NO NO NO NO NO NO NO!
Potable water is potable water, and intended for human consumption, including cooking. The FDA strictly defines it. It goes in the holding tanks of Amtrak passenger cars.
Nonpotable water is not handled as carefully, and may not be guaranteed safe for human consumption. It is generally used in locomotive radiators, etc. Putting it in the potable water tanks is strictly forbidden.
If you EVER see nonpotable water being put into the potable water holding tanks of any Amtrak passenger car, report it immediately to the Conductor. Actually, it should be reported to the FDA as a Public Health violation. I suggest you report it, but don't have the appropriate contact number at hand. Maybe somebody else can provide it.
Employees who have not been trained in the proper handling of this equipment are strictly forbidden from using it. The training includes proper handling of the spigot and nozzle, clearing old water from the pipes/hose, sanitizing the nozzle and the receptacle, and proper return and securing of the hose. All OBS employees on my train received this training because refilling at Florence, SC was often necessary. At other locations, this function may be performed by employees at that location, and maybe by Conductors or AC's.
I HOPE THIS REPRESENTS A MISUNDERSTANDING. I hope the OP misidentified the potable water hose as a nonpotable hose. If the OP is correct, there is no excuse and this should be reported! It's not funny. It's not to be taken lightly.
By the way, generalized unsubstaniated rants about dragging hoses through the dirt, pigeon poop, etc., are not productive.
Tom
P.S. Can you give a better description of the person who did this? "Some guy" isn't enough of a description.
P.P.S. Edited for terminology & clarification 7/21.