Section 11(1) in The Merchant Shipping (Prevention of Pollution by Sewage from Ships) Rules, 2010
(1)Subject to the provisions of rule 3, the discharge of sewage into the sea is prohibited, except under the following circumstances, namely ;-(a)the ship is discharging comminuted and disinfected sewage using such system as specified under clause (b) of rule 9 at a distance of more than three nautical miles from the nearest land, or sewage which is not comminuted or disinfected at a distance of more than twelve nautical miles from the nearest land ;Provided that the sewage that has been stored in holding tanks shall not be discharged instantaneously but at a moderate rate when the ship is en route and proceeding at not less than four knots:Provided further that the rate of discharge shall be approved by the Central Government, on the basis of standards developed by the International Maritime Organisation; or(b)the ship has in operation the sewage treatment plant to meet the operational requirements as specified under clause (a) of rule 9 and -(i)the test results of the plant are laid down in the ship's International Sewage Pollution Prevention Certificate; and(ii)the effluent shall not produce visible floating solids nor cause discolouration of the surrounding water.
