Under Pressure Trophy

Story related and cannot be missed.

You will activate your first Water Tower as part of the main story. You'll have to climb up to the top and activate it, then choose to assign the zone to a faction (Peacekeepers or Survivors). Both will offer different rewards so choose whichever you like the most but keep in mind that you will then need to stick to the main faction for all the other zones if you don't want to miss Boot Licker .