Estuarine waterways
Carrum Carrum Swamp once extended from present-day Mordialloc to Frankston, approximately 44 square kilometres, fed by small creeks with headwaters in the Dandenong Valley. The resource-rich, freshwater wetland was isolated from seawater in the bay by a broad sand ridge and outflow from the swamp to the bay was confined to two outlets – Mordialloc Creek and Kananook Creek.
Draining of Carrum Carrum Swamp to allow for farming began in 1879. Subsequent housing development on flood-prone land led to Mordialloc Creek being considered primarily as a flood control medium. Industrialisation and urbanisation caused serious pollution problems in the creek and by 1975 Mordialloc Creek was considered to be one of the most polluted waterways draining into the bay.
An outcry from Bayside conservation groups led to the Dandenong Valley Authority working to improve water quality. Melbourne Water has superseded the DVA in management of this waterway.
Wetlands offer new ways to treat urban run-off and associated pollutants. CSIRO scientists have found that aquatic plants offer a low cost alternative for removing excessive nutrients and heavy metals. Phragmites (reeds) in the creek help to stabilise banks and also remove nutrients from the water. The reed beds and sandbars provide safe habitat for water birds and other species. Conservation groups lobbied for the retention of a natural bush setting for the creek and environs. The Swamp paperbark groves opposite the Chute Street boat ramp have been preserved as a remnant of the original vegetation.
