Warringah Council was formed in 1906, giving Dee Why residents a local government. In 1911 it was decided that the tram line that had expanded in sections from Manly since 1903 was to be extended from Brookvale on to Collaroy Beach via Pittwater Road, and soon after to Narrabeen. The line opened on 3 August 1912 with an hourly service, and it was perhaps this development that caused the Salvation Army in 1913 to progressively sell off most of its holdings on the Northern Beaches, starting with The Oaks Estate Auction, which gave its name to one of the main streets of Dee Why, Oaks Avenue. Another main street, Howard Avenue, commemorates Commissioner Thomas Howard, the first commissioner of the Salvation Army in Australia and New Zealand. By 1920, most of Dee Why had been subdivided. From the end of 1938, the trams, as a result of losses due to low population density and competition with new bus routes that duplicated their services, operated only at peak hours for commuters and on weekends for tourists, and finally ceased operating with the final run on 30 September 1939.