WIVENHOE DAM

Full text  HERE

Extract:

   …Wivenhoe has a clay core and an earthen wall which is lined on the outside with rocks. Unlike Somerset Dam which has a concrete wall, Wivenhoe has no structure which could withstand the force of water flowing over its wall. If over-topped by flood-water, the Wivenhoe wall would quickly erode and fail, releasing the contents of a full Wivenhoe to flow down the Brisbane River at torrential speed…