The Australian Department of Climate Change has released the results of a study of the effects of rising sea levels as a result of climate change on Australia’s coastal dwellings and infrastructure.

The modelling assumed a sea level increase of 1.1 metres, which it describes as the “plausible worst case”,  by 2100.

The key findings of the report were:

  • Between 157,000 and 247,600 properties were identified as potentially exposed to inundation with a sea-level rise of 1.1 metres.
  • Nearly 39,000 properties, located within 110 metres of “soft” shorelines, are at risk from accelerated erosion.
  • The current value of buildings at risk from inundation is between $41 and $63 billion.
  • Infrastructure considered to be at risk because it is located within 200 metres of a shoreline includes 269 police, fire, ambulance and emergency service facilities and 75 hospitals and health services facilities.
  • Eight electricity and water treatment facilities are regarded as being at risk.
Narrabeen/Collaroy in 2009 and with 1.1m sea level rise and a 1-in-100 year storm surge.
Narrabeen/Collaroy in 2009 and with 1.1m sea level rise and a 1-in-100 year storm surge.

On a state-by state basis, the study’s findings were:

New South Wales

  • Between 40,800 and 62,400 residential buildings are at risk of inundation with a 1.1 metre sea level combined with a 1-in-100 year storm;
  • The areas with the greatest risk are Lake Macquarie, Wyong, Gosford, Wollongong, Shoalhaven and Rockdale.
  • The areas of Sydney with greatest vulnerability are Rockdale/Botany Bay and Narrabeen/Collaroy.
  • The area of Rockdale/Botany Bay at risk includes Sydney Airport.

Victoria

  • Between 27,600 and 44,600 residential buildings are at risk of inundation with a 1.1 metre sea level combined with a 1-in-100 year storm;
  • The areas of greatest risk are Kingston, Hobson’s Bay, Greater Geelong, Wellington and Port Phillip.
  • One of the most vulnerable areas in Australia is the Gippsland Lakes/Ninety Mile Beach area.
  • The townships of Lakes Entrance an Port Fairy are particularly vulnerable.
  • In Melbourne, the St Kilda area, including the Marina and Lona Park are at risk.

Queensland

  • Between 35,900 and 56,900 residential buildings are at risk of inundation with a 1.1 metre sea level;
  • The areas of greatest risk are Moreton Bay, Mackay, the Gold Coast, Fraser Coast, Bundaberg and the Sunshine Coast;
  • The Queensland analysis did not include the effect of storm surges. A 1-in-100 year storm tide, combined with a 1.1 metre sea level rise, would effect more than 2,500 buildings in Cairns, including Calvary Hospital and the police headquarters.

South Australia

  • Between 35,900 and 56,900 residential buildings are at risk of inundation with a 1.1 metre sea level;
  • Charles Sturt and Port Adelaide/Enfield are the areas most at risk
  • Small coastal towns on the Yorke Peninsula are particularly at risk. Approximately 80% of Fisherman’s Bay is at high risk.

Western Australia and the Northern Territory

  • Between 35,900 and 56,900 residential buildings in Western Australia and 190 in the Northern Territory are at risk of inundation with a 1.1 metre sea level;
  • Busselton, Mandurah, Rockingham and Bunbury have the most properties at risk;
  • Increased tropical cyclones pose a risk in the Broome-Exmouth region.

Tasmania

  • Between 8,700 and 11,600 residential buildings are at risk of inundation with a 1.1 metre sea level combined with a 1-in-100 year storm;
  • Clarence, the Central Coast, Break O’Day and Waratah/Wynyard are most at risk;
  • Compared with the rest of Australia, a large proportion of Tasmania’s coast is rocky or sandy shores backed by bedrock and is unlikely to suffer erosion.