Sewerage and Drainage Act
(Chapter 294, Sections 72 and 74)
Sewerage and Drainage (Trade Effluent) Regulations
Rg 5
G.N. No. S 170/1999

REVISED EDITION 2007
(15th May 2007)
[1st April 1999]
Citation
1.  These Regulations may be cited as the Sewerage and Drainage (Trade Effluent) Regulations.
Definitions
2.  In these Regulations, unless the context otherwise requires —
“blood waste” includes human blood, animal blood and any fluid, matter or material which is contaminated with blood;
“grease trap” means any interceptor, arrestor, tank or pit situated above or under the ground which allows culinary wastewater to cool and the grease therein to be separated from the wastewater;
“infectious disease” means any disease —
(a)specified in the First Schedule to the Infectious Diseases Act (Cap. 137); or
(b)which is caused, or is suspected to be caused, by a micro-organism or any agent of disease and is capable of transmission by any means to human beings or animals;
“infectious waste” means any waste which contains or may produce pathogens of an infectious disease and includes —
(a)cultures and stocks of agents of the infectious disease from a laboratory;
(b)in relation to a person who has been diagnosed as having or suspected to have the infectious disease, or who has died whilst being diagnosed as having or suspected to have the infectious disease —
(i)any waste from the person or the body of the person, as the case may be;
(ii)any waste from a surgery performed on the person or autopsy performed on the body of the person, as the case may be; and
(iii)any fluid, matter or material that has come into contact with the person or the body of the person, as the case may be; and
(c)in relation to an animal which is inoculated with an agent of the infectious disease, or which has been diagnosed as having or suspected to have the infectious disease, or which has died whilst being diagnosed as having or suspected to have the infectious disease —
(i)any waste from the animal or the body of the animal, as the case may be;
(ii)any waste from a surgery performed on the animal or autopsy performed on the body of the animal, as the case may be; and
(iii)any fluid, matter or material that has come into contact with the animal or the body of the animal, as the case may be;
“organic sludge” means organic matter in trade effluent which has a minimum solid content of 3% by weight or a maximum moisture content of 97% by weight.
Lawful discharge into public sewer, etc.
3.—(1)  The Board may, by notice in writing, require the owner of any premises to cause all trade effluent from those premises to be discharged into a public sewer in accordance with these Regulations.
(2)  A discharge of trade effluent shall be lawful for the purposes of section 16(4) of the Act if the discharge is —
(a)made in accordance with a notice referred to in paragraph (1); or
(b)made into a trade effluent treatment plant in accordance with these Regulations.
Approval for discharge into public sewer, etc.
4.—(1)  An application for approval to discharge trade effluent into a public sewer or any drain-line or sewer communicating with a public sewer referred to in section 16(1) of the Act shall be in such form as the Board may require.
(2)  The applicant shall, in his application, furnish to the Board —
(a)particulars of the trade, manufacture, business or building construction carried on or to be carried on by him and in the course of which the trade effluent is wholly or partly produced or of which the trade effluent is the waste or refuse;
(b)details of all the processes or operations employed or to be employed by him to produce the final products of the trade, manufacture, business or building construction;
(c)particulars of all the raw materials and chemicals used or to be used in the processes or operations;
(d)details of the layout of all the machinery, plant and equipment used or to be used in the premises in which the trade, manufacture, business or building construction is being or is to be carried on, as the case may be;
(e)an estimate of the amount of water consumed or used or to be consumed or used in the trade, manufacture, business or building construction;
(f)particulars of the physical, organic and chemical nature of the trade effluent; and
(g)such other information relating to the trade effluent and the discharge thereof as the Board may require.
(3)  The Board may, in granting any approval referred to in paragraph (1), impose such conditions as it thinks fit.
(4)  Where a person has been granted any approval referred to in paragraph (1), he shall notify the Board in writing, within 14 days of any change in —
(a)any process or operation employed by the person in paragraph (2)(b); or
(b)the layout of the machinery, plant and equipment used by the person in paragraph (2)(d),
which affects the amount or the physical, organic or chemical nature of the trade effluent discharged.
(5)  Any approval referred to in paragraph (1) —
(a)may be revoked or suspended for any period by the Board without assigning any reason; and
(b)shall cease to be valid when the person granted the approval fails to comply with these Regulations or any condition imposed under paragraph (3).
Pre-treatment plant, monitoring and control devices, etc.
5.—(1)  Any person who discharges trade effluent into any sewerage system shall, in connection with such discharge, install such sampling test points, inspection chambers, measuring devices, and recording and other apparatuses as the Board may require.
(2)  Any person who discharges trade effluent into any sewerage system shall install a pre-treatment plant if the Board so requires and shall —
(a)use or operate the plant to treat trade effluent before discharging the trade effluent into the sewerage system; and
(b)maintain the plant in an efficient condition at all times.
Installation of grease trap
6.—(1)  Any person who discharges trade effluent into any sewerage system shall, in connection with the discharge, install a grease trap, as the Board may require.
(2)  The person referred to in paragraph (1) shall ensure that the grease trap is maintained from time to time as the Board may, by notice in writing, require.
Particulars to be furnished
7.  Any person who discharges trade effluent into a sewerage system shall, at such times as the Board may require, submit particulars of —
(a)the amount of water consumed or used for the purposes of any trade, manufacture, business or building construction carried on by him and in the course of which the trade effluent is wholly or partly produced or of which the trade effluent is the waste or refuse;
(b)the physical, organic and chemical nature of the trade effluent;
(c)the raw materials and chemicals used in the trade, manufacture, business or building construction and the direction of the flow of any liquid or the trade effluent from or produced by any machinery, plant or equipment used in the trade, manufacture, business or building construction; and
(d)such other matters relating to the trade effluent and the discharge thereof as may be required by the Board.
Nature and type of trade effluent to be discharged
8.—(1)  No trade effluent other than that of a nature or type approved by the Board shall be discharged into any public sewer.
(2)  The temperature of the trade effluent shall not exceed 45° Celsius at the point of its entry into any public sewer.
(3)  The pH value of the trade effluent shall not be less than 6 nor more than 9 at the point of its entry into any public sewer.
(4)  The caustic alkalinity of the trade effluent shall not be more than 2,000 milligrams of calcium carbonate per litre at the point of its entry into any public sewer.
(5)  Any trade effluent shall be treated before it is discharged into a public sewer if the Board so requires.
Trade effluent to be free of certain substances
9.  The trade effluent discharged into a public sewer shall not contain any of the following substances:
(a)any toxic industrial waste specified in the first column of the Schedule to the Environmental Public Health (Toxic Industrial Waste) Regulations (Cap. 95, Rg 11);
(b)calcium carbide;
(c)petroleum spirit or other inflammable substance;
(d)any organic compound specified in the First Schedule;
(e)any substance that either by itself or in combination or by reaction with other waste or refuse may give rise to any gas, fume, odour or substance which is or is likely to be a hazard to human life, a public nuisance, injurious or otherwise objectionable, or which prevents or is likely to prevent entry into the public sewer by workmen maintaining or repairing it;
(f)yeast, spent or unspent molasses, crude tar, tar oil, crude oil, carbon disulphide, hydro-sulphide and poly-sulphide;
(g)any radioactive material;
(h)any waste or refuse liable to form a viscous or solid coating or deposit on any part of the public sewer or sewerage system;
(i)any excessively discolouring substance;
(j)any substance of a nature or quantity which is likely, either alone, in combination with or by interaction with another substance —
(i)to cause a fire or an explosion in the public sewer or a sewerage system to which the public sewer is connected;
(ii)to cause damage to the public sewer or a sewerage system to which the public sewer is connected; or
(iii)to interfere with —
(A)the proper working of a sewerage system to which the public sewer is connected, or any facility, machinery or equipment related or connected to the sewerage system;
(B)the proper working of any facility, machinery or equipment which treats sewage from the public sewer for reuse;
(C)any process of treating trade effluent or other waste or refuse from the public sewer; or
(D)any process of treating sewage from the public sewer for reuse;
(k)any pesticide, fungicide, herbicide, insecticide, rodenticide or fumigant;
(l)blood waste;
(m)infectious waste.
Maximum concentrations of certain substances
10.—(1)  Any trade effluent discharged into a public sewer shall not —
(a)contain any of the substances listed in the Second or Third Schedule in concentrations greater than those specified therein;
(b)have a 5-day Biochemical Oxygen Demand at 20° Celsius (referred to in this regulation and regulation 11 as BOD) greater than 400 milligrams per litre of the trade effluent;
(c)have a Chemical Oxygen Demand (referred to in this regulation and regulation 11 as COD) greater than 600 milligrams per litre of the trade effluent; or
(d)have Total Suspended Solids (referred to in this regulation and regulation 11 as TSS) greater than 400 milligrams per litre of the trade effluent.
(2)  The Board may stipulate —
(a)the maximum volume and quantity of a substance which may be discharged into a public sewer under this regulation; and
(b)the maximum rate at which the substance may be so discharged.
(3)  Where the Board stipulates the maximum volume and quantity of a substance which may be discharged into a public sewer under this regulation and the maximum rate at which the substance may be so discharged, no person who has been informed by the Board by notice in writing of the volume, quantity or rate may discharge the substance into a public sewer in a volume or quantity or at a rate in excess of that so stipulated.
Permission required to discharge certain trade effluent
11.—(1)  Subject to paragraph (2), any person may, notwithstanding regulation 10, with the prior permission of the Board discharge into any public sewer trade effluent containing BOD or TSS greater than 400 milligrams per litre of the trade effluent or COD greater than 600 milligrams per litre of the trade effluent.
(2)  No person shall discharge into any public sewer trade effluent containing —
(a)BOD greater than 6,000 milligrams per litre of the trade effluent;
(b)TSS greater than 6,000 milligrams per litre of the trade effluent; or
(c)COD greater than 10,000 milligrams per litre of the trade effluent or 3 times the concentration of BOD in the trade effluent, whichever is the lower.
(3)  Any person may, with the prior permission of the Board, dispose of organic sludge at any sewage treatment works specified by the Board.
(4)  The Board may, in granting any permission under paragraph (1), (2) or (3), impose such conditions as it thinks fit.
(5)  An application for the permission of the Board —
(a)under paragraph (1) shall be accompanied by the appropriate fee computed in accordance with the scale set out in the Fourth Schedule; and
(b)under paragraph (3) shall be accompanied by a fee of $7 per cubic metre or part thereof of organic sludge.
(6)  In computing the fee payable by any person under paragraph (5), any fraction of a dollar shall be ignored.
Method of analysis and collection of samples
12.—(1)  For the purposes of these Regulations, trade effluent discharged into a public sewer or any drain-line or sewer to which the public sewer is connected shall be analysed in accordance with the latest edition of “Standard Methods for the Examination of Water and Wastewater” published jointly by the American Public Health Association, the American Water Works Association and the Water Environment Federation of the United States, as amended from time to time, or in accordance with such other method of analysis as the Board thinks fit.
(2)  Trade effluent samples required by the Board shall be collected from any sampling test point or inspection chamber installed under regulation 5(1), or any drain-line or sewer to which a public sewer is connected, as determined by the Board.
Payment of fees
13.—(1)  The fees payable under these Regulations are inclusive of the goods and services tax chargeable under the Goods and Services Tax Act (Cap. 117A) on the services in respect of which such fees are payable.
(2)  The fees payable under these Regulations shall be paid to the Board by interbank GIRO or such other means as the Board may from time to time specify.
Penalty
14.  Any person who contravenes any provision of these Regulations shall be guilty of an offence and shall be liable on conviction to a fine not exceeding $5,000 and, in the case of a continuing offence, to a further fine of $500 for every day or part thereof during which the offence continues after conviction.