MARPOL ANNEX IV - SEWAGE

Table of Content

1. Introduction

1.1 General

MARPOL Annex IV came into force on the 27th of September 2003 and contains regulations regarding the discharge of sewage into the sea from ships, ships' equipment, and systems for the control of sewage discharge, the provision of port reception facilities for sewage and requirements for survey and certification.

1.2 Goals and purpose

This document is intended to provide guidance on conducting Port State control inspections for compliance with MARPOL Annex IV and provide consistency regarding inspections, deficiency identification and the application of control procedures.

1.3 Application

The provisions of MARPOL Annex IV shall apply to the following ships engaged in international voyages:

  1. The IGF Code applies to ships using low-flashpoint fuels for which the building contract is placed on or after 1 January 2017;
  2. in the absence of a building contract, the keels of which are laid, or which are at a similar stage of construction on or after 1 July 2017; or
  3. the delivery of which is on or after 1 January 2021.

Ships of any age undertaking to use low flashpoint fuel since 1 January 2017 which is different from those it was originally approved to use before 1 January 2017, shall be treated as a ship using low-flashpoint fuels on the date which this undertaking commenced.

It does not apply to Gas Carriers, as defined in regulation VII/11.2:

  1. ships of 400 gross tonnage and above; and
  2. ships of less than 400 gross tonnage which are certified to carry more than 15 persons.

The administration shall ensure that existing ships, the keels of which are laid, or which are of a similar stage of construction before 2 October 1983, shall be equipped, as far as practicable, to discharge sewage in accordance with the requirements of regulation 11 of the annex.

1.4 Definitions and abbreviations

The PSCC Instruction containing “Definitions and Abbreviations” serves as general document and is to be used in conjunction with this Paris MoU document.

1.5 Additional Considerations

The following should be considered while applying MARPOL Annex IV:

  1. When the sewage is mixed with wastes or wastewater covered by other Annexes of MARPOL, the requirements of those Annexes shall be complied with in addition to the requirements of MARPOL Annex IV when ships are observed to be operating, or previously operated, in polar waters, special requirements of MARPOL Annex IV in accordance with Part II- A4 of the Polar Code shall be examined; and
  2. PSCOs shall be aware that there are special requirements for the discharge of sewage from passenger ships within a special area in accordance with Regulation 11.3 of MARPOL Annex IV.
  3. As per Resolution MEPC.275(69), these discharge requirements are applicable in the Baltic Sea Area. For existing [1] passenger ships which are enroute between a port located outside the Baltic Sea special area and a port located east of longitude 28°10’ E within the Baltic Sea special area and do not make any other port calls within the special area, the requirement will take effect on 1 June 2023.

2. INSPECTION OF SHIP

2.1 Pre-boarding preparation

Before boarding the PSCO should make sure that there are neither visible floating solids nor indication of cause of discoloration of the surrounding water from effluent discharged from the ship.

2.2 Initial Inspection

2.2.1 Certificates and Documents

During an initial inspection, including a tour of the ship, the PSCO should ensure that the ship has the following certificates and documents:

2.2.2 Standard Discharge Connections

The standard discharge connections for the discharge of sewage to reception facilities must meet the requirements of Reg. 10 of Annex IV.

For ships in dedicated trades, such as passenger ships on regular routes, the ship's discharge pipelines may be fitted with a discharge connection which is accepted by the Administration, such as quick connection couplings.

2.3 Clear grounds

The following non exhaustive list may be considered as clear grounds for a more detailed inspection:

2.4 More Detailed Inspection

If the PSCO has clear grounds for carrying out a more detailed inspection, the Master should be immediately informed. While conducting a more detailed inspection, the PSCO should be guided by the following:

  1. Piping and holding system for the sewage system:
    • pipelines shall be so arranged that all sewage generated from the ship is treated by the sewage systems or collected in the sewage holding tank;
    • all the sewage holding tanks in use shall be indicated on the ISPP certificate and shall have means to indicate visually the amount of its contents; and
    • while the vessel is in port and/or in specific areas, the overboard valves for direct discharge of untreated sewage shall be kept closed.
  2. Visual inspection of the sewage treatment plant (if fitted) including type, nameplate, structural integrity and signs of leakage.
  3. Working condition of the sewage treatment plants aeration system, where applicable. In cases where an aeration system does not deliver a continuous source of air / oxygen, the factors of biochemical oxygen demand without nitrification and chemical oxygen demands needs to be considered.
  4. The operation and processing of the sewage system including:
    • Availability of chemicals recommended by manufacturer for chlorination, in sufficient quantities;
    • If the effluent is neutralized, it should be performed in accordance with manufacturer’s specifications;
    • The operation of the comminutor and inlet filter;
    • The vacuum system is available and operational, if applicable;
    • The return flow pipes of the sewage treatment unit are clear, if applicable;
    • The operation and maintenance of the comminutor;
    • The system is operated according to the manufacturer’s instructions (in the case of organic systems sufficient time from start up to allow for bacterial growth).
  5. Familiarization of the operation and maintenance of the sewage system. Key personnel involved in the operation of the system may be asked during the inspection if and how they were familiarized with the system. Routine maintenance and repair records of the system may also be checked to confirm that the maintenance manuals are followed properly and in compliance.

2.5 Expanded Inspection

An expanded inspection should be carried out in accordance with the Paris MoU procedures and guidelines. There are no additional requirements regarding the Polar code to follow during an expanded inspection.

3. FOLLOW-UP ACTION

3.1 Deficiencies warranting Detention

The following (non-exhaustive) list of deficiencies could be considered, taking into account the provisions of regulation IV/3, to be of such a serious nature that may warrant the detention of the ship involved:

  1. Absence of valid ISPP certificate;
  2. Any systems of the sewage treatment plant are out of order. This may include but is not limited to: the aeration system (no continuous supply of air), where applicable, and the liquor return system;
  3. Sewage discharged overboard directly without proper treatment by sewage treatment plant;
  4. Officers not familiar with the essential shipboard procedures relating to the prevention of pollution by sewage.
  5. Sewage treatment plant not approved by the Administration.

4. REPORTING

4.1 Codes

Code Deficiency
01119 International Sewage Pollution Prevention Certificate
14402 Sewage Treatment Plant
14403 Sewage Comminuting and disinfecting system
14404 Sewage Discharge Connection
14405 Crew training and familiarization
14499 Other (MARPOL – Annex IV)

[1] As defined in regulation. 1.10 of MARPOL A.IV

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