75 mm
1:50
750 mm
Appendix B ProPECC PN 1/23
1 in 12
No, bypass arrangements are not allowed unless well justified.
Grade 30/20
25 mm
Waste minimization should be practiced, and waste heat, metal, oil, and chemicals should be recovered wherever practicable.
1 in C
50 x 10 mm
Provisions should be made for future connections to public foul sewers.
Concrete pipe
150 mm
6500 (max.)
H3028/10A
H 3138B
A sampling point and an automatic flow measuring device with a non-resettable type totalizer.
Grade 1.4401
900 mm
150 mm
6500 mm
H3143B
25 mm
1:50
150 mm
DS1031
Discharge to foul sewers should be kept to a minimum to avoid unduly overloading the foul sewerage and to prevent pollution of the storm water systems.
1.6 m³
H3142B
50mm
BS4449
Authorised Persons (APs) are welcome to approach the EPD for discussion or clarification, preferably as early as possible in the planning stage of a project.
Transport interchange for open public petrol interceptor
October 22
H3134B
Not less than 2.3 m³ but not more than 41 m³.
At least 20 minutes
Soil replacement, mound system, or diversion of soakaway path
The drainage plan submission should include detailed drawings and design calculations, following the recommendations of the 'Code of Practice for Oil Storage Installations' published by the Building Authority.
225 mm
200 mm
BS EN ISO 1461: 2022
The description should indicate areas where water is used and wastewater is generated.
November 2002
No, surface water must not be connected to the tank.
Grade S275 to BS EN 10025
The gradient of the inlet pipe should be greater than 1 in 10.
It should be connected to the storm water drains via a petrol interceptor with storm water bypass.
No, grease traps are not required for bars and pantries where cooking will not be carried out.
The main drain of a swimming pool should be connected to storm water drains, except in Water Gathering Grounds where consultation with the Water Supplies Department is advised.
100 mm
Oct 22
H3028/8A
Detailed hydraulic and process calculations.
1800 mm.
100 mm
The velocity inside the pipes should not be greater than 0.2 m/s.
They should be located within roofed areas as far as possible.
For sewage treatment plants designed to cater for a peak flow of 3 times the daily average flow rate, it is recommended to provide two duty and one standby pumps in equalization tanks as far as practicable to limit the flow through the treatment units to within 1.5 times the daily average flow rate during off-peak periods.
Runoff should pass through a gully pit with necessary gratings to prevent objects from entering the storm water drains.
150 mm diameter concrete pipe
Environmental Protection Department Hong Kong
It can be calculated pro-rata.
Standby dosing pumps, a standby acid/alkali dosing system, and a pH sensor with visual alarm and graphical recorder.
DS1034
100 meters
1.5 meters
The minimum size for the cleaning hole is 200×200mm with a cover.
Sewage pump sumps should have a standby pump with a capacity not less than any of the duty pumps, and duty pumps should not operate more than 10 on-off cycles per hour.
1500 mm center to center
200 mm
A grease trap with a retention volume of 0.7 m³ should be provided unless the adequacy of a smaller grease trap can be demonstrated.
2:1.
6mm
To determine the absorption capacity of soil
Under section 40(1) and 41(1) of the Building (Standards of Sanitary Fitments, Plumbing, Drainage Works and Latrines) Regulations (Cap. 123I), foul water should be discharged to a foul sewer and surface water should be discharged via rainwater pipes to storm water drains.
A septic tank or other approved facility should be provided to dispose of foul water where there is no public sewer in the vicinity.
A sewage treatment plant submission should include all information required in the 'Guidelines for the Design of Small Sewage Treatment Plants'. The exact discharge location and effluent discharge standards should be checked with the EPD before commencing on design.
Proposals on effluent reuse should be discussed with the EPD at the early conception stage.
2.4
It should adequately address the fluctuations in wastewater flow and characteristics.
ProPECC PN 1/23
75 mm.
The minimum height (H) is 600mm and the maximum height is 1200mm. For kitchen floor areas ≥ 50m², H should be a minimum of 900mm.
30 meters
Polluted rainwater should be discharged to storm water drains after the removal of pollutants by appropriate facilities.
Drainage outlets in open areas subjected to wind-blown rain should be connected to storm water drains.
0.5 m³ per day per m² of kitchen floor area.
40 diameter of bar
550 x 550 mm.
94 litres per m² per day
A small sewage treatment plant is acceptable only where it is demonstrated that there is no viable alternative, including public sewerage, pumping mains to connect to public foul sewers, upgrading of existing sewerage, and the use of a septic tank and soakaway system for small rural populations.
The Technical Memorandum on Effluent Standards is available at the EPD’s website (http://www.epd.gov.hk).
Additional installations might be required to meet the standards given in the Technical Memorandum on Effluent Standards issued under section 21 of the Water Pollution Control Ordinance Cap.358.
No, overflow or bypass pipes are not allowed.
A standby alkali dosing system should be used to cater for overdosing of acid to alkaline wastewater.
No, disposal of commercial and industrial wastewater by injection into the ground (e.g. by soakaway pits) is not allowed.
Commercial and industrial wastewater should be pretreated, where necessary, to meet prescribed effluent standards.
They should be connected via a petrol interceptor that allows storm water bypass during peak flow periods.
Under section 90 of the Building (Standards of Sanitary Fitments, Plumbing, Drainage Works and Latrines) Regulations (Cap. 123I).
Every 6 months.
The booklet 'Guidance Notes on Discharges from Village Houses' published by EPD.
The design should follow the recommendations of the Practice Note for Authorized Persons and Registered Structural Engineers: 'Pollution from Industrial Buildings - Building (Standards of Sanitary Fitments, Plumbing, Drainage Works and Latrines) Regulation 90' (PNAP: APP – 46) published by the Building Authority.
Reinforced concrete grease traps should be designed as liquid retaining structures with maximum surface crack widths of 0.2 mm.
It should ensure that no leaked or spilled oil could escape from the site even in the event of a serious transformer failure, fire, and similar incidents. Contaminated rainwater and fire-fighting water should also be discharged via an adequately designed oil interceptor.
The design of septic tank and soakaway systems should meet the minimum requirements given in Appendix D. Drainage plan submissions should include separation distances between soakaway systems and nearby water bodies/structures, percolation test results, and detailed design calculations.
Subsoil drains of slopes and groundwater collection drains for basements should be connected to storm water drains.
The minimum diameter for inlet pipes is 100mm and for vent pipes is 75mm.
1.5 meters
The minimum clear opening size for the cover is 550×550mm.
The EPD generally sets effluent discharge standards with reference to the Technical Memorandum on Effluent Standards issued under Section 21 of the Water Pollution Control Ordinance.
Surface water drainage should be provided to discharge storm water off slopes and from open surfaces, and should be led to storm water drains via silt removal facilities.
The nature of the business should be included.
Seawater used for cooling air-conditioning plants should be discharged directly to the sea to avoid overloading the storm water drains.
Design parameters for nitrification, tertiary treatment, and nutrient removal should be well supported by relevant information, giving due regard to local influent characteristics and climatic conditions.
A minimum distance of 200mm is required between each level switch.
The sign should include the overall depth of the grease trap, liquid depth of the grease trap, a note that the grease trap needs cleaning when the top 200mm of liquid depth is occupied by grease, and warning signs and safety barriers should be erected around the manhole openings during cleaning and maintenance.
The volume is calculated as Volume = B (L1 + L2) H.
Drainage in covered carparks and covered lorry loading areas should be connected to foul sewers via petrol interceptors.
The horizontal pipe should not be longer than 10m. If this cannot be achieved, the gradient of the pipe should be increased and rodding eyes should be provided.
Drainage outlets in covered areas receiving wastewater should be discharged to foul sewers.
Amendments should be clearly marked or coloured on the drainage plans.
Details of an appropriate wastewater treatment facility, where necessary to meet prescribed effluent standards, should be included.
It should be discharged via a grease trap capable of providing at least 20 minutes retention during peak flow.
Drainage outlets of verandahs next to kitchens and utility rooms should be connected to foul sewers to prevent dwellers from discharging laundry or dishwasher wastewater through these outlets.
No, dilution is not allowed as a means of meeting effluent standards.
550 x 550 mm
