Wastewater treatment in sparsely populated areas

A property situated in a sparsely populated area must provide an account of the wastewater system. It is possible to apply for an exemption from wastewater treatment requirements. You need an action permit in order to build or change a wastewater system.

A property not connected to a wastewater sewer must comply with the requirements set for it for the treatment of domestic wastewater. Wastewater must be treated in such a way that it does not cause harm to health or cause the risk of environmental pollution.

The property must provide a written account of the wastewater treatment system.

It is possible to apply for an exemption from wastewater treatment requirements. Permission for exemption can be granted on the basis of the property owner's age, health or financial situation, for example. An exemption can only be granted if insufficient wastewater treatment does not cause a risk of environmental pollution.

You need an action permit in order to build or change a wastewater system.

Apply for permission for exemption from the wastewater treatment requirements.

Apply for permission for exemption from the wastewater treatment requirements electronically from the City of Helsinki's Environmental Services via Lupapiste. Permission for exemption can be granted for a maximum of five years at a time.

Additional information

- Appendix 1: A layout plan (e.g. at a 1:500 scale), showing the locations of buildings and wastewater treatment systems as well as their distances to ditches, waterways, domestic water wells and boundaries

- Appendix 2: Description of the wastewater system

- Appendix 3A: Small amount of wastewater

- Appendix 3B:Connection to the sewer network

- Appendix 3C:High age of the property owner and other situations in life

- Appendix 3D: Long-term unemployment or illness of the property owner or other similar social performance impediment

Use the online service

Apply for permission for exemption from the wastewater treatment requirements.

Requires authentication.

Provide an account of the property’s wastewater system

Every property must provide a written account of its wastewater treatment system. Fill out the account, keep it at the property and present it to the supervisory authority when requested.

Go to the account of the wastewater system (pdf)

Go to the account of the wastewater system (docx)

Building or changing a wastewater system 

If you build a new property-specific wastewater system or change an existing system, you need an action permit. Have a qualified designer involved in the project in good time, who has the necessary expertise to draw up the wastewater system plan and other documents. 

When you complete an action permit application, you will get more detailed information about the necessary appendices via Lupapiste. In general, you need at least the following appendices:

  • power of attorney
  • construction drawings
  • special plans for water supply and sewage systems
  • wastewater system plan (pdf, 1 Mb)
  • system’s operating and maintenance instructions
  • soil scientist’s statement if purified wastewater is absorbed into the soil

Read more detailed instructions:  Action permit for domestic wastewater treatment equipment in sparsely populated areas (pdf, 1 Mb)

Read more about the action permit or  Apply for an action permit electronically via Lupapiste (Link leads to external service)

Frequently asked questions

In a sparsely populated area, small amounts of domestic wastewater from a residential property can be discharged into the ground untreated if it does not contain wastewater from a flush toilet and if the amount of wastewater is small and does not pose a risk of environmental pollution.

The amount of water is considered to be small if domestic water is carried or led through a temporary water pipe or if the property is modest in terms of water use and equipment, for example. Contact us via Lupapiste’s Ask for advice function if you are not sure whether you need a permit.

The precondition for granting an exemption is that, in view of the use of the property, the environmental burden is considered significantly small compared to the burden caused by untreated wastewater, or the measures required to improve the treatment system as a whole can be considered unreasonable for the owner of the property, due to the high costs and technical demands involved.

When assessing the unreasonableness of the measures from the property owner’s point of view, the following is taken into account:

1) the location of the property in the area intended to be extended to the sewer network

2) the high age of the owner of the property and those permanently resident on the property and other similar special factors related to the situation in life

3) Long-term unemployment or illness of the property owner or other similar social performance impediment.

An exemption can only be granted if wastewater treatment on the property is arranged in such a way that it does not cause a risk of environmental pollution.

The permit granted expires if the use of the property changes so that the environmental burden increases or the ownership or management of the property changes.