And flood basalts are more frequent than once every 200 myr as well. More like every 30-50.

It can be misleading to present the 97% of water across the Earth in the oceans as inaccessible and unusable. It is in fact a massive reservoir that supplies much of our freshwater via evaporation and precipitation working as an enormous perpetual and natural desalination system. At every moment, evaporated seawater is replenishing the water cycle somewhere on Earth.

David, in his writing about groundwater, a little misleadingly (and I assume unintentionally) gives the impression that all groundwater is in effect ‘mined’. Most aquifers across the world are exploited sustainably, though of course, some are not. There are some also truly mined as unreplenishable reservoirs. On the whole, most groundwaters in the UK are managed sustainably thanks to the rigorous work of the Environment Agency.