The Balcombe Creek is the last unspoilt and most significant waterway entering the eastern side of Port Phillip Bay. It rises south of Frankston, flows through the Moorooduc Plains and is joined by the Devilbend Creek to flow into The Briars wetland, draining an area of about 87 sq. km.

West of the Nepean Highway, the creek flows for nearly three km through riverbank bush and widens into a tidal estuary before entering the bay at Mt. Martha beach. The natural opening and closing of the mouth allows salt water to enter the estuary ... (more)