A Chalk Aquifer Alliance talk by Andrew McKenzie
Water levels in the Chalk naturally vary seasonally, and when levels rise high enough water will start to flow in ‘bournes’ and ephemeral streams that are often a characteristic of the Chalk landscape. In particularly wet conditions high groundwater levels can cause more widespread flooding and may cause damage or disruption to local communities. Significant groundwater flooding events occurred in 2000/2001 and 2013/2014 and triggered widespread interest from researchers, stakeholders and the affected communities. But why is the Chalk prone to groundwater flooding, and do the events of the last decades represent something new, or are we just describing something, that has always happened, in a new way?
Variability in climate and rainfall in past decades may have given us a false impression of how rare or common groundwater flooding is, and long intervals between flood events mean that the purpose of landscape and infrastructure adaptations can be easily forgotten.