Decision 7 - A solution for reducing sewage sludge and waste
Consultation has concluded
Much of our waste at the Southern Landfill is wastewater (sewage) sludge - about a quarter of the waste entering the landfill.
We actually need other waste to mix it with, so until we do something different with sludge, the landfill will grow at a faster rate than we’d like. We want to reduce carbon emissions and waste by a third. Minimising sludge is the first step.
What's the background to this decision?
Through our Te Atakura: First to Zero plan and our Regional Waste Minimisation and Management Plan
We need to break the link between the Southern Landfill and wastewater sludge and stop pumping sludge across the city, as 2020 highlighted the serious resilience issues and the significant consequences of failure.
There are four options
Option 1: No change in current practice | Option 2: Invest in technology at Southern Landfill | Option 3: Sludge minimisation through Council funding | Option 4: Sludge minimisation through alternate funding (preferred) | |||
The cheapest course of action would be to keep pumping raw wastewater across the city and disposing of it in the landfill. This is a feasible and affordable choice. | We could invest in better infrastructure at the Southern Landfill. For example, we could install a thermal drier (estimated additional total expenditure around $86-134m) and this would go some way to reducing the volume of sludge to be disposed. This option reduces some of the sludge volume to landfill, but leaves a significant remaining volume of sludge to be disposed of at the landfill. In addition, the pumping of sewage across the city would continue. | In option 3 we Invest in the existing wastewater treatment plant site at Moa Point. It would mean that sludge would not need to be pumped to the Southern Landfill and would help the city meet its environmental objectives. Option 3 would be a long-term investment that would better reflect our aspirations on carbon and waste reduction. | Option 4 delivers the same service and benefits as Option 3. However, this option is our preferred option, because the cost of the project will be delivered and funded through an external fund enabled by the Infrastructure Funding and Financing Act 2020 It means that the project would not be funded by Council debt and we would not exceed our debt-to-income cap as in Option 3. The same asset will still be constructed as Option 3 (at a value of $147m-$208m) | |||
Capital cost and debt impact: No change | Capital cost and debt impact: $86m to $134m | Capital cost and debt impact: $147m to $208m in first 10 years | Capital cost and debt impact: Same as Option 3, but through alternate funding, so no cost to Council. | |||
Rates change: None | Rates change: 0.39% 3 year average increase | Rates change: 1.65% 3 year average increase | Rates change: None, but a levy of approx. $70 to $100 per residential ratepayer collected per year from year 4 |
These options have pros and cons, and are outlined in more detail here
Our preferred option
The Council prefers Option 4, Sludge minimisation through alternate funding. Reducing carbon emissions and reducing waste by a third. Minimising wastewater sludge and reducing waste by a third is a required first step to achieving both Te Atakura (zero carbon plan) objectives and the Regional Waste Minimisation and Management Plan.
Note: Our external Auditors have made specific comment on the sewage sludge decision in their opinion in the consultation document - see pages 72-74 of the consultation document available at the link below.
Want to know more about another Decision? Head back to our Long-term Plan homepage or read our full consultation document
Or, are you ready to have your say? Head to our Long-term Plan submission form
Do you have a questions on reducing sludge and waste?
Check the FAQ's above on the right of this page as well as other questions below - your question may already have an answer.
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