You may have noticed our team out and about collecting the data, and many have been approached and asked what they are doing. They are downloading shallow groundwater level data that has been collected every 15 minutes over the past nine months or so. Groundwater levels are not static, but respond to many factors, including rainfall, river flow and tides. In low-lying coastal areas, sea level rise can cause rising groundwater over longer time periods.

Shallow groundwater is “out of sight, out of mind” for many people, but presents a hazard with potential to affect people in multiple ways. Groundwater can contribute to other hazards including surface runoff, river flooding and coastal-storm inundation. 

It can also cause instability in building foundations, cause damage to roads, can infiltrate into stormwater and wastewater systems, lead to dampness and mould issues in housing, increase liquefaction potential, and can emerge above ground to cause flooding, pollution, salinity stress or other environmental issues. 

This under-appreciated hazard is gradually becoming more recognised by councils as an issue, and something that is only likely to get worse under climate change.