Brisbane Water is a wave-dominated barrier estuary located in the Central Coast region, north of Sydney, New South Wales, Australia. Brisbane Water has its origin at the confluence of the Narara and Coorumbine Creeks, to the south–east of Gosford and travels for approximately 18 kilometres (11 mi) in a southerly direction to its mouth at Broken Bay, about 7 kilometres (4.3 mi) from the Tasman Sea, at Barrenjoey Head. A number of towns and suburbs surround the shores of Brisbane Water, including Blackwall, Booker Bay, Davistown, Empire Bay, Erina, Ettalong Beach, Gosford, Green Point, Hardys Bay, Kilcare, Kincumber, Koolewong, Phegans Bay, Point Frederick, Point Clare, Saratoga, Tascott, Wagstaffe, and Woy Woy. Contained within Brisbane Water is St Huberts Island, , and ; and adjoining the