Environmental standards for new septic tanks - December 2021

If you are applying to install a new septic tank or onsite wastewater system, you should be aware of the environmental standards required to look after the health of our waterways and drinking water. Read the information below to understand what you need to know to apply.

You need to show that you are installing the right system for your site and how it will protect local water quality and ensure safe drinking water for neighbours.

A higher-standard system may increase your costs but is also likely to provide a better environmental outcome for your property and neighbouring waterbodies, including drinking water.

What septic tank/onsite wastewater applications are likely to undergo a more detailed review process?

All applications are assessed on a case-by-case basis but, in general, detailed information and proof of plans for highly-effective systems will be required for:

  • Sites smaller than 4 ha;
  • Properties with no reticulated sewers or water and where groundwater is shallow;
  • Areas with known high levels of nitrate and E. Coli in the groundwater;
  • Where groundwater is shallow and there are properties with drinking-water bores located near or down gradient from the proposed site;
  • Properties within a Community Drinking-Water Supply Protection Zone.

Why is the process more rigorous for some applications?

More detailed plans are required when science shows water quality in an area is at risk from high nitrate and E. Coli levels.

In terms of legislation, our decisions on consents are guided by the National policy statement for freshwater management (NPS-FM)  and the National Environmental Standards for Freshwater (NES-F) as well as our Land and Water Regional Plan and the principles of Te Mana o te Wai, which prioritises the health and well-being of freshwater.

What’s the environmental concern?

Discharge containing contaminants from inadequate onsite wastewater systems could end up in nearby domestic drinking-water systems and make people sick. Poorly treated discharge can also pollute nearby streams and waterways.

Read relevant scientific information about groundwater in Canterbury

What guidance is available to help me understand the septic tank/ onsite wastewater system consent application process?

Environment Canterbury is developing an updated tool to assist with assessing appropriate areas for onsite waste management systems and a detailed technical factsheet to help with consent applications.

In the meantime, contact our customer services team on 0800 324 636, who can give you current advice.

What if I already have a septic tank system installed? Do I need to upgrade it?

No – not unless you have a consent that expires or there’s a problem with your system’s operation.

What is Environment Canterbury doing about other contributors to pathogens aside from wastewater, like farming activity and industry?

Over the past 10 years, the Canterbury Water Management Strategy, Canterbury Land and Water Regional Plan, and its later, sub-regional updates have started to address the problems caused by land-use intensification. 

Some of the impacts of these new rules are only starting to take effect, and there is a lot of work to be done by farmers, industry and Environment Canterbury in coming years. 

The National Environmental Standards for Freshwater (NES-F) – a key aspect of the Essential Freshwater package - means more consents for more farmers, as some activities that were previously permitted will now require consent.

Additionally, the central government is proposing to make it mandatory for all farms above 20 hectares to have a freshwater module in their farm plan, which will need to be in line with catchment-specific freshwater objectives.

If you have any further questions, contact customer services on 0800 324 636.