Skip to main content

Story: Marine conservation

Silt plume, Cass River

Image
Silt plume, Cass River

While this discoloured water off the Cass River mouth in Lake Tekapo is in fresh water, similar plumes occur where rivers carrying high sediment loads enter the sea. While sediment entering the ocean through streams and rivers is natural, poor land use can greatly exaggerate this process – with resulting silt plumes. If too much sediment settles it can smother seaweed and creatures living on the sea floor.

Using this item

Air Safaris

by Tim Rayward

This item has been provided for private study purposes (such as school projects, family and local history research) and any published reproduction (print or electronic) may infringe copyright law. It is the responsibility of the user of any material to obtain clearance from the copyright holder.

All images & media in this story

How to cite this page

Gerard Hutching and Carl Walrond, Marine conservation – Pollution, Te Ara – the Encyclopedia of New Zealand, https://teara.govt.nz/en/photograph/5832/silt-plume-cass-river (accessed 14 June 2026).

Story by Gerard Hutching and Carl Walrond, published 2 March 2009, updated 1 September 2015.