Coromandel Harbour

Coromandel Harbour is a large coastal embayment type estuary, located in the Hauraki Gulf on the west coast of the Coromandel Peninsula. The harbour has a total area of 25.4 km², is shallow and dominated by large intertidal sand and mudflats making up approximately 21% of its area. It has a relatively small catchment area of 60 km².

The harbour has high recreational use and is used for commercial and recreational harvesting of seafood. Many oyster farms are located within the harbour (intertidal areas) and mussel farms near the harbour entrance.

In the past Coromandel Harbour received a high amount of sediment and nutrients from mining and land clearance in the catchment. The harbour is currently under increasing pressure from human activities within the harbour (marinas, jetties, marine farming), around the harbour margin (urbanisation) and further into the surrounding catchment (forestry, land modification/farming).

Coromandel Harbour is sheltered from the sea by peninsulas to the north and south, and islands to the west. The harbour has important ecological communities including marine invertebrates, shellfish beds and a range of inshore fish species (including snapper, flounder, kahawai and trevally). Coromandel Harbour also provides habitat for rare and threatened wading and coastal bird species (including New Zealand dotterel, banded dotterel, bar-tailed godwit).

The harbour is a significant site to Hauraki Iwi.

Estuary summary

What makes my estuary unique?

Explore the characteristics of this estuary

Overview

Estuary characteristics

Significant features
- extensive seagrass beds
- large mangrove stands
- largest island is Whanganui Island

Total area
2540 hectares

Total shoreline length
37 km

Tide
Tide range (m) (spring/mean/neap) - 2.77 / 2.38 / 1.98

Key rivers
- Waiau River

Highlighted reports

These links are from your regional councils and unitary authorities and provide additional information about this estuary

Regional Estuary Monitoring Programme (REMP)

Related factsheets

For more details on particular topics see these factsheets

Understanding estuaries Estuary types

Department of Conservation

Want to connect with restoration groups or explore your local estuary? You can find more information on the DOC’s interactive maps.

Restoring estuaries map Experiencing estuaries map

What's happening upstream?

See results from monitored river quality sites influencing this estuary

River quality

What's happening upstream?

The physical characteristics and health of estuaries are influenced by the rivers and streams flowing into them. For instance, when it rains the mud and contaminants generated on land can be washed into rivers and eventually flow into the estuary. The health of our rivers and streams can therefore be very important for Estuary Health, and understanding the upstream pressures can help with interpreting estuary monitoring data.

Monitoring is undertaken for a range of river health indicators (e.g., water quality and ecology) in many catchments across the region. Where there are monitored river catchments that influence this estuary, these are shown below. You can click through to view monitoring results from these River Quality sites to see current state and how health has changed over time.

Waiau River

1 site

What surrounds my estuary?

See land cover information from monitored catchments that surround this estuary

Land cover

What surrounds my estuary?

The physical characteristics and health of estuaries are influenced by local geography and the way we use our land. This is because estuaries are the receiving environments for many of our land use activities. Land cover information can be used as an indicator of land use, therefore knowing the surrounding land cover can help us understand which pressures might be affecting Estuary Health.

Where there is land cover information available for nearby catchments, these are listed below. These figures show the types of vegetation and built or natural features that surround the estuary margins and the rivers that flow into this estuary. You can click through to the Land Cover topic to see these land cover classes broken down into further detail, and view changes over time.

Waiau River

What do the Broad Land Cover Classes mean?

Land cover information on LAWA is grouped into land cover classes at two levels of detail – broad and medium. For this overview we are showing the six broad-level classes for the catchment.

Forest

Inclusive of; indigenous and exotic forest.
Scrub / shrubland

Inclusive of; indigenous and exotic scrub / shrubland.
Grassland / other herbaceous vegetation

Inclusive of; tussock and exotic grassland and other herbaceous vegetation.
Cropland

Inclusive of; cropping / horticulture.
Urban / bare / lightly-vegetated surfaces

Inclusive of; natural bare/lightly-vegetated and artificial bare surfaces, and urban area
Water bodies