Impacts of Climate Change: Infrastructure in South West WA Bill Grace

Climate Change in South Western Australia PerthNow Annual average max. temperature (ºC) Dec-Feb days above 35ºC Annual rainfall (mm) Annual moisture balance (mm)

The Impacts on Infrastructure Direct Damage Rising sea levels Storm damage Flooding Indirect Effects Power Water

Sea Level Rise “ It is highly likely that coastal erosion due to long-term sea level rise associated with global warming will have a significant impact on Australia’s coastal systems, and any associated infrastructure, over the next century.” Natural Hazard Risk in Perth, Western Australia Geoscience Australia 2005

Sea Level Rise An increase in global temperatures will result in a sea level rise of 0.09 to 0.88 m between 1990 and 2100, with a central value of 0.48 m. Over the next 50 years the projected global sea level rise is 0.05 to 0.32 m, with a central value of 0.18 m IPCC, 2001

Perth Coastal Plain - Erosion The majority of the Perth coastal region is not at risk of significant erosion. At three localities (Port/South Beach, Swanbourne Beach, Pinaroo Point), however, are prone to erosion from storms and sea level rise, resulting in significant risk to urban development. Bunbury to Mandurah sector appears to be most susceptible to coastal erosion over the next century. The Hillarys to Yanchep sector does not appear to be susceptible to erosion over the next century. The Cape Naturaliste to Bunbury sector may be impacted by coastal erosion associated with long-term sea level rise.

Storm Damage Tropical cyclones Preferred paths and poleward extent may alter, but changes remain uncertain. If they were to travel further poleward they would be more likely to impact on coastal regions in south- west Western Australia, southern Queensland and northern NSW. Storms Climate models also indicate a future decrease in the number of storm centres over southern Australia but an increase in their intensity.

Power Supply Likely impacts on electricity generation from climate change: warming by 1 ºC can lead to a 3% decrease in thermal efficiency in some facilities, and a decrease in transmission line efficiency changes in demand, especially affecting peak generation capacity required for air conditioning The effect of higher temperatures is likely to be considerably greater on peak energy demand than on net demand, suggesting that there will be a need to install additional generating capacity over and above that needed to cater for underlying economic growth.

Water Supplies

Gnangara Mound Depletion

Projected Demand

Insurance There is growing concern in the insurance industry about the potential for large rises in insurance claims as a result of climate change. This could result in: higher premiums, restricted coverage or withdrawal of insurance from areas of high risk, potentially resulting in significant economic and social ramifications.

Mitigation Strategies The Institution of Engineers, Australia [2000] identified marine climate change and its effect on the coastal zone as the most important research priority for coastal and ocean engineering in Australia; All infrastructure providers with physical assets (transport, power, water, telecoms etc) need to consider climate change impacts in risk management strategies (including insurance); WAPC and Local Government in the south west need to include sea level rise in their planning schemes and coastal management strategies; Changing patterns of energy demand to be taken into account in power generation; Adaptation - building design / retrofit to reduce A/C demand Water supply planning already taking climate change into account Adaptation - water use efficiencies and climate insensitive sources Stewardship of groundwater resources