Pittwater is a semi-mature tide dominated drowned valley estuary, located about 40 kilometres (25 mi) north of the Sydney central business district, New South Wales, Australia; being one of the bodies of water that separate greater Metropolitan Sydney from the Central Coast. The total area of the Pittwater is 18.4 square kilometres (7.1 sq mi) and around ninety percent of the area is generally administered by the Hawkesbury–Nepean Catchment Management Authority, in conjunction with Northern Beaches Council.