We want to address and resolve surface flooding at sites in Christchurch and Banks Peninsula that experience regular issues.
To achieve this, the Surface Reduction Programme has been established, with $20 million allocated each year from July 2026 to support sites selected according to a priority criteria. Preparation work is underway to find projects that can start in mid-2026.
It’s important to note that not all flood issue areas will be able to be addressed within the programme. Additionally, where work is carried out, surface flooding may be reduced but not necessarily removed completely. Existing operational and regulatory processes will be used to manage any remaining residual flood risk.
Prioritisation work
The top flooding issues in the city and across Banks Peninsula were identified and assessed using a matrix developed to prioritise where work should be carried out first.
This prioritisation matrix was developed in collaboration with elected members. Two Council workshops were held in February(external link) and June(external link) 2025. Staff used the matrix to create three indicative flood issue area groups or tranches to be considered under the programme.
The first group focuses on quick wins based on previous investigation and design work that has been carried out for these areas. It also includes three areas where Waka Kotahi NZ Transport Association funding is available.
These tranches are being worked through one by one and issues are being investigated to see if there is a viable project, using the following criteria:
- Responsibility: Is the issue the Council’s responsibility?
- Cost: Is the cost/benefit of the solution acceptable?
- Effectiveness: Will the option effectively address risks and vulnerabilities of the area?
- Feasibility: Are there legal, technical or other requirements that present significant implementation barriers?
- Environmental: Are the environmental impacts acceptable?
- Alignment: Does the project align with other Council initiatives?
Consideration is being given to the Council’s Coastal hazards adaptation planning programme. Staff are working together to see how these programmes will integrate.
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*Potential alignment with transport works.
The Council approved the first four projects in the programme at its 3 September 2025 meeting. The projects have a cost estimate of $11.4 million and include:
- A new pump station is to be built at the Flockton Street area to replace the current temporary arrangement.
- Additional controls are to be added to the Bells Creek pump station, as well as raising land levels to help with overland water flow.
- Stormwater network upgrades at Greenpark Street.
- A diversion stormwater upgrade and new pipe network at Emmet Orcades.
Detailed design work for the four projects will be carried out in 2026 to enable on-site works to begin in 2027, as set out in the Long Term Plan. Its expected costs may vary from the initial estimates given as requirements are understood more fully following design work.
Other projects
Investigations will continue for less immediate projects. These will be progressed throughout the remainder of 2025 and through 2026. Any resulting projects will be considered as part of future annual plans.
If an area is investigated but a viable project is not identified, this will not be pursued further under the Surface Flooding Reduction Programme. Additional areas outside of the first three tranches may be investigated if there is sufficient programme budget.
Consenting requirements
There is the potential that projects may need to be deferred until later in the programme if there are issues with securing approvals and consents.