Regulations on Sewage Systems

1. This Regulation comes under MARPOL Annex IV, Chapter 3 - Equipment and Control of Discharge, Regulation 9
2. Every ship is required to comply with the provisions of this Annex shall be equipped with one of the following sewage systems:

1. A sewage treatment plant which shall be of a type approved by the Administration, taking into account the standards and test methods developed by the Organization.
2. Sewage comminuting and disinfecting system shall be approved by the Administration. Such system shall be fitted with the facilities to the satisfaction of the Administration, for the temporary storage of sewage when the ship is less than 3 nautical miles from the nearest land.
3. A holding tank of the capacity to the satisfaction of the Administration for the retention of all sewage, having regard to the operation of the ship, the number of persons onboard and other relevant factors. The holding tanks shall be constructed to the satisfaction of the Administration and shall have the means to indicate visually the amount of its contents.
1. Every Passenger ship is required to comply with the provisions of this Annex shall be equipped with one of the following sewage systems:
1. A sewage treatment plant which shall be of a type approved by the Administration, taking into account the standards and test methods developed by the Organization.
2. A holding tank of the capacity to the satisfaction of the Administration for the retention of all sewage, having regard to the operation of the ship, the number of persons onboard and other relevant factors. The holding tanks shall be constructed to the satisfaction of the Administration and shall have the means to indicate visually the amount of its contents.

Reference: IMO Publications & Documents - International Conventions - MARPOL - Annex IV