Okay, i really need some guide here. How to enter the water facility? I can say it is still in the beginning of the game (after tutorial). I'm outside of the facility, i can see two giant size door but it seem i can't enter the facility.

You can bash down the front door (the one that's between the two walls which are protected by spikes on the ground). You have to hit it quite a few times to destroy it.

As DoctorGOGgles said, there are two big wooden doors in the front with a hole above them for the outlaws to shoot at you from. The doors require a lot of bashing.

I found another way, you need to shot one of the pillar at the outside of the water facility. Then it will break and make path which you can enter from above. I love this game, it has non linear approach.

Good to see you found a solution. I might have a look myself, cause i didn't find that one.