Wastewater in sparsely populated areas

The property’s wastewater system must meet the requirements for the treatment efficiency, method and distances to wells, etc. The requirements are set out in the Environmental Protection Act, Espoo’s environmental protection regulations and the Government Decree on Treating Domestic Wastewater in Areas Outside Sewer Networks.

In Espoo, wastewater containing toilet wastewater must not be absorbed into the soil, even if it has been treated. In addition, in Class 1 groundwater areas, toilet wastewater must be led into a leak-proof tank and no domestic wastewater can be absorbed into the soil.

The wastewater system must meet the strict treatment requirement close to water systems and in Class 1 groundwater areas. In other areas, it is sufficient to meet the basic-level treatment requirement.

Basic-level treatment requirement: 80% of organic matter, 70% of total phosphorus and 30% of total nitrogen must be removed from wastewater. Strict treatment requirement: 90% of organic matter, 85% of total phosphorus and 40% of total nitrogen must be removed from wastewater.

The treatment requirement applies to blackwater and greywater calculated together. If a dry toilet is used or blackwater is led into a cesspool, the need for greywater treatment is minor. Blackwater is wastewater from toilets. Greywater is other domestic wastewater (from the kitchen, shower, washing machine, dishwasher, etc.).

You can use the Espoo Map Service(external link, opens in a new window) to check whether your property is located near a water system or in a groundwater area. To display groundwater areas, click the icon on the left to select the information shown on the map -> Ympäristö -> Pohjavesialueet. You can see the class of the area in the same way. You can measure the distance to water systems using the tool on the right side.

Note! A leaching field/bed is not the same as soil filtration. In a leaching field/bed the water is absorbed and disappears into the ground. In soil filtration the filtrated water is gathered with pipes and lead further.

1. Closed dry toilet (including composting of urine and liquids), no running water, or water supply but no water fixtures, such as shower, hot water boiler, washing machine or dishwasher

2. Blackwater into a cesspool, or a closed dry toilet (including composting of urine and liquids), and greywater into leaching field/bed or otherwise absorbed into the soil

3. Blackwater into a cesspool, or a closed dry toilet (including composting of urine and liquids), and greywater treated by means of a small treatment plant, greywater filter or soil filtration, basic-level treatment requirement

4. Blackwater into a cesspool, or a closed dry toilet (including composting of urine and liquids), and greywater treated by means of a small treatment plant, greywater filter or soil filtration, strict treatment requirement

5. Blackwater into a cesspool, or a closed dry toilet (including composting of urine and liquids), and greywater treated in a precipitation tank

6. Blackwater and greywater into a cesspool

7. Blackwater and greywater into leaching field/bed or otherwise absorbed into the soil

8. Blackwater and greywater treated by means of a small treatment plant or soil filtration and discharged into a ditch or water system, basic-level treatment requirement

9. Blackwater and greywater treated by means of a small treatment plant or soil filtration and discharged into a ditch or water system, strict treatment requirement

10. Blackwater and greywater treated by means of a small treatment plant or soil filtration and then absorbed into the soil

11. Blackwater and greywater treated in a precipitation tank

The wastewater systems of properties located near water systems or in groundwater areas must have complied with the current requirements as of 31 October 2019. The deadline applies to buildings located:

• max. 100 m from water systems or the sea
• in a Class 1 or 2 groundwater area. (You can use the Espoo Map Service (external link, opens in a new window)to check whether your property is located near a water system or in a groundwater area. To display groundwater areas, click the icon on the left to select the information shown on the map -> Ympäristö -> Pohjavesialueet. You can see the class of the area in the same way. You can measure the distance to water systems using the tool on the right side.)

In other areas, the wastewater system must be upgraded when any of the following is carried out on the property:

• Construction of a flush toilet, or repair and alteration work on water and sewer equipment subject to a permit and involving the replacement or repair of the entire system; or
• Repair and alteration work that is comparable to the construction of a building and requires a building permit.

In the table below, the compliant treatment methods are: 1, 4 and 6 in Class 1 groundwater areas; 1, 2, 4, 6 and 9 in shore areas max. 200 m from water systems or the sea; and 1, 2, 3, 4, 6, 8 and 9 in other areas. Treatment methods to be changed during renovation: 7 and 10 in Class 2 groundwater areas; 3, 5, 7, 8, 10 and 11 within 100–200 m of water systems; and 5, 7, 10 and 11 in other areas. Treatment methods to be changed immediately (but if the building permit was obtained after 2003, changed during renovation): 2, 3, 5, 7, 8, 9, 10 and 11 in Class 1 groundwater areas; 5 and 11 in Class 2 groundwater areas; and 3, 5, 7, 8, 10 and 11 max. 100 m from water systems.

Note! A leaching field/bed is not the same as soil filtration. In a leaching field/bed the water is absorbed and disappears into the ground. In soil filtration the filtrated water is gathered with pipes and lead further.

1. Closed dry toilet (including composting of urine and liquids), no running water, or water supply but no water fixtures, such as shower, hot water boiler, washing machine or dishwasher
   
    
2. Blackwater into a cesspool, or a closed dry toilet (including composting of urine and liquids), and greywater into leaching field/bed or otherwise absorbed into the soil
   
    
3. Blackwater into a cesspool, or a closed dry toilet (including composting of urine and liquids), and greywater treated by means of a small treatment plant, greywater filter or soil filtration, basic-level treatment requirement
   
    
4. Blackwater into a cesspool, or a closed dry toilet (including composting of urine and liquids), and greywater treated by means of a small treatment plant, greywater filter or soil filtration, strict treatment requirement
   
    
5. Blackwater into a cesspool, or a closed dry toilet (including composting of urine and liquids), and greywater treated in a precipitation tank
   
    
6. Blackwater and greywater into a cesspool
   
    
7. Blackwater and greywater into leaching field/bed or otherwise absorbed into the soil
   
    
8. Blackwater and greywater treated by means of a small treatment plant or soil filtration and discharged into a ditch or water system, basic-level treatment requirement
   
    
9. Blackwater and greywater treated by means of a small treatment plant or soil filtration and discharged into a ditch or water system, strict treatment requirement
   
    
10. Blackwater and greywater treated by means of a small treatment plant or soil filtration and then absorbed into the soil
    
     
11. Blackwater and greywater treated in a precipitation tank

According to Espoo’s environmental protection regulations, the discharge point for treated wastewater and wastewater systems must be at a sufficient buffer distance from sensitive water systems (does not apply to cesspools). The recommended minimum buffer distances are as follows, unless otherwise reliably specified:

• water abstraction site 200 m
• domestic water well 20–50 m
• water system, sea, streamlet and spring 10–30 m
• road and boundary of the property 5 m
• groundwater level in soil absorption system 1 m
• groundwater level in soil filtration 1 m

Blackwater is wastewater from toilets. Greywater is other domestic wastewater (from the kitchen, shower, washing machine, dishwasher, etc.).

Wastewater must not end up directly in a water system or the sea, even if it is diluted or in small quantities, such as water carried to a lakeside sauna. Wastewater must be absorbed into the soil or otherwise treated.

Keep blackwater and greywater separate

The majority of nutrients in domestic wastewater are in urine: 80% of the nitrogen and 50% of the phosphorus. Faeces contain 10% of the nitrogen and 30% of the phosphorus, and faecal pathogens threaten wells. Greywater only contains organic matter and few nutrients.

Wastewater treatment is easier if blackwater and greywater are not mixed. The treatment efficiency requirement applies to blackwater and greywater calculated together. When using a dry toilet or collecting blackwater in a cesspool for delivery to a wastewater treatment plant, only organic matter must be removed from greywater, and some phosphorus must be removed with the strict treatment requirement. In addition, absorption into the soil is a permissible treatment method.

When you use a dry toilet, there is no nutrient-rich toilet wastewater and the need for greywater treatment is minor. Information about dry toilets and composting of toilet waste is available on the website of the Global Dry Toilet Association of Finland(external link, opens in a new window).

Dry toilet waste must only be composted in a composter or toilet unit that has been designed for this purpose and is closed, well-ventilated and protected against run-off into the soil and protected from pests. Faecal waste must be composted for at least one year, starting from the time when fresh toilet waste is no longer added to the compost. Read more in the waste management regulations of the Helsinki Metropolitan Area and Kirkkonummi.

In some dry toilets, urine or leachate is collected separately. They are rich in nutrients and faecal pathogens. Therefore, they must be absorbed in litter and composted for one year like the other contents of the dry toilet. If urine is collected before it is mixed with faeces, it is free of pathogens and can therefore be used as a fertiliser in diluted form after 1 month of aging. 

If urine or leachate is led into the greywater treatment system, it is subject to the requirements of the blackwater treatment system, since the liquid includes lots of nutrients and faecal pathogens.

Already at the planning stage, take into account the necessary maintenance of wastewater systems on islands with no road connection. The precipitation tanks of the systems need to be emptied as often as annually, so choose a system you can take care of yourself. The Helsinki Region Environmental Services Authority (HSY) does not empty tanks on islands without a road connection.

Sludge drainage must be obtained from HSY in Espoo in accordance with the waste management regulations of the Helsinki Metropolitan Area and Kirkkonummi. This regulation has been issued in order to allow the comprehensive monitoring of drainage.

Minimum drain intervals for tanks

• precipitation and sludge tanks 1 year
• greywater sludge tanks 3 years
• cesspools as necessary

The treatment system to be drained must be located and its location and the road there maintained such that drainage can be carried out without hindrance.

Self-treatment of sludge is allowed when all of the following conditions are met:

• The amount of sludge from a small treatment plant or other similar wastewater treatment system, or the amount of sludge in the greywater precipitation tank, is minor. The amount of sludge is minor if it is less than 40 litres per drainage and less than 160 litres per year.
• Sludge containing faecal waste from small treatment plants must only be composted in a composter or toilet unit that has been designed for this purpose and is closed, well-ventilated and protected against run-off into the soil and protected from pests. Faecal waste must be composted for at least one year, starting from the time when fresh toilet waste is no longer added to the compost.
• Written notification of self-treatment has been made to HSY.

You should prepare for the construction of a water supply and sewerage network in your area, since there is an obligation to join the network. It is advisable to place your own wastewater system on the property such that the pipes coming from the buildings are easy to connect to the municipal network. The network is usually built alongside roads. Extensions to the network are planned and decided by the Public Works Department. The latest plans are described in the Water services development plan 2021–2030.

The Union of Finnish Water Protection Associations’ Jätevesiopas website(external link, opens in a new window) contains a lot of information about wastewater systems, their maintenance and construction.

The website of the Water Protection Association of the River Vantaa and Helsinki Region(external link, opens in a new window) contains a lot of information about wastewater systems, their maintenance and construction, and contact information for local designers.

The Finnish Environment Institute’s treatment plant page(external link, opens in a new window) presents various wastewater treatment facilities and methods as well as the results achieved.

You can apply for an exemption from the deadline for renovating your property-specific wastewater system. An exemption only needs to be applied for if the system does not comply with the requirements of the Environmental Protection Act and the building is located less than 100 metres from a water system or in class 1 groundwater area. In other areas, there is no need to renovate the wastewater system until a flush toilet is built or a full renovation is made.

Under “Requirements for wastewater systems in sparsely populated areas in Espoo”, you will find additional information on which systems meet the requirements in which area.

The Environment and Building Control Department may grant an exemption from the deadline for renovation upon application if any of the following conditions are met:

• The volume of wastewater is very small.
• The water supply and sewerage network is soon to be extended to the area of the property.
• The costs are unreasonable for the property owner.

The exemption is granted for a limited period of not more than five years at a time. Additional information can be found in the application forms.

The permit will lapse if the use of the property changes in such a way that the load increases or if changes occur in the right of ownership or possession of the property.

You can apply for an exemption from the City of Espoo’s environmental protection regulations only if the system meets the basic-level treatment requirement, but not the strict treatment requirement or the soil absorption ban.

A fee of €110 is charged for the processing of the application according to the environmental protection authority’s rates.

• Complete the application form. The application form and appendices are not accessible. If this causes difficulties, please contact the Environment and Building Control Department.
• Complete Appendix 2 (docx, 61 kB) (description of the wastewater system). If the property has several wastewater systems (e.g. one for the residential building and one for the sauna), please complete separate copies of Appendix 2 for each one.
• Attach a site plan as Appendix 1 to the application. The site plan must indicate the locations of buildings, wastewater treatment systems and discharge points, as well as borders and domestic water wells. You can also make a site plan yourself. You can use, for example, the map template of the Espoo Map Service as a basis.
• There are several different grounds for exemption, each with its own appendix. You can use one or more, but only complete the necessary appendices.
  • 3A small volume of wastewater
  • 3B joining the sewerage network
  • 3C high age of the property owner, the property will become uninhabited
  • 3D lack of financial means
• Complete Appendix 4 (exemption from environmental protection regulations) if you only apply for an exemption from the City of Espoo’s environmental protection regulations and the wastewater system of the property already meets the basic-level treatment requirement in accordance with the Environmental Protection Act.
• Send the form and its appendices to the City of Espoo Registry Office at P.O. Box 1, 02070 CITY OF ESPOO or kirjaamo@espoo.fi.

Files: application form, Appendix 2, Appendix 3A, Appendix 3B, Appendix 3C, Appendix 3D, Appendix 4