Definitions - marine sanitation device required - limitations - civil penalty.
Mo. Rev. Stat. § 306.300
in effect306.300. Definitions — marine sanitation device required — limitations — civil penalty. — 1. As used in this section, the following terms shall mean:
(1) "Marine sanitation device" , any equipment on board a vessel which is designed to receive, retain, treat or discharge sewage, and any process to treat sewage on board. Marine sanitation device includes:
(a) Type I marine sanitation device, which produces an effluent having a fecal coliform bacteria count of not greater than one thousand per one hundred milliliters and no visible floating solids;
(b) Type II marine sanitation device, which produces an effluent having a fecal coliform bacteria count not greater than two hundred per one hundred milliliters and suspended solids not greater than one hundred fifty milligrams per liter; and
(c) Type III marine sanitation device, which is certified to a no-discharge standard, including recirculating and incinerating marine sanitation devices and holding tanks;
(2) "Sewage" , human body wastes, and the wastes from toilets and other receptacles intended to retain body waste;
(3) "Vessel" , every description of watercraft, other than a seaplane on the water, used or capable of being used as a means of transportation on water;
(4) "Y valve" , a device capable of diverting the flow of marine sewage so that a vessel's marine sanitation device is bypassed and raw sewage is discharged directly into the water.
2. The following vessels equipped with an installed toilet shall be equipped with an operable marine sanitation device:
(1) A vessel sixty-five feet in length and under shall have a type I, II or III marine sanitation device; or
(2) A vessel over sixty-five feet in length shall have a type II or III marine sanitation device.
3. (1) A type I or II marine sanitation device shall have a certification label affixed that at a minimum shows:
(a) The name of the manufacturer;
(b) The name and model number of the device;
(c) The month and year of manufacture;
(d) The marine sanitation device type;
(e) A certification number; and
(f) A certification statement;
(2) A type III marine sanitation device is automatically certified and requires no label, provided it stores sewage and flushwater only at ambient air temperature and pressure.
4. While a vessel with an installed toilet is on Missouri waters, the operator shall ensure that:
(1) All pathways for overboard discharge of vessel sewage from any vessel with a type III marine sanitation device are blocked or secured in such a way as to prevent any accidental or intentional vessel sewage discharge, by disconnecting or physically blocking the onboard sewage lines or hull fittings which would allow for overboard vessel sewage discharge; and
(2) Any installed in-line Y valve shall be secured to prevent the overboard discharge of sewage from any vessel utilizing a type III marine sanitation device, by bypassing, locking, securing or disabling the valve using a padlock or nonreusable wire tie wrap, or by removal of the valve handle, or by any other method in accordance with federal regulations and standards or as approved or required by the water patrol division.
5. The chosen compliance method pursuant to subdivision (2) of subsection 4 of this section shall totally eliminate the possibility of overboard vessel sewage discharge while in waters of the state. The method chosen shall present a physical barrier to the use of the Y valve, whether accidental or intentional, so that use of the valve cannot occur without the knowledge of the operator of the vessel.
6. For any vessel offered as a noncaptained charter, the leasing entity shall:
(1) Ensure that the vessel complies with this section when presented to the lessor; and
(2) Include the lease agreement, signed by the leasing party, a paragraph outlining the operator's responsibilities pursuant to this section.
7. The provisions of this section shall not apply to any vessel operated upon the Mississippi River or the Missouri River.
8. A person who violates the provisions of this section is subject to a civil penalty not to exceed two thousand dollars.
(L. 1998 H.B. 1161 § 1) Effective 6-09-98
Source: Open US Law by Vaquill AI (CC BY 4.0)URL: https://revisor.mo.gov/main/OneSection.aspx?section=306.300Fetched: 10/17/2026