Beginning in March 2012, the following vessels will be prohibited from discharging all sewage, whether treated or not, while in California marine waters:
- Large passenger vessels over 300 gross tons or more that have berths or overnight accommodations for passengers
- Large oceangoing vessels over 300 gross tons, including private, commercial, government, or military vessels equipped with a holding tank with remaining capacity at time of entry or containing any sewage generated prior to entry to California marine waters.
California marine waters are defined as the territorial sea measured from the baseline as determined in accordance with the Convention on the Territorial Sea and the Contiguous Zone and extending seaward a distance of three miles, and all enclosed bays and estuaries subject to tidal influences from the Oregon border (41.999325 North Latitude, 124.212110 West Longitude, decimal degrees, NAD 1983) to the Mexican border (32.471231 North Latitude, 117.137814 West Longitude, decimal degrees, NAD 1983).
Holding tanks include any tank specifically designed, constructed, and fitted for the retention of treated or untreated sewage that has been designated and approved by the ship’s flag administration on the ship’s stability plan; a designated ballast tank is not a holding tank for this purpose.
Gross tons are measured under the International Convention on Tonnage Measurement of Ships, 1969, measurement system in 46 U.S.C. § 14302, or the regulatory measurement system of 46 U.S.C. § 14502 for vessels not measured under § 14302.
This No Discharge Zone overlaps with portions of the four NOAA national marine sanctuaries, adjacent to the California coast and is consistent with the existing prohibitions on vessel sewage from large passenger and large oceangoing vessels within the sanctuaries.
for further information please refer to the below link to a US Environmental Protection Agency fact sheet for the Californian NDZ.