Water movement and salinty in the Yarra and Maribyrnong estuaries

Abstract

Water movement and salinity studies have shown that the distance of salt-water penetration up the Yarra estuary is dependent upon the magnitude of the flow of the incoming Yarra River. During June, July and August 1977, salinity, temperature and current profiles showed that the Yarra and Maribyrnong estuaries had distinct stratification, the Yarra being classified as a 'salt-wedge' estuary and the Maribyrnong as a 'partially mixed' estuary. The residence time of water in the Yarra estuary was estimated to vary between 1 day and several weeks, depending upon the river flow at the time. The influence of freshwater discharge, tidal state and weather conditions are discussed.