<P> Cruise ships that are 79 feet (24 m) in length or greater, are subject to the requirements of the EPA Vessel General Permit (VGP). The most recent VGP was published in 2013 . EPA issued a separate permit for smaller cruise ships, however this permit currently only applies to ballast water . A Congressionally - imposed moratorium applied to other wastestreams for these vessels until January 19, 2018 . </P> <P> The Department of Justice prosecutes violations of federal laws . In addition, the Department of State represents the United States at meetings of the IMO and in international treaty negotiations and is responsible for pursuing foreign - flag violations . Other federal agencies have limited roles and responsibilities . For example, the National Oceanic and Atmospheric Administration (NOAA, Department of Commerce) works with the Coast Guard and EPA to report on the effects of marine debris . The Animal and Plant Health Inspection Service (APHIS) is responsible for ensuring quarantine inspection and disposal of food - contaminated garbage (these APHIS responsibilities are part of the Department of Homeland Security). In some cases, states and localities have responsibilities as well . </P> <P> Commercial vessels are required to obtain NPDES permits pursuant to Section 402 of the Clean Water Act . Section 312 of the Act prohibits the dumping of untreated or inadequately treated sewage from vessels into the navigable waters of the United States (defined in the act as within 3 miles (4.8 km) of shore). Cruise ships are subject to this prohibition . Commercial and recreational vessels with installed toilets are required to have marine sanitation devices, which are designed to prevent the discharge of untreated sewage . Beyond 3 miles (4.8 km), raw sewage can be discharged . On some cruise ships, especially many of those that travel in Alaskan waters, sewage is treated using Advanced Wastewater Treatment (AWT) systems that generally provide improved screening, treatment, disinfection, and sludge processing as compared with traditional MSDs . AWTs are believed to be very effective in removing pathogens, oxygen - demanding substances, suspended solids, oil and grease, and particulate metals from sewage, but only moderately effective in removing dissolved metals and nutrients (ammonia, nitrogen and phosphorus). </P> <P> States may also establish no - discharge zones (NDZs) for vessel sewage, under section 312 . A state may completely prohibit the discharge of both treated and untreated sewage from all vessels with installed toilets into some or all waters over which it has jurisdiction (up to 3 miles (4.8 km) from land). As of 2017, this designation has been used for 72 areas representing part or all of the waters of 26 states, including a number of inland states . </P>

Where does the poop go on cruise ships