Effects of climate change on soil movement

Subsidence is the sinking of the land due to the movement of underground materials, either from human activities or natural events. Climate change is shifting seasonal patterns, levels of precipitation and temperatures, which consequently affects soil’s water content. The amount of moisture within the soil directly impacts soil movement.

Weather Extremes

Sudden and frequent changes in groundwater levels destabilise the swelling and contraction of the foundational soil.

Water Erosion

With increased frequency and quantities of rain in some areas, water flows and pools in the soil can result in the washing away and softening of foundational soil.

Extreme Drought

In extreme drought, humans and vegetation extract water from the groundwater, as the pressure changes the soil becomes unstable, causing fissures, cracks and sinkholes.

Soil movement and climate events pose substantial economic risks to homeowners and property investors.

Learn more about how climate change is expected to impact Australian property.

Contextual Data

Soil type, precipitation records and surrounding vegetation all impact the risk of soil subsidence. The Climate Risk Engines analyse the risk of soil subsidence due to drought using information on annual precipitation records, soil types and surrounding vegetation.

Soil Moisture

Extreme drought may contribute to the shrinking of foundational soil, while extreme rainfall events may cause swelling.

Soil Type

Expansive soils such as reactive clay are sensitive to fluctuations in moisture levels and can cause sinking while sandy soils can dry out and cause destabilisation.

Surrounding Vegetation

Vegetation with high water consumption can exacerbate the “shrink-swell” effect while complex root systems may cause instability to building foundations.

Soil Movement, Soil Movement, Climate Valuation
Soil Movement, Soil Movement, Climate Valuation

Asset Data

The type of foundation used for a property is key in determining its susceptibility to damage due to soil subsidence. While the materials used for foundations are important, the physical design of the foundation is the distinguishing factor.

The deeper the foundational pillars can reach, the more stability they can offer the property. Deeper foundations generally reach depths of more than 3 metres, can bear more weight and are better suited to weaker ground. Buildings on light strip footings or unstiffened slabs are vulnerable to soil movement as they have a lower weight-bearing capacity and can be at risk of movement.