They are practically extinct, for obvious reasons.

https://www.google.com/search?q=chat...ih=625&dpr=1.5

A "Water castles" or Chateau d'eaux in France are still a prominent feature of many towns as many have been painted fancifully (even if unused)- indeed there is a yearly contest as to the best paintings gracing them The link I gave above shows many really neatly decorated chateau d'eaux.

Yes St Cirq is right that many water towers are being made redundant by modern pumping techniques but for the moment plenty around as the images link shows.