Once you get your water issue resolved you'll need to get your filter changed out.
I suggest you do this: Park truck and let it sit for awhile so things settle in the tank and water settles out. Put a 2-liter bottle over the end of your drain hose then open the drain valve. Hop in your rig and bump the starter (do not start engine). The transfer pump will run for 20 seconds or so and quite a bit of fuel will pump into the bottle.
Check the bottle for water, keep repeating this until the water is gone. Then I would replace your fuel filter, and be sure to inform the station where you filled up of the problem.
Vaughn