Creatine is good, no doubt about it. However, using creatine when lack of water might be a possibilty is extremely bad. Creatine causes muscles to draw water from the rest of your body. You have to make sure to drink extra water when taking creatine because of this. Also, if you are taking creatine and sweating alot from hiking you really increase the risk of becoming dehydrated. For this alone I avoid taking creatine when I am not sure how available water might be.
Most people that gain weight from creatine is not because they are getting bigger, but because the muscles are holding more water.