MEPC.157(55): Sewage Discharge Rate Standard
MEPC.157(55) sets the maximum discharge rate of untreated sewage from holding tanks at 1/200,000 of swept volume, the rate Annex IV Regulation 11 requires.
Resolution MEPC.157(55), adopted 13 October 2006, is the IMO recommendation on standards for the rate of discharge of untreated sewage from ships. It sets the maximum permissible rate at 1/200,000 of the swept volume, expressed as DRmax = 0.00926 x V x D x B cubic meters per hour, averaged over 24 hours with an hourly excess of no more than 20%. Since MEPC.164(56), in force 1 December 2008, MARPOL Annex IV Regulation 11.1.1 requires the rate to be approved by the Administration on IMO standards.
The full article will cover approval at maximum summer draught and service speed, secondary rates, calibrated fixed-rate pumps, the crew check before discharge, and the no-dilution rule.