Mosman is surrounded by water. Over 90 per cent of its boundary, or just over 18 kilometres, is formed by the shores of Sydney Harbour. Of this, three kilometres of sea walls provide protection and definition to many foreshore areas. At the commencement of the CEC, many of these walls were up to a century old and in a poor condition after years of exposure to salt water and wave action. While it could have been argued that maintenance and repair of seawalls is a State Government responsibility, Mosman Council chose to take the initiative.
A program of works to repair these valuable and essential community assets was established and funded via Council’s environmental levy and the CEC. Initially the sea wall repairs were proposed for the latter stages of the CEC works in 2005-2007.
However, a number of smaller projects have since been completed and three major projects brought forward as a result of successful grant applications to undertake the works. These three projects are located at Ellery Park (the Spit West), Quakers Hat Bay and Mosman Bay.
The total cost of these works is in excess of $900,000 with a total of $443,000 in funding being provided by the State Government under its Estuary Management and Coastal Management Programs. The fact that Council had in place a program of repairs and was in a position to contribute to funding of the works contributed significantly to the success of the applications for funding assistance. It also is recognition of Council’s proactive approach to these issues given that such funding was able to be secured from the State Government.
Ellery Park
The Ellery Park project was completed in 2003 and involved repairs to the sea wall at the abutment to the old Spit Bridge, adjacent to the current Spit Bridge. Council also took the opportunity to carry out major improvements to the area adjacent to the sea wall and create a new recreational area that is now known as Ellery Park. The area was previously somewhat unattractive, with bare sand and asphalt, disorganised parking and poor access arrangements. It now features a viewing deck, interpretive features to recognise the old timber Spit Bridge and tram turning area, and landscaping. The park has been named after Peter Ellery who operated a ferry across this part of Middle Harbour prior to construction of the first Spit Bridge. Ellery Park work was completed in May 2003.
Mosman Bay Seawall
The Mosman Bay seawall is a dry laid sandstone block wall that was constructed to reclaim an area of land that was previously mud flats. Typical of many sea walls found in Sydney Harbour, it is deteriorating from the washing out of fine material from behind the wall due to wave and water penetration. The project will repair the seawall by digging out the soil and fill from behind it and installing a barrier to prevent the fine material from washing out. It will still allow the drainage of water through the wall to ensure its ongoing structural stability.
Quakers Hat Seawall
The Quakers Hat Bay seawall is also an old dry laid sandstone wall. It is in much worse condition than the wall at Mosman Bay with sections having actually collapsed into the Harbour. The old wall was constructed with a vertical face. While this is quite effective at dissipating wave energy, it does not provide suitable habitat for intertidal creatures. The wall is to be repaired and strengthened by adding a new angled layer of rock, or ‘boulder field’ against the existing vertical faced wall. This will provide improved habitat for many aquatic organisms.
Council has entered into a partnership with the University of Sydney to study the effects of the altered wall profile on habitat for aquatic organisms. There is little doubt this partnership was crucial in securing State Government funding for this project.
Both the Mosman Bay and Quakers Hat Bay seawall projects are expected to be completed by September 2003.
