Code of Federal Regulations Title 43. Public Lands:  Interior § 43.8365.2–1 Sanitation

(a) Clean fish, game, other food, clothing or household articles at any outdoor hydrant, pump, faucet or fountain, or restroom water faucet;

(b) Deposit human waste except in toilet or sewage facilities provided for that purpose;  or

(c) Bring an animal into such an area unless the animal is on a leash not longer than 6 feet and secured to a fixed object or under control of a person, or is otherwise physically restricted at all times.