Room for improvement’ of groundwater bores across the Horizons Region

National groundwater monitoring results published by the Land, Air, Water Aotearoa (LAWA) project last week have prompted Horizons Regional Council to remind landowners to check that their wells are secure.

Horizons groundwater scientist Stephen Collins said that the national results show the Horizons Region ranks in the middle of the country in terms of groundwater quality.

“We generally have good groundwater quality around the region, but we acknowledge there are also hot spots for nitrate and occasionally other contaminants

“Where we have long-term trends available, these often show improving trends. However, there is definitely room for improvement in the general condition of bores that we see around the region”, says Mr Collins

Horizons has implemented a programme surveying wells and carrying out wellhead security assessments across the region. The assessment included a visual inspection of the well and its current set-up. 

“Unsecure wells represent a potential pathway for pathogens such as E. coli to enter groundwater from the surface, posing a risk to surrounding drinking water supplies,” says Mr Collins.

Potential points of entry to groundwater from a well can be from down the sides of the well casing or openings in the wellhead itself. Contaminants that enter a well can travel through groundwater, and other wells can draw these up.

“To mitigate this risk, landowners can ensure there is a sloping concrete pad around the base of the bore and that the well head is completely sealed from the outside”, says Mr Collins.

“People who consume untreated water from a contaminated well could become very ill. So it’s important that Horizons works with owners to ensure they are aware of the risks and how to mitigate them.

If landowners have any questions or concerns about the security of their wellhead, they can email groundwater@horizons.govt.nz or call freephone 0508 800 800, and Horizons will arrange a site visit.