The Tweed River mouth on the Gold Coast of Queensland, Australia, has undergone extensive modification. Initial operations involved the construction of rock training walls to stabilise the river mouth and to maintain a deep navigation channel. These modifications interrupted the natural longshore transport and ebb tidal delta processes causing accretion on Letitia Spit and contributing to the erosion of southern Gold Coast beaches. In 2001 a sand bypassing system was built to mimic the natural longshore transport, pumping sand from Letitia Spit to southern Gold Coast beaches. Initial operations brought public concern over wide beach widths, however, the sand bypassing system has been highly successful in maintaining a deep navigation channel in the Tweed River entrance and delivering sand to southern Gold Coast beaches.