Investing in resilient flood infrastructure

Wairoa was badly affected in Cyclone Gabrielle, resulting in over 600 properties identified as Category 2 under the Government’s land categorisation framework. A similar area was also flooded during Cyclone Bola in 1988.

As part of the cost-share agreement the Government agreed to 100% fund the capital build of a new flood mitigation solution to overcome affordability barriers experienced after Bola. We now need to decide how to rate for the ongoing operations and maintenance of the scheme.

A further option for Wairoa is to extend the indirect scheme footprint. Direct scheme beneficiaries are assessed for risk and benefit based on the flood solution; they will typically be properties flooded in Cyclone Gabrielle or likely to flood in a similar event. Indirect scheme beneficiaries are those who benefit from a more resilient township and could include Fraser Town or all of the Wairoa District Council’s boundary. Extending the indirect footprint would lower the average targeted rate shown below, and benefit properties with high capital values within the indirect footprint.

To view the tables below in PDF format, see Part 3 of our full Consultation Document.

Enhancements to the Heretaunga Plains Flood Control Scheme (HPFCS) aim to address the areas most impacted by Cyclone Gabrielle. As these improvements form part of a larger scheme, the targeted portion of the costs are shared across all existing scheme ratepayers. This results in the additional costs per scheme ratepayer being lower than the other new schemes.

In Ohiti Road, Omāhu the impacted community of 17 rateable units will become direct (as well as indirect) beneficiaries.  Pākōwhai and Waiohiki properties that will be protected by the new solutions are already direct and indirect ratepayers.

To view the tables below in PDF format, see Part 3 of our full Consultation Document.

The Whirinaki flood scheme has been split into two parts – Whirinaki (Industrial) and Whirinaki (Other).

To view the tables below in PDF format, see Part 3 of our full Consultation Document.

Whirinaki (Industrial) relates to the flood mitigations to protect the commercial/industrial activities in the area flooded during Cyclone Gabrielle up to 1 in 500-year level of service. There are four rating units in this scheme owned by Pan Pac, Transpower, and Contact Energy. These ratepayers require this protection to insure their assets and continue operating.

Another rating model for this scheme could be a greater targeted component to reflect the more direct benefit such as 90% Targeted Rate and 10% General Rate split.

Whirinaki (Other) relates to the predominately residential area covering Pohutukawa Drive which was flooded during Cyclone Gabrielle and the wider Whirinaki community who have a more indirect benefit such as road access. It’s also about retaining community.

The Regional Council agreed to consult on a specific option for Whirinaki (Other) of 50%/50% split to fund the capital build of the scheme. This would improve affordability for the small scheme footprint.

This new scheme covers the predominately residential area in Pōrangahau where flooding occurred during Cyclone Gabrielle plus the wider Pōrangahau township which has a more indirect benefit. There are four small-scale commercial or industrial properties which also fall within the footprint.

The Regional Council agreed to consult on a specific option for Pōrangahau of 100% General Rate to fund the capital build of the scheme and 50 percent/50 percent split for operating and maintenance once it is built.

The bespoke arrangement is being considered due to the small scheme footprint and socio-economic status of the area. The 100% General Rate funding of the capital build is aligned with the approach for Wairoa, who are not incurring the capital costs of the flood mitigation scheme.

In addition, the recently released NIWA flood analysis indicates that the annual return interval for an event the size of Cyclone Gabrielle is around 80 years at Pōrangahau River (noting a high level of uncertainty due to short records). This reinforces the need for appropriate flood protection for this community to reduce the risk of future flooding, which will increase with a changing climate.

To view the tables below in PDF format, see Part 3 of our full Consultation Document.