A fun concept - I'm a fan of city-builder type games, so I quite enjoyed the playthrough. My main criticism would be that the moment-to-moment actions were a little slow, something extra for the player to manage I think would have been a good touch to give something else for the player to do (perhaps water resource management, between the remaining cities and the fire fighting ships?)
Other than that, I found that the buildings burned a bit quicker than I could react and get a firefighting ship over to them, but it was easy enough to rebuild so many times, I simply ignored the lower priority buildings to keep the ship yards up.
But overall, it was a fun game to play, and the light story element behind it was good too! Great job!