Waste water

In addition to the scattered waste water regulation, regulations and other issues to be considered when organizing waste water treatment are:

• formula regulations
• Building order of Riihimäki city
• Environmental protection regulations of the city of Riihimäki, which include, among other things, minimum distance requirements for placing the wastewater system and stricter requirements for wastewater treatment in groundwater and coastal areas
• the ground water conditions of the property as well as the quality of the soil and the height relationships give limitations to the use of different systems

Renovating wastewater systems to a level that meets the requirements requires professional planning and construction. Only a qualified designer can make a wastewater system plan. You can apply for qualified water supply planners for scattered settlements from the FISE qualification register. The construction or repair of the wastewater system requires a building control permit or construction permit.

More information: This is how you proceed with the wastewater renovation of a property in a sparsely populated area, article from the Vesi.fi website

A wastewater plan is required for the treatment of wastewater from new properties under construction and old properties that require a building or operation permit. The plan is submitted to building control in connection with the application for a building permit and is a prerequisite for granting the permit. The content requirements of the plan are presented in the scattered waste water regulation. The plan is always drawn up by a competent professional. Wastewater system design in a sparsely populated area, article from the Vesi.fi website

The property must have a report on the waste water system, on the basis of which it is possible to assess the load caused by waste water on the environment. The report must also be drawn up when, pursuant to Section 27 b subsection 2 of the Environmental Protection Act, wastewater can be discharged untreated into the ground. The report must be presented to the supervisory authorities upon request. You can prepare the report yourself and there is no prescribed format, but it must include the following information:

• description of the wastewater treatment system
• assessment of the load on the environment and the fulfillment of the requirements
• station drawing, where the location of the wastewater system and the discharge locations of the wastewater are marked
• information necessary for the use, treatment, maintenance and monitoring of the wastewater system

Compiling the report can be facilitated by, for example, the Finnish Association of Water Protection Associations the form through. On the page, in addition to the report form, you will find the necessary operating and maintenance instruction models and the operating diary.

In the septic tank, floating and settling solids are separated from the waste water. Septic tank treatment does not remove much of the nutrients, and as such is not a sufficiently efficient cleaning system. Precipitation is used in other systems for wastewater pretreatment.

A closed tank is a watertight tank intended for temporary storage of household wastewater or sludge, from which there is no discharge pipe to the environment. The waste water from the tank must be delivered for appropriate treatment.

In Maahaniyättömö, the pre-treated wastewater in the sedimentation well is purified after filtering through the natural soil layers before it is transported to the groundwater. Absorption required favorable soil conditions, and it is not suitable as a treatment option for, for example, important groundwater areas.

In an earth filtration plant, the pre-treated wastewater in the sedimentation pit is purified as it passes through a layer of filter sand built from soil, after which the purified wastewater is collected in a pipeline and further led to the environment or, if necessary, for further treatment.

Small-scale treatment plants are factory-made equipment packages that clean wastewater biologically, chemically or biochemically. Treatment plants often require wastewater pretreatment in septic tanks.

The load caused by waste water on the environment can be reduced by e.g. with a dry toilet, where the waste generated in the toilet is processed by composting. From the point of view of preventing environmental damage, it does not matter whether the load is reduced by making cleaning more efficient or by preventing the creation of wastewater loads, and a dry toilet is an incomparable way to reduce the environmental damage caused by wastewater.

There are four basic options for treating the wastewater of a property inhabited year-round with normal equipment:

• join a centralized drainage system or organize the joint treatment of waste water from several properties, collect all waste water in a closed tank
• build your own soil treatment or small-scale cleaning equipment
• switch to a waterless toilet solution or lead the toilet waste water to a closed tank and the gray waste water to be cleaned for soil treatment, i.e. organize double drainage

In practice, there are several different variations of the systems, and the selection of a suitable system is influenced by e.g. the property's soil quality, elevation and groundwater conditions, and the proximity of water bodies. A professional designer is very important, because this way you get a long-lasting system that fits the conditions of the property, correctly dimensioned and correctly designed and meets the provisions of the regulation.

More information on different processing options, article on the Vesi.fi website

In the scattered waste water regulation, a minimum level of requirements for the cleaning of domestic waste water is defined, as well as an indicative stricter cleaning level. Municipalities can apply stricter cleaning requirements in sensitive areas. In Riihimäki, stricter requirements than the regulation regarding waste water have been issued with environmental protection regulations. In the environmental protection regulations, the requirements of the scattered waste water regulation have been tightened in coastal and groundwater areas. For example, in the groundwater area, it is prohibited to discharge wastewater into the ground or absorb it into the soil. In these areas, all waste water generated on the property must be collected in a tight closed tank, or it must be led in a tight waste water pipe outside the groundwater area.

The cleaning level required in the regulation means an average cleaning result. In practice, the cleaning result can vary from time to time due to, for example, weather conditions or changes in the use of the property, and yet the system meets the requirements of the law. The percentages tell how much of the impurities in untreated wastewater must be removed.

Minimum cleaning level:

• for organic matter (BHK₇) with 80 percent,
• for total phosphorus (P_COOK) with 70 percent and
• for total nitrogen (N_COOK) by 30 percent.

More severe cleaning level:

• for organic matter (BHK₇) with 90 percent,
• for total phosphorus (P_COOK) with 85 percent and
• for total nitrogen (N_COOK) by 40 percent.

Cleaning efficiency is calculated from the daily dirt load of one person's untreated waste water in standard housing. The requirements are defined in the scattered waste water regulation, which also describes the dimensioning of the system in more detail.

The property holder or owner is always responsible for the adequate cleaning of wastewater. If necessary, the property owner must use professional help in order to process the wastewater properly.

The most challenging of the regulation's requirements is phosphorus removal. For example, ordinary ground filters equipped with a settling well are rarely sufficient to clean wastewater in accordance with the requirements of the regulation, and they must therefore be prepared to enhance phosphorus removal.

If water is carried or pumped to the property by hand and the amount of waste water generated is small and does not contain toilet waste water, the waste water can be absorbed into the ground in a controlled manner. However, the measure must not cause a risk of environmental pollution.

The competent authority of the municipality (environmental protection authority in Riihimäki) can, on application, grant permission to deviate from the basic cleaning requirements in the area referred to in § 156 a for a maximum period of five years at a time.

The condition for granting a deviation is that, taking into account the use of the property, the load on the environment must be considered significantly low compared to the load caused by untreated wastewater, or the measures required to improve the treatment system are, due to the high costs and technical demands, considered as a whole unreasonable for the owner of the property. When assessing the unreasonableness of actions 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 who live permanently on the property and other similar special factors related to the life situation;

3) long-term unemployment or illness of the owner of the real estate or other similar social performance impediment.

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

Apply for deviations below electronically license service through.