Current MARPOL legislation stipulates that separated bilge water containing 15 ppm or below in water can be disposed into international waters. Some national, regional and local authorities have more stringent regulations. In the United States and in the Baltic and North Seas disposal of separated bilge water is only permitted at least 12 nautical miles from shore. In the future, legislation is expected to become even more stringent, requiring levels of oil in water to be reduced further to five ppm for discharge at sea and to zero-discharge in sensitive waters.