The state of Finland’s surface waters

	© Marja Pylvänäinen

The state of Finland’s lakes, rivers and marine waters is continuously monitored through the environmental administration’s monitoring scheme, and through compulsory inspections funded by industrial operators and other businesses obliged to monitor their own impacts.

Administrative monitoring and compulsory inspections together cover thousands of observation points around the country. The frequency of water quality observations and the factors under analysis vary according to local needs. Biological monitoring has been increased, and will continue to be expanded over the coming years. The most important biological monitoring indicators are phytoplankton, benthic fauna, diatoms, aquatic plants and fish. Fish monitoring is conducted by the Finnish Game and Fisheries Research Institute and the regional employment and economic development centres.

Results from the environmental administration’s monitoring and compulsory inspections are logged in the national HERTTA database, which is run by the Finnish Environment Institute (SYKE). This extensive database contains information dating back to the 1960s, and now also has a related internet service known as OIVA.

Monitoring data is very widely used, for instance to classify the ecological states of specific rivers, lakes and coastal waters. The first comprehensive classification was published in June 2008. The classification system particularly focuses on biological water quality factors. In each surface water body (rivers, lakes, coastal waters in their entirety or parts thereof) the states of communities of planktonic algae, diatoms, aquatic plants, benthic animals and fish are compared to conditions that would prevail if the water body were unaffected by human activity. Ecological water quality is highest where human impacts are least significant. In addition to biological factors, evaluations also consider physical and chemical parameters that affect water quality.

In previous years surface water bodies were classified according to their overall usability with an emphasis on human needs. Usability classifications have been based on water quality factors, but also considered other factors such as the presence of algal blooms.