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Dairy Effluent Conversion Project

About the project DECP3

The Dairy Effluent Conversion Project is trialing the conversion of waste nutrients from dairy effluent into algae and zooplankton that can be used to feed fish.

If it succeeds, the project expects to see improved water quality leaving the drainage system and improved numbers of species such as tuna (eel), inanga (whitebait), and mullet.

The three-year trial is taking place on an operational dairy farm near Katikati.

We recently held a public open day in conjunction with DairyNZ to show the trial site and explain the initiative's goals.

You can see a few photos from the day below and read the media releases.

And featured on TVNZ's Rural Delivery programme on 10 September 2016.

Who is involved in the Project?

BOPRC logo Bay of Plenty Regional Council Joint funder, project management, resource consent monitoring
MPI logo Ministry for Primary Industries Sustainable Farming Fund Joint funder through the Sustainable Farming Fund
  Landowners and sharemilkers Project support, provision land and dairy shed effluent required to undertake the trial, access for the project team, and daily site checking.
NIWA logo NIWA Project support – design and operation of the High Rate Algal Ponds and Algal Harvest Ponds, project monitoring
Raglan Eels Logo Raglan EELS Project support – design of zooplankton pond including aeration devices and level control structures
BOP Polytec logo Bay of Plenty Polytechnic Project support – monitoring programme

Read more about the project and the Bright Ideas Innovation Fund in the August 2015 update to Council Committee

Check out the step-by-step photo explanation of the project

Click on the image below for a larger version

DECP photo explanation (small) 










Photos from the Open Day, February 2016

Open day 1 

Thanks to the landowners and sharemilkers who made us feel welcome for the open day. 

 open day 2

We broke into smaller groups and had a look around a few of the key project sites. In front of this group are the High Rate Algal Ponds (HRAPs) and behind are the Algal Harvest Ponds (AHPs)  

 open day 3

One of the groups having a chat near the HRAPs. 

 open day 4

The paddlewheels keep the effluent from the dairy shed circulating around the ponds promoting growth of the right algae. 

 open day 5

An existing farm drain was cleared and widened to create the zooplankton pond.

 open day 6

One of the groups having a chat alongside the zooplankton pond. 

 open day 7

Afterwards, we had a de-brief and a great question and answer session. 

 open day 8

There was some good 'blue-sky thinking' about where this technology could lead and the potential flow-on benefits for farmers.


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