Rainwater and wastewater
Rainwater
Where possible, rainwater should be infiltrated on your own property or discharged locally into a body of water. The untargeted discharge of rainwater via the living soil zone into the groundwater does not constitute the use of water bodies in the sense of water law. A permit under water law is therefore not required for surface infiltration.
The water collected from precipitation from built-up or paved areas is called rainwater and falls under the generic term wastewater in terms of water law. In Aachen, the city of Aachen (the municipality responsible for wastewater disposal) is generally responsible for the proper disposal of wastewater. The obligation to dispose of wastewater can be transferred to the property owner if he can prove that the rainwater has been properly disposed of/discharged into a body of water/groundwater on his own property. The following options can be considered for the disposal of rainwater:
- Surface infiltration via the surface and living soil zone
- Swale infiltration via the activated soil zone of the swale
- Swale infiltration
- Infiltration trench/pipe infiltration
- Discharge into a body of water
A permit under water law must be applied for from the Lower Water Authority of the City of Aachen for infiltration and discharge into surface waters. In the case of infiltration systems, a corresponding soil survey is required in particular to prove the infiltration capacity. In many areas of Aachen, the geological conditions are not conducive to proper infiltration.
Polluted precipitation water, e.g. from parking lots, roads or industrial areas, must be treated before seepage or discharge into a body of water. A corresponding precipitation water treatment system (e.g. rainwater clarifier, retention soil filter basin) requires a water law permit.
A map of areas that cannot be properly drained can be viewed on the homepage in the online geoinformation system:
Competent authority:
Water pollution
On the basis of the current Environmental Alarm Directive, an on-call service has been set up at Aachen's lower environmental protection authority. Its aim is to ensure a rapid response and appropriate measures to contain environmental hazards, investigate and clarify the facts and inform all affected authorities and the public in good time in the event of damage or danger.
Who do I contact in the event of damage or hazards involving substances hazardous to the environment/water? We accept environmental alarm reports at the following environmental hotline number:
Environmental telephone
You can ask your questions about the environment here. The colleagues in the relevant specialist departments will be happy to help you.
Tel.: 0241 432-3666
Environmental alarm outside general working hours
Outside general office hours, the on-call service of the Lower Environmental Protection Authority (UUB) can be reached via the emergency control center of the professional fire department or by dialing 112 in an emergency:
Substances hazardous to water are, for example: acids, alkalis, salts, organic liquids (liquid manure, slurry, silage seepage), mineral oils, poisons, pesticides, metals, etc.
Typical accidents involving these substances are
- Overfilling with heating oil refueling
- Oil pollution on waterways
- Traffic accidents with fuel or cargo spillage
- Leaks in containers with water-polluting substances
Very important: Anyone who operates, maintains, repairs, cleans or checks a system and notices damage must report this damage immediately!
Content of a message:
- Name of the notifier
- Type of accident
- Place and time of the accident
- Type and quantity of the leaking substance
- Extent of the danger
- Already notified bodies
Other areas of application can be, for example, dead fish in a body of water and other discharges into a body of water that cause discoloration.
If you detect any water pollution/turbidity, please report this immediately to the responsible authority. Field service and monitoring of water bodies is one of the main tasks of a water authority, but it is not possible to keep a constant eye on the waterways in Aachen. We therefore thank you for your help.
Reports to the on-call service are generally made via the Aachen fire department. In addition, a few years ago the on-call service was extended to all areas of the environment (water, soil, waste, emissions) as a lower environmental protection authority.
Responsible authorities:
Substances hazardous to water
The Federal Ordinance on Installations for the Handling of Substances Hazardous to Water (AwSV) came into force on 01.08.2017. This federal ordinance replaces the previously applicable state ordinances.
It regulates...
- the classification of substances and mixtures according to their hazardousness
- the technical requirements that must be met by installations in which these substances and mixtures are handled, and
- the obligations of the operators of these systems.
Substances hazardous to water are, for example, oils, fuels, hydrocarbons, poisons, pesticides, etc. To protect the environment and health, these chemicals are tested and classified for their hazardousness.
An important criterion is the classification according to their water hazard; a distinction is made between three water hazard classes:
- WGK 1: slightly hazardous to water
- WGK 2: hazardous to water
- WGK 3: highly hazardous to water
Installations for handling substances hazardous to water must be planned, constructed and operated in such a way that there is no risk of water pollution (groundwater, surface water). These facilities include
- Storage, filling and transshipment facilities (LAU facilities, e.g. tank farms, oil and chemical storage facilities, filling stations, vehicle operations, but also heating oil storage facilities)
- Facilities for the manufacture, treatment and use of substances (HBV facilities, e.g. chemical industry, dry cleaners)
Very often, systems containing substances hazardous to water may only be installed and operated after a preliminary inspection by the authorities. You should therefore contact the employees of the lower water authority before setting up such a system.
Fuel oil storage
Whether for heating your own four walls or for drying grain in agriculture - heating oil is a popular energy source.
As practical as the chemical and physical properties of heating oil are for heat generation, they are a considerable source of danger for water, soil and groundwater. For this reason, heating oil is considered by law to be a substance hazardous to water and must be stored in a particularly safe manner. If heating oil leaks and gets into the soil or groundwater, this not only damages the environment, but also your wallet. This is because cleaning up the damage is expensive and the owner or operator of the system has to pay for it. They are responsible for the safe storage of the heating oil.
Competent authority:
Indirect discharge of wastewater into the public sewer system
Trade and industry produce wastewater that cannot be discharged into the public sewage system without further ado due to its contents. These substances lead to damage to surface waters, cleaning processes in the sewage treatment plant are impaired and the disposal of sewage sludge is made more difficult.
The requirements under water law that must be complied with are set out in the Annexes to the Wastewater Ordinance (AbwV), differentiated according to source areas. These include, for example, wastewater containing mineral oil, metalworking and dental treatment. The aim is to reduce the concentration/load to such an extent that the above-mentioned impairments do not occur, provided that the relevant state-of-the-art processes are adhered to. In some cases, this is only possible with a special wastewater treatment plant.
An indirect discharge of wastewater is subject to the approval of the lower water authority if the wastewater originates from one of the areas of origin listed in the Wastewater Ordinance (AbwV).
If a wastewater treatment plant is required in addition to compliance with limit values from the Wastewater Ordinance, plant construction and operation must also be approved by the lower water authority.
Commercial/industrial wastewater
The discharge of wastewater into public wastewater systems (indirect discharge) requires the approval of the competent authority if the wastewater is subject to requirements for the place where the wastewater is produced or before it is mixed (Section 58 WHG).
In addition to the provisions of water law (WHG/LWG), there are also the statutory provisions, the drainage statutes of the City of Aachen.
Monitoring of indirect dischargers
The discharge of wastewater into public wastewater systems (indirect discharge) requires the approval of the competent authority if the wastewater is subject to requirements for the place where the wastewater is produced or before it is mixed (Section 58 WHG).
In addition to the provisions of water law (WHG/LWG), there are also the statutory provisions, the drainage statutes of the City of Aachen.
The approval notice specifies self-monitoring based on the parameters to be monitored in the Wastewater Ordinance. In addition to this monitoring, official monitoring is carried out on the basis of the Wastewater Ordinance and the drainage statutes of the City of Aachen. For this purpose, the City of Aachen, Department of the Environment, has purchased a specially equipped, purely electric sampling vehicle, as well as explosion-proof devices for monitoring the wastewater in the sewer. An indirect discharger register forms the basis of this monitoring concept. The wastewater samples taken are analyzed in a certified external laboratory. If discharge parameters are not complied with, the lower water authority initiates regulatory proceedings against the discharger.
Competent authority: