Czech Republic - Overlap between surface water and groundwater

1 (billion cubic meters per year) in 2020

Between 2001 and 2020, Czech Republic overlap between surface and groundwater remained stable at around 1 billion cubic meters per year.

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What is overlap between surface and groundwater?

Part of the renewable freshwater resources that is common to both surface water and groundwater. It is equal to groundwater drainage into rivers (typically, base flow of rivers) minus seepage from rivers into aquifers

What is Czech Republic overlap between surface and groundwater?