Cleaning up waterways – naturally

  • Dr Louise Weaver (ESR) and Joseph Thomas (Tasman District Council)

    Dr Louise Weaver (ESR) and Joseph Thomas (Tasman District Council) take samples of the groundwater ecosystem.

The unsung heroes of our groundwater system – bacteria and tiny invertebrates that filter out contaminants – could hold the key to helping clean up our waterways.

Researchers from BioHeritage Challenge Parties NIWA, ESR and Waikato University are looking at how the microbes living in underground aquifers help to keep groundwater supplies healthy. Once fully understood, these organisms could be introduced to specific waterways to help clean them up.

The work is being led by NIWA’s Dr Graham Fenwick and ESR’s Dr Louise Weaver. Louise says the ecosystem in groundwater plays a vital role in processing contaminants, such as nitrates, that end up there from a range of land uses.

In this ground-breaking research, the scientists are starting to build a picture of the array of organisms present in groundwater.

“If we understand the processes and the organisms involved in more detail then there’s the potential to actually use them for bio-remediation. In the future, you could put some of these organisms into the system to drive the removal of contaminants even further.”

“At the moment, there’s so much fundamental information we don’t have. There’s a whole range of organisms that have specific functions, habitats and inter-relationships, which are currently poorly understood.”

This work is part of wider, aligned research that is funded through ESR’s Strategic Science Investment Fund (SSIF). The SSIF project aims to develop an index, similar to the macroinvertebrate community index which is used in surface water, to get an indication of the health of the groundwater resource.

New Zealand scientists are at a very early stage of developing that groundwater index, and refining systems for getting accurate samples of the vast array of macroinvertebrates and microbial organisms that are there, Louise says.

Read more about the project.