I got this from wikipedia if it helps. Interesting read...
The Harbord Estate was named to honour the wife of New South Wales Governor Lord Carrington (Robert Wynn Carrington) (1885–1990). Before her marriage, Lady Carrington was the Honourable Cecilia Margaret Harbord.
For many years, the beach and the district behind it was known as Freshwater which was probably named after the stream of fresh water that ran down to the beach (now Oceanview Road). However, some time after the naming of Harbord Estate, a number of residents began to believe that the holiday image of Freshwater should be upgraded by a name change to Harbord. The change of name attracted much controversy and debate and occasionally became quite heated. When the first local district school was built in 1912, a petition was sent to the Minister of Education requesting it should be called Harbord Public School. The Minister declined and officially opened it Freshwater Public School. Pressure was then directed towards renaming the post office. The Postmaster-General finally accepted the views of those who wanted a residential image and Freshwater officially became Harbord on 1 September 1923.
Freshwater Bay Post Office opened on 20 April 1909 and was renamed Freshwater in 1912.
In 2003 the Harbord Chamber of Commerce submitted a request to Warringah Council to support an application to the Geographical Names Board of New South Wales to rename the suburb of Harbord to Freshwater. In public consultation 774 voted in favour and 161 voted against with the results recorded in council minutes on 8 March 2005. The suburb of Harbord was officially named Freshwater on 12 January 2008.
A council survey found 82 per cent of residents thought the change was a good idea. One said "the name Freshwater sounds much more appealing and will help real estate values", while another thought "the name of the suburb and the beach should be the same". "It sounds as though it's a move to gentrification." The area had "seen a level of uplift ... over the last 10 years of so".