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What we've done

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What we've done

Council has been working to reduce wastewater overflows in the Gisborne urban area since 1982 in the Gisborne City Council days. Assets & Infrastructure Committee Report 17-430 [PDF, 216 KB]

We have largely focused on the public (Council-owned) stormwater and wastewater networks by;

  • Increasing the size of Council’s wastewater pipes where they are under capacity,
  • Upgrading the stormwater network to manage larger flood events,
  • Replacing Council’s leaking wastewater pipes and access points,

This has all been done to reduce how much rainwater gets into the wastewater system.

But it is important to remember that Council only owns 50% of the network.  The other half of the network is on private property. Property owners are responsible for the management and maintenance of the wastewater and stormwater system within their property boundaries.


Even though we have done a lot of work on our networks, overflows are still occurring. This means that even after working actively for two decades to fix the public half of the networks, the reduction of rainwater into the wastewater system is still not enough.  The number of wastewater overflow points and quantity of wastewater has been reduced but not the number of events (maximum of four per year).


Through extensive study, we now know that private property drainage has one of the highest impacts on the performance of the public wastewater network. In acknowledgement of this, we recognise that fixing on-property flooding is a fundamental infrastructure problem and prioritised solving this issue

Future Tairāwhiti Committee Report 17418 [PDF, 232 KB].


We have recognised that stopping rainwater getting into private wastewater systems is key to solving the issue.To address this private property issue, Council launched its DrainWise Wastewater Discharge Reduction Plan in 2016

Wastewater Discharge Reduction Plan [PDF, 1.6 MB]


There are a number of people working on the DrainWise plan which comprises of a number of projects and tasks that address the issue described above.Visit our “what we're doing” page to learn more about how we are implementing the DrainWise programme of works.

What we're doing


For more information about what we’ve done, check out the documents below. You can find these by simply entering the report title or reference number into the keyword field of our online meetings reports search;

Assets Infrastructure Agenda – June 2019

Wastewater Management COMBINED – May 2019

19/168 = DrainWise Progress Report – May 2019

15/246 = Discharges Reduction Project - Progress Update July 2015

16-006 = Wastewater Discharges Reduction Workshop One - What is the Problem? January 2016

15/083 = Wastewater Discharges Project Update and Site Inspections - March 2015

15/486 = Wastewater Discharge Reduction Programme Update - December 2015

16-304 = Wastewater Discharge Reduction Plan - July 2016

16-253 = Wastewater Discharge Reduction Programme Strategy Update - June 2016

16-068 = Wastewater Discharge Reduction - Workshop 2 March 2016