Water: groundwater collection, disposal standards, clean-up fees

1. Types of supply and disposal

Most Brussels companies use distribution water and dispose of water in the sewer. In this case, the regulation below is applicable.

Two other cases should be noted:

  • If you plan to use groundwater collection (for a car wash, for example), two authorisations are required: a collection authorisation (FR) and an environmental permit.

  • If you want to dispose of your waste water in surface water (in the canal for example), in groundwater, in artificial rainwater run-off channels, or in the ground, the regulation is very strict.

For more information on these two examples, please contact Environment Brussels or the impulse.brussels environment advisors.

The Environment Brussels website provides some general information on water (FR) and targeted information for certain activity sectors (FR). 

2. Some important points

To understand your regulatory obligations, it is important to know that waste water falls into one of two categories:

Domestic waste water 

... if it comes exclusively from sanitary installations, kitchens, cleaning of buildings (residences, offices, shops, schools, restaurants, hotels, etc... that is to say places not presenting a particular risk), laundry done at home or in a coin-operated laundry, washing bicycles, car washes (max. ten vehicles per day), rainwater, and water from factories, workshops or depots, or laboratories employing less than seven people, unless the authority issuing disposal authorisation (see the point below) deems that the waste water presents too many risks.

Industrial waste water

... in all other cases. 

3. Authorisation for disposing of waste water in sewers

In theory, all disposal of waste water should be subject to authorisation.

In practice,

  • domestic waste water disposed of in the sewer does not require the issue of specific authorisation.
  • industrial waste water disposed of in the sewer must be covered by an authorisation.

There are two main situations:

  • either you are the holder of an environmental permit and it includes authorisation to dispose of waste water;
  • or you are the holder of an old permit with a short validity period, and you need to apply for supplementary authorisation from Environment Brussels.

4. Standards for disposing of waste water in sewers

4.1. Three possible scenarios

In practice, there are 3 different scenarios:

  • general standards set out below if your environmental permit doesn't mention them and your activity is not the subject of sector standards.  These standards are described in detail below.
  • sector standards if they apply to your activity. Of the sixty sectors (FR) concerned by specific waste water disposal standards, thirty can be found in Brussels.  This applies to laundries, laboratories and butchery or poultry slaughterhouses. 
    Please note that if a parameter is not defined in the related sector standards, the general standard is then applied to this parameter.
    In addition, some sectors such as car repair workshops, dry cleaners and service stations are the subject of specific legislation which can also impose obligations related to the water issue.
    Do not hesitate to contact the environment advisors at impulse.brussels in order to understand how these standards work. 

4.2. General standards

a) applicable to the discharge of domestic and industrial waste water

The following is prohibited in public sewers:

  • disposing of or pouring objects, materials, or solid waste subject to mechanical grinding or water containing such materials;
  • allowing polluted liquids or pollutants to run into them, or introducing gases.

It is also prohibited to discard solid or liquid material in a place where they may, due to a natural phenomenon, be found in these same waters.

b) the discharge of domestic waste water

This waste must not contain:

  • textile fibres, plastic packaging, solid household waste (organic or not);
  • mineral oils, flammable products, volatile solvents;
  • other materials extractable from petroleum ether, which is to say fats with a content greater than 0.5 g/l.
  • other substances likely to make sewer waters toxic or dangerous.

c) the discharge of industrial waste water

These discharges are authorised under the following conditions:

  • pH: between 6 and 9.5;
  • temperature: less than or equal to 45°C;
  • suspended matter must not exceed 1 cm and 1 g/l, or affect the operation of lift and purification stations;
  • must not contain flammable dissolved gas or explosives, or products likely to cause the release of such gases;
  • does not cause emanation harming the environment;
  • materials extractable from petroleum ether, which is to say fats: £ 0.5 g/l;
  • must not contain substances likely to present a danger for maintenance personnel working for the sewers and purification stations, a deterioration or obstruction of the channels, a hindrance to the operation of the purification station, or backflow installations or significant pollution to the receiving surface water.

5. Fee for the clean-up of waste water disposed of in the sewer

Waste water disposed of in the sewer is treated, in part, in one of the two public purification stations in the Brussels-Capital Region.

In theory, everyone should pay a fee proportional to the quantity of each type of pollutant discarded.  Therefore, everyone should measure and analyse their waste water. This is not realistic even if this option is left open to each company.

In practice: 

  • either your waste water is considered as domestic (sectors not considered in the water legislation), and you will receive a water bill from Hydrobru including the regional fee for sanitation services.

    Note: the assumption is that all water you consume is disposed of in the sewer.  If this is not the case, you can contact the environment advisors at impulse.brussels to see how to claim a partial refund of the fee.
  • or your waters could be industrial (sectors included in the water legislation), and in this case you will receive your water bill from Hydrobru(including the basic regional fee) but you will also receive a form to be sent to Environment Brussels and an explanatory note.  At the end of this note you will find the sectors generating industrial waters.
    After examining your application, Environment Brussels will tell you:
    • either that the entirety of your waste water is considered to be domestic because your company employs less than seven people and there is no specific water pollution risk.  In this case, you don't have to pay anything further, and you will be refunded a portion of the fee if the water sampled in the network is not at all found in the sewers.

    • or that your waste water is, at least in part, industrial and that, based on a theoretical calculation, the pollutant load is less than 20 million units.  In this case, a one-off fee will be calculated based on your business sector and the volume of this load. This fee, a deduction made from the basic fee that you have already paid to Hydrobru, will be invoiced to you.

    • or that your waste water is, at least in part, industrial and that, based on a theoretical calculation, the pollutant load is greater than or equal to 20 million units. In this case, analyses will be requested from you and the additional fee due or the partial refund will be based on the actual pollutant load in your waste water. 
Updated 28/07/2017
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