Update on GDC’s DrainWise project
A recent update for councillors on the DrainWise programme aimed at reducing wastewater overflows during heavy rain said work this financial year was progressing mostly as planned, consent approval for discharges into city rivers was anticipated early next year, and that additional staff would be needed.
As always, the report said the programme might only start showing visible results towards the second half of the 2018-2028 Long Term Plan, over which the council has budgeted $26.85m for DrainWise.
The report said the project team included internal and external resources, and “sufficient resources have been available up to now”.
“Going forward, additional staff will be needed in order to roll out the remainder of the DrainWise programme (including minor fixes, investigations, and compliance and enforcement processes).”
With the council having identified that the main issues were on private property, via rainwater inflows into the wastewater system via gully traps and infiltration into broken private pipes underground, a key success factor was having property owners fix these problems — and the team was working to inspect properties and assist homeowners.
At the same time, the council was making sure public infrastructure was adequate and looking for solutions in problem areas for private properties, eg public stormwater network extensions.
Ongoing work, focused on Kaiti, included investigations of properties likely to contribute significantly to inflow issues. Newer actions included a rapid inflow assessment focused on the Seymour Rd/Turenne St catchment (with the aim of reducing inflow as much as possible before next autumn/winter), and a pilot project for the team’s infrastructure improvements on private property strategy, to be completed by February 2021. The Rutene Rd stormwater upgrade had been delayed due to Covid-19 and other unforseen issues, and was on schedule to be completed later next month with a second stage to be completed by June 2021.
The council was supposed to have resource consent for emergency wastewater discharges into the city’s rivers by July 2020. The consent was submitted in June and the project team was working with the regulator to obtain the consent as quickly as possible — with approval anticipated in the first quarter of 2021. Dry-weather overflows have been non-compliant since the Tairawhiti Resource Management Plan came into force in mid-2017.