Stormwater flooding hazard information

Why NPDC is publishing this data

NPDC is sharing information about flooding risk to:

• Help the community understand natural hazards and prepare for potential emergencies caused by extreme weather.
• Establish the limitations to development and construction of buildings on areas that are affected by flooding hazards, affecting District Plan conditions.

The Resource Management Act 1991 makes NPDC responsible for controlling any effects of the use, development or protection of land to avoid or mitigate natural hazards. Our stormwater discharge consent also requires us to avoid or minimise adverse flooding of land and property. Mapping flood hazards helps us fulfil these requirements.

NPDC’s FLOOD VIEWER is an interactive tool to share the data about flooding hazard that council has available. The tool is a map where you can look at the flooding risk district wide and search for a specific address to view details.

What does it mean to me?

It enables you to prepare an emergency plan for an extreme weather event. The flood information can also inform what you can do on your property, particularly if you’re intending to develop.

People must avoid making flooding worse on any other properties by blocking or diverting flood water. For example, by changing the shape of the ground at your backyard (like building a raised garden) or building fences, you could inadvertently direct water on an overland flow path towards your neighbours, or even towards your own house.

Flood maps can show flooding on top of your house (modelling considers the ground elevation without buildings); whether your house will flood or not depends on the height of the floor in relation to the flooding level around it. NPDC doesn’t have floor elevation data of existing houses but we can provide details about the flooding at your property, including predicted flood levels in a one per cent AEP rainfall event, for areas where we already have updated flood models.

What a land information memorandum (LIM) will say about flooding on a property

Where the property lies within a flood hazard area identified in the District Plan, its LIM will simply state that a flood hazard is present for the one per cent AEP rainfall event.

You can use the stormwater flooding hazard viewer to understand flood risk at specific locations.

Will flooding affect property value and insurance cost?

NPDC cannot advise on how flood information affects insurance cover. If you have questions, we recommend discussing this with an insurance provider. Insurance policies often require policy holders to advise the insurer of any new information about natural hazards on an insured property.

Council will not review valuation of properties due to flooding risk. The public, including insurance companies, can access the stormwater flooding hazard viewer.

Thinking about development?

If your property is affected by a flooding hazard or has an overland flow path, special rules may apply to ensure that the development is safe. We recommend that you get a flood risk assessment report if you are planning to develop property that is in or close to an area affected by a flood hazard.