Assessing Climate Change Impacts on Infrastructure Using IPWEA’s Manual

The Institute of Public Works Engineering Australasia (IPWEA), the association of professionals delivering public works and engineering services in Australia and New Zealand, has released an outstanding resource for infrastructure managers wanting to understand the impacts of climate change on assets and infrastructure.

IPWEA’s Climate Change Impacts on the Useful Life of Infrastructure Practice Note 12.1 (2018) accompanies Practice 12, and infrastructure managers should use both together.

The Practice note “provides a methodology and guidance for asset managers on assessing the impact of climate change on infrastructure useful life to the year 2100 to help entities obtain a more reliable annual depreciation expense and consequently more reliable operating results.”

The note contains the following information, and each section includes a case study to illustrate the topics discussed.

• Using global climate models, we can examine present and future climate change trends in temperature increases, rainfall patterns, ocean changes, heat waves, bushfires, high wind events, and cyclones.

• Climate change impacts infrastructure such as bridges, footpaths, sealed and unsealed roads, buildings, etc., and the physical damage and usage effects caused by climate change. This section also provides a case study that applies current climate trends and future climate projections to improve an existing road and bridge prone to heavy rains and flooding in Warriewood, Sydney.

• Climate change impacts asset materials like concrete, bitumen, steel, wood, and PVC, causing physical damage and chemical deterioration. A case study of Collaroy Beach’s Stormwater outlet shows how climate adaptation is incorporated into its stormwater replacement outlet’s design. A storm event destroyed the stormwater outlet, terminating its useful life. A high-density polyethylene (HDPE) pipe is built into the seawall to increase its useful life and protect it against corrosion from storm events.

• Climate adaptation measures usually follow these three strategies: accommodate, protect/defend, and retreat. These can be applied to climate change effects like high temperatures or heat waves, low rainfall or drought, increased bushfire weather, sea-level rise, and saltwater intrusion.

• Quantitative modelling of climate change: This section identifies climate models available in Australia and New Zealand and the assets and climate variables in each model to estimate the impacts of climate change on the asset’s useful life.

• This is a guide for asset managers to estimate the impacts of climate change on an asset’s useful life through the Decision Tree Worksheet. The decision tree worksheet involves five steps: identifying the existing asset, expected climate changes and impacts, adaptation measures, estimating the change to an asset’s useful life, and actions taken.

“The Practice note is designed to raise awareness of climate change and its potential impacts to infrastructure and assets, help asset managers make informed decision to minimize and even extend the life of existing vulnerable assets, and consider the cost of a premature end to useful life caused by climate change.”

To get a copy of the Practice Note 12.1, click the link below: