Coastal Flooding and Erosion – There is a Plan

But Councils need to commit funds to implement the plan

The January 5 storm surge has underscored the urgent need for our Regional and District councils to tackle coastal hazard planning. Fortunately, our councils have some good plans to follow, and they don’t have to start from scratch.  But they DO have to commit funds for this vital work to be done.

The latest Ministry for the Environment Guidance on Coastal Hazards sets out a comprehensive 10-point plan for councils to follow when helping local communities adapt to climate change and sea level rise.  In Hawkes Bay, they have been implementing this plan for over 2 years.

Locally there are encouraging signs.  TCDC and Regional Council have begun discussions at a staff level about adopting a similar approach to Hawkes Bay.  TCDC has adopted the Guidance assumptions on sea level rise into its Long-Term Plan and has identified coastal hazards as a potential issue for funding in that Plan. 

Why is the Hawkes Bay experience such a valuable example for our councils to follow?

In 2015 the three Hawke’s Bay councils jointly agreed on functions and cost sharing for their coastal hazard strategy.  They formed a group of Council staff, consultants and community stakeholders to address the twin threats of coastal inundation/erosion.

The group has worked through three stages –

  • First, they engaged coastal hazard experts to define the locations most at risk.  
  • Second, they used the Guidance decision-making process that reflects the latest science, risks, response options, values and costs –including lay representatives of the community together with required experts.
  • Third, they identified preferred options to be tested with the broader public and elected officials.

Decision making process HB

Several possible solutions for nine distinct Hawkes Bay coastal areas were developed by Coastal Hazard Assessment Panels, with estimated costings over the next 100 years.

Rough costings 100 years


The panels included lay community members.   An extensive round of public meetings was held.  An “adaptive” pathway for each area had been developed.  Each path is split into three terms –  0-20 years, 20-50 years, and 50-100 years.  For each term, a preferred course of action is set out.  The range of alternatives included do nothing, more modest interventions like beach renourishment, control structures like groynes or sea walls, ‘retreating’ to more defensible coast lines, and managed retreat … the latter involving eventually moving people, homes and other assets out and relinquishing the areas to nature. Here is an example of the pathway approach with different actions for the short term, medium term and long term.

adaptive pathway example

The adaptive pathway approach involves a community deciding in advance to take action based on various “trigger points”. Examples of possible trigger points …

Possible triggers adaptive pathways J lawrence

The Bay Councils are considering an initial contribution to a ‘Coastal Response Contributory Fund’ to accumulate reserve funds.  They are hoping for central government assistance which seems likely to be forthcoming. Hawkes Bay Councils believe their collective process will help position their region strongly. This is another great reason for our councils to collaborate and start this process without delay.  TCDC signing the NZ-wide Mayoral Declaration on Climate Change would also greatly assist in gaining central government funding.

When the public gets a chance to have their say on TCDC’s Long Term Plan in a few weeks please ask Council to sign the Climate Change Declaration, to collaborate with Regional Council, and to commit the necessary funds for a coastal hazard planning project like Hawkes Bay’s.