Scientists are about to test a theory to raise Venice 30 cms by pumping water back into the soil. The idea is to pump water down 700 metres. “We have calculated that if we pump in 18 million cubic metres of clean sea water 24 hours a day for 10 years, we will raise Venice 30 cms.” Critics aren’t so sure: “This is science fiction. It is too difficult and expensive to find out what the layers of the subsoil are really like at that depth, and raising the city would not be the same as the city subsiding; it would behave quite differently and could rise unevenly, doing untold damage.”