Story: Ocean currents and tides

Low tide at Manukau Harbour

Estuaries like Manukau Harbour change with the outgoing tide from a coastal inlet to mudflats. Currents in estuaries are mainly generated by tides, and wash sediment in and out along channels visible at low tide.

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GNS Science

Reference: CN22762

by Lloyd Homer

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How to cite this page

Craig Stevens and Stephen Chiswell, Ocean currents and tides – Fiords, estuaries and river plumes, Te Ara – the Encyclopedia of New Zealand, https://teara.govt.nz/en/photograph/5937/low-tide-at-manukau-harbour (accessed 25 June 2026).

Story by Craig Stevens and Stephen Chiswell, published 2 March 2009.