The DrainWise project is about working together with property owners to help fix problems with wastewater and stormwater drains.

Too much stormwater is still getting into our wastewater network during heavy rain. This causes wastewater (sewage) overflows into our rivers and the sea. The main cause is illegal spouting connections and broken gully traps on private properties.

Our DrainWise programme launched in 2016, aims to reduce wastewater overflows onto properties and into our city's rivers.

In the 2018-2028 Long Term Plan we consulted on how we should approach the issue of reducing inflow and infiltration of rainwater into the wastewater system.

Submitters supported Council’s preferred solution that will focus on replacing 54km of old wastewater pipes in the public network over the next 30 years, and investing $6m towards improving stormwater drainage on private properties that are the worst contributors to the problem.

The programme is progressing well and will continue into the 2021-2031 LTP as planned, as we still need to do more to stop the overflows.

In addition to public works, the programme requires property owners to fix problems with their wastewater and stormwater drains to stop rainwater flowing into sewer pipes.

Half of the city’s wastewater pipes are on private property and because they belong to homeowners, the responsibility lies with them to ensure they don’t leak.

Council inspections of these underground private pipes have shown that about half are in a poor condition and leaking.

When these pipes leak, they let rainfall into the sewage system which then struggles to cope, leading to overflows during heavy rains.

Ensuring the privately-owned underground sewage system isn’t leaking will help reduce overflows.

We’ll continue to work with property owners to inspect and assist homeowners and educate residents about fixing issues with gully traps, downpipes and underground pipes in their homes.

The programme consists of a number of projects, the main components are:

  • stormwater network upgrades and renewals
  • wastewater network upgrades and renewals
  • public drains on private property (stormwater public network extensions into privately-owned land)
  • property inspections with the primary focus in Kaiti, followed by Whataupoko, Elgin and the rest of the city
  • educating the community and raising awareness
  • roll out of compliance and enforcement
  • continue with minor public-funded works on properties

What we've requested in the 2021-2031 Long Term Plan

Additional capital expenditure has been requested in the 2021-2031 LTP to increase emergency storage at pump stations and progress renewal of wastewater pipes faster than planned.

A consent application for wet and dry weather wastewater overflows was also submitted in June 2020.

We continue to carry out property inspections, including detailed investigations as well as more focussed investigations (such as the rapid inflow assessments).

This work is being undertaken as part of Council’s role in providing advice to homeowners, and to feed into compliance and enforcement processes.

We’ll also continue with CCTV investigations and smoke-testing to identify connections between stormwater and wastewater, and remedy these, or ask homeowners to implement the fixes.

The team has also established a Drainlayers Forum and a Property Managers Forum, which will be used to get buy-in and support from these key influencers in Tairāwhiti.

These forums, in addition to improved drainage data in Land Information Memoranda (LIMs), will enable improvements to also be driven from within the private sector.

  • $4.1m capital expenditure is forecast for work on private property and $5.4m will be spent upgrading the stormwater network in priority catchments.
  • Operational budgets for DrainWise (including water supply and stormwater budgets) are $3.8m over the 2021-2031 LTP.

The project is 100% Council funded. We’ll take on debt to fund the work each year, and increase rates to pay it back over time. We’ll also continue to look for alternative funding to do more.

Keep stormwater and wastewater separate