Sight and Sound


Underwater sound

The sound study carried out by Styles Group will build an underwater “soundscape” for the harbour first to understand existing underwater noise levels (including crude tankers entering the harbour), then to assess noise levels from different dredging options to understand their potential impacts. This report will also inform the marine mammal study being prepared by the Cawthron Institute.

Terrestrial sound (sound of dredging operations above water)

This assessment comprises an investigation into the airborne noise levels and effects arising from the crude shipping proposal. This includes the Northport industrial site and residential properties along the Whangarei Heads coastline.


The landscape assessment carried out by Brown NZ Ltd will evaluate the proposed alterations to the harbour environment in terms of the visual, landscape, amenity and natural character effects that dredging activity will generate. These effects are assessed against existing activities within the harbour entrance and Bream Bay.

The report will also look at the temporary visual effects associated with dredging from a series of bays  – from near Darch Point and Reotahi to Urquharts Bay  – as well as the visual effects of disposal of dredge material at selected locations, on Bream Head and periodically, on part of the Bream Bay coastline.


The independent experts have been busy looking at how our proposed changes will affect noise levels in the area and what changes you might see to the surrounding landscape.

Styles Group carried out a comprehensive noise assessment using globally recognised prediction software to create their models. They concluded that noise from dredging should be comfortably compliant with relevant noise limits (including those in the Northland Regional Coastal Plan) in all affected areas. The exception is lower noise restrictions at night time which means that depending on the dredging option and vessels selected, we likely couldn’t dredge at night north of the No. 18 navigation buoy when the wind is blowing from any direction other than north.

In most cases, dredging noise is expected to fall well within the prescribed limits and be inaudible above typical sounds such as waves on the shore, birds and insects.

A visual effects impact assessment was carried out in line with relevant laws such as the Resource Management Act. This looked at the possible impact of the proposed changes – including dredging and disposal – on the landscape, natural character and amenity values of Whangarei Harbour, Whangarei Heads and Bream Bay.

The independent experts concluded that overall, there will generally be low level visual effects, and the small scale impacts of the project will not have a cumulative negative impact on the visual environment.

Adverse visual impacts are avoided because many of the proposed changes will not be visible above the water, or occur in an area that is already modified and developed e.g. in the shadow of the existing oil refinery.

If you’d like to know more of the nuts and bolts of the visual and noise effects of our proposed changes, you can read more in the related downloads section below.

If you’d like to know more of the nuts and bolts of the effects these are outlined in the summary document here.

You can read further detail in the related downloads section below.

We’ve spent a lot of time looking at the best options for dredging and disposal. Take a Deeper Dive into how this looks here.

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