Board chief executive, said Covid-19 wastewater testing helped provide reassurance around whether the virus was locally present.
Herbert-Graves said this was clearly borne out by Warkworth's positive Covid-19 wastewater test being followed by the discovery of a positive Covid-19 case in the town.
Lois Howe, Whangārei District Council (WDC) laboratory manager, said the council had been sending raw sewage from its Kioreroa plant twice weekly to Wellington for Covid-19 testing.
The plant serves about 70,000 people, roughly 70 per cent of Whangārei district.
Howe said Whangārei district WWTP Covid-19 testing was initially done only at this plant, because at first only bigger plants were being monitored.
The surveillance programme had now been expanded to sample raw sewage from reticulated sewage schemes in Whangārei's coastal settlements.
Howe said the ultra-sensitive test could detect the distinct RNA strands shed by people carrying the virus. The results were used to alert Government to the virus' presence in the community, even where cases had not been identified through individual medical tests.
WDC has been Covid-19 testing since early July. WDC's WWTPs are not being tested.
Covid-19 wastewater testing is set up by the Ministry of Health with the Institute of Environmental Science and Research (ESR) analysing surveillance samples.
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