Excerpt from Marine Safety Manual
Volume II, Chapter 18
Marine Sanitation Devices (MSDs)
1. Introduction. Section 312 of the Federal Water Pollution Control Act (FWPCA), as amended (33 U.S.C. 1322), required MSDs to prevent the discharge of untreated or inadequately treated sewage into U.S. waters. It requires a certified operable marine sanitation device (MSD) on every vessel with an installed toilet. Installed toilets that are not equipped with an MSD, and that discharge raw sewage directly over the side, are illegal. Section 312(g)(2) of the FWPCA directs the Coast Guard to certify MSDs and 33 CFR 159 sets out equipment construction and operation requirements. In addition, the MSD must be in operable condition to the satisfaction of the USCG boarding officer. A vessel with no installed toilet is not subject to the provisions of section 312. Marine Sanitation Devices are “certified,” not “approved” for two reasons. First, MSDs are required on all vessels, not only USCG inspected vessels. Seconds, MSDs are tested for compliance with the Environmental Protection Agency (EPA) effluent regulations and standards as required by the FWPCA, and do not always meet the USCG marine and electrical engineering regulations of 46 CFR Subchapters F and I. MSD certifications will note whether the MSD is certified for inspected vessels or uninspected vessels.
2. Classification. The USCG recognizes three MSD equipment classes. It is vital to recognize that an MSD type is based on the equipment installation. For example, a malfunctioning flow-through discharge device that has a closed overboard discharge valve is NOT a no-discharge device. It is a broken machine.
a. Type I. A flow-through discharge device that, under the test conditions described in 33 CFR 159.121, produces effluent having a fecal coliform bacteria count no greater than 1000/100 milliliters, and no visible floating solids. A Type I MSD is commonly a physical / chemical type (macerator / chlorinator).
b. Type II. A flow-through discharge device the, under the test conditions described in 33 CFR 159.121, produces effluent having a fecal coliform bacteria count no greater than 200/100 milliliters, and suspended solids no greater than 150 milligrams/liter. A Type II MSD is commonly a biological (aerobic digestion) plant, but several physical / chemical plants are certified as Type II MSDs.
c. Type III. A device designed to prevent the overboard discharge of treated or untreated sewage, or any waste derived from sewage. Most Type IIIs are holding tanks, but there are also vacuum collection systems, incineration systems, recirculation systems, and a composting system.
3. Applicability. Vessels with installed toilets must install an operable, certified MSD, as follows:
a. Vessels 65 feet in length and under must have a Type I, II, or III device (Type I MSDs are still permitted on new installations because of a USCG waiver issued by Federal Register notice of Monday, 10 July 1978); and
b. Vessels over 65 feet in length must have a Type II or III device. Type I devices are permitted only if:
(1) The construction of the vessel was begun before 30 January 1975 and the MSD was installed prior to 31 January 1980; or
(2) The construction of the vessel was begun before 30 January 1975 and the MSD was installed before 31 January 1979 (extended from 1978 to 1979 because of a USCG waiver issued by Federal Register notice of Monday, 28 November 1977).
Failure to comply with this Federal Regulation is punishable by a fine of up to $2,200.