Coastal hazards and the Proposed Christchurch Replacement District Plan.

The Christchurch City Plan and the Banks Peninsula District Plan are being reviewed. The end result will be the Christchurch District Plan - covering both the city and Banks Peninsula.

Coastal hazards (coastal erosion and coastal inundation management area provisions) were included in stage three proposals for the Proposed Christchurch Replacement District Plan(external link), notified on 25 July 2015.

Submissions on these coastal hazard provisions closed on Friday 16 October 2015 and a Government Order
in Council(external link)
(effective 16 October 2015) directed the removal of these provisions from the district plan review process.  Submissions received on coastal hazard provisions will not be published or passed on to the Independent Hearings Panel for consideration. There will be no opportunity for further submissions on the coastal hazard submissions.

Implications of this decision - Coastal Hazards risk

The risk from coastal hazards remains. The change is in the planning response to these hazards through Resource Management Act processes, given that central government is looking at a National Policy Statement for natural hazards and is updating its guidance on adaptation to climate change.

The Council welcomes more time to work with the community on how we respond to coastal hazards. We know how difficult this is for coastal communities.

The information in the Coastal Hazards Assessment Report (Tonkin & Taylor 2015) has not changed. The report defines coastal erosion and coastal inundation zones over a 50-year and 100-year timeframe. The Council is required to make these assessments under The New Zealand Coastal Policy Statement, which requires local authorities to identify areas potentially affected by coastal hazards over at least 100 years.

Although the report was the basis for the notification of the proposed changes to the District Plan, removing the coastal hazard provisions from the District Plan process does not change the information in the report.

The information in the report will still inform Council processes and our statutory obligations, including LIM notations and issuing building consents.

See more information on LIMs and building consents in coastal hazard areas.

While we are looking at the risk 50 to 100 years out, we are not talking about hazards that emerge after 50 or 100 years. We are talking about what is expected to happen during those 50 and 100 years - coastal inundation due to storm events and the extent of shoreline retreat due to coastal erosion.

These risks are with us today. A major storm event tomorrow would see areas of Christchurch impacted by coastal inundation and could result in coastal erosion. This risk has been exacerbated due to widespread subsidence of land, as the result of the earthquakes, and is predicted to increase with ongoing climate change and sea level rise.

For coastal inundation, we are talking about random events - storms that could come along next week, or not occur for several years. We have assessed the risk of a storm event that has the probability has a 2% chance of occurring in any one year, or once every 50 years, or 1% chance of happening each year, or once every 100 years, with sea level-rise built in to the modelling.

These are probability based - we could have two 1/50 year flood events in one year.