Lifting the lid on Havelock North’s water supply

Lifting the lid on Havelock North’s water supply

The water supply contamination that recently plagued Havelock North clearly shows our towns have work to do to ensure domestic water supply is safe. While a public inquiry investigates what caused the campylobacter contamination, what we can be certain of is that it was not the result of intensive agriculture.

What we do know is that this isn’t the first time Havelock North’s water supply has been contaminated. A 1998 report details an earlier contamination of the same Brookvale Road wells and concludes that contamination was very likely due to the poor design of the water supply bore and insecure well head (see supplied graphics).

The head of the well is below ground level and is not adequately protected – it allows contaminated water to flow into it during flood events. The concern is we’re now 18 years on and the same incident has once again occurred, this time with far greater consequences. Evidence that will be presented to the government inquiry shows the bore is now badly corroded and there are cracks in the casing.

It seems Havelock North has been caught in a perfect ‘storm’. Water infrastructure that is at the end of its serviceable life (common in many New Zealand towns and cities); a dramatic weather event that has resulted in surface flooding directly into the bore – contaminating the water in the well around the pump (not the aquifer); and an extended power outage meaning the pump - meant to remove dirty flood water around the bore - failed.

This example shows we have a long way to go to ensure drinking water supply is well managed in New Zealand. The question is how many more Havelock North’s are out there?

There have been misleading and alarmist claims by the anti-farming lobby that the aquifer itself has been contaminated by intensive agriculture. This is completely untrue and here’s why.

Surrounding bores that draw from the same aquifer have been tested and show no contamination – the aquifer is not polluted.

Any Hawke’s Bay resident will tell you there is no intensive livestock agriculture in the area – in fact the closest dairy farm is more than 40km away. There were however spring lambs grazing in the paddock opposite the bores.

Stock walking around a paddock doesn’t cause this sort of contamination. Campylobacter from livestock does not move down through the soil to contaminate aquifers – the soil provides a natural filter.

This contamination is the result of surface water directly entering the well because of inadequate infrastructure.

Quality asset management for public water supplies, wastewater and storm water infrastructure is a huge challenge for New Zealand’s towns and cities who are already facing significant cost increases. Council’s only source of significant income is from rates. While the question must be asked as to why Havelock North’s water supply bores were not adequately designed and maintained for the type of event they have recently experienced, we need to acknowledge that our district councils are struggling to fund infrastructure upgrades as more pressure results from tourism and general population growth.

Rural land users are also being challenged with significant and costly changes to way we are able to farm. These new farm practices are aimed to limit nutrient leaching and runoff. Regional councils up and down the country are putting in place limits and community expectations for managing water quality in their catchments.

Irrigated farmers are in the spotlight and tough requirements are in place, inevitably there will be more to come. Farmers are getting on and planning for this and so too must our towns and cities because we all have a role to play. Water quality is an emotive issue but we all want the same thing – healthy rivers and streams, safe water to drink and thriving regions.

Hugh Ritchie is cropping farmer who dutifully maintains three private irrigation bores on his Hawke’s Bay farm. He is a board member of IrrigationNZ and the Foundation for Arable Research. He is also former board member and water spokesperson for Federated Farmers of New Zealand.

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