Coastal Erosion

Tips for finding your property:

• Type the address in full such as 10 Example Road or 10 Example Street, instead of using street name abbreviations (Rd or St etc)
• If there are identical addresses in other parts of the District, you'll need to type in community abbreviations e.g. Beach Road (KK), Beach Road (MAK) or Beach Road (WB). Help with identical addresses
• If searching by Parcel ID, recent letters from us about natural hazards show your Parcel ID number.

How has the mapping been done?

District Plan
For Waihī Beach, Bowentown and Pukehina, the mapping shows lines predicting the extent of coastal erosion by the years 2065 (primary risk) and 2115 (secondary risk). These take into account the projected effects of climate change including sea level rise.

For the rural open coast, the erosion line is 100m back from the coast. It doesn’t specify a timeframe.

Maps outside of the District Plan
For the Tauranga Harbour, the mapping shows lines predicting the extent of coastal erosion by the years 2080 and 2130. These also take into account the projected effects of climate change including sea level rise.

To generate the coastal erosion maps we take into account the following things:

• Geology of the land
• Effects of wind, tides and waves including storm surges
• Sea level rise
• Short and long term erosion trends
• How high and stable the dunes are

Erosion mapping is not based on Annual Exceedance Probabilities (AEPs) like for other hazards. The maps are instead able to show what areas may be affected within a certain time or by a certain date. This is because erosion follows a trend (the shoreline moving inland overtime) as opposed to being an event that only happens once in a while such as flooding.

Technical Reports

Here is the report supporting the coastal erosion areas on the District Plan maps:

Here is the report supporting the other identified coastal erosion areas not shown in the District Plan:

What further work is coming up?

Council and the Regional Council are reviewing the existing coastal erosion areas along the open coastline at Waihī Beach, Bowentown and Pukehina as well as mapping new areas in other parts of the District. This includes parts of the Tauranga Harbour that haven’t been previously mapped, Matakana Island, Maketu, Little Waihi and east of Pukehina to Otamarakau.

Frequently asked questions about coastal erosion

What are the requirements if I am constructing a habitable building or shed/garage and how many am I allowed?

If your property is identified in the District Plan maps as a coastal erosion area, you will need resource consent. You will be limited to one dwelling on the property. This limitation applies even if the only dwelling is a minor dwelling (60m² or less). You are also limited to a maximum of four people for any accommodation or education facilities. This allows for the reasonable use of land for residential purposes while avoiding putting extra people at risk. You can however have more than one shed or garage because these are non-habitable buildings.

If you are constructing a habitable building, it must be relocatable e.g. on timber piles or on relocatable concrete foundations like RibRaft. You will also need a statement from someone like a relocatable housing company to show how it can be dismantled and shifted off-site. If you are building a shed or garage, you can build on standard concrete foundations. You will also need to ensure that in all cases new buildings are not going to block or be blocked by other buildings. This is because everything needs clear access to be shifted off-site if erosion occurs. These buildings will also need building consent.

If your property is identified in a coastal erosion map outside of the District Plan, Council is still required to impose controls to protect people and property from erosion based on the new information. Although we can’t require a resource consent just because of these maps, we may be able to impose controls if a resource consent is required for another reason. Otherwise, this will be done through the building consent process.

What about minor structures?

If your property is identified in the District Plan maps as a coastal erosion area, you will need resource consent for anything else that is defined as a structure in the District Plan e.g. carports and some decks, pools and tanks. The requirements will depend on what the structure is. These may also require building consent.

If your property is identified in a coastal erosion area map outside of the District Plan, Council is still required to impose controls to protect people and property from coastal erosion based on the new information. Although we can’t require a resource consent just because of these maps, we may be able to impose controls if a resource consent is required for another reason. Otherwise, this can be done through the building consent process, if such a consent is required.

What if I want to do earthworks?

This is allowed by Council; however you will also need to check with the Regional Council as it also has rules for earthworks.

Is new subdivision allowed?

If your property is identified in the District Plan maps are a coastal erosion area, subdivision isn't allowed for those properties that are fully covered by a coastal erosion area (a resource consent can’t even be applied for). However, for properties partially covered, subdivision may be allowed (subject to a resource consent) if additional titles are created outside of the coastal erosion area.

If your property is identified in a coastal erosion area map outside of the District Plan, Council is still required to impose controls to protect people and property from coastal erosion based on the new information. Although we can’t require a resource consent just because of these maps, all subdivisions require a resource consent anyway and we can impose controls or decline a consent if necessary.

There is a 6m wide "access yard" shown at the back of my property. What is this?

These access yards are shown in the District Plan on many of the properties immediately inland of Shaw Road, The Loop and Broadway Road. The access yards set aside land to allow for alterative roading access in the future if erosion removes whichever of these roads you are currently relying on. The rules allow us to say no to any buildings that might be proposed within these access yards.

Where can I find the District Plan rules for coastal erosion areas?

Within Section 8 - Natural Hazards.

Does the erosion line mapping take into account the presence of erosion control measures?

No, erosion control measures such as rock walls or dune planting are purposely overlooked because there is no certainty that they will be maintained and remain effective over the long time period considered (i.e. 50 or 100 years). However, these measures may be incorporated into future assessments if proven successful.

Why does Council have information about coastal erosion sitting outside of the District Plan?

Council is in the process of mapping coastal erosion across the District to meet new requirements. Normally, we would change the District Plan soon after identifying a natural hazard. However, there are now further steps we must take before doing a Plan Change (including risk assessment) as required by the Regional Policy Statement (RPS).

What is Council doing about coastal erosion?

Council's current approach to managing erosion includes rock revetment, stream training, dune planting through the 'Coast Care Bay of Plenty' programme and dune re-nourishment through targeted rates.

Council's future approach is detailed in the newly adopted Coastal Erosion Responses Policy.

Got a different question?

If you have any other questions, please contact Council on 0800 926 732 or at customerservice@westernbay.govt.nz.