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Ecosystem monitoring in large lakes (ØKOSTOR): The program consists of monitoring of large and significant water bodies and boundary waters.

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Project period
The Norwegian Environment Agency
Contact person
Sigrid Haande

About the project

Period: 2015- (ongoing project). Last contract project period: 2021-2025

Read more about the program at The Norwegian Environment Agency

Through the Water Framework Directive (WFD 2000/60/EC), Norway is obliged to manage all water in Norway in an integrated ecological manner, including by monitoring large and significant water bodies and transboundary watercourses. The Norwegian Environment Agency has therefore established a separate monitoring program for 26 large lakes with a focus on determining the ecological status and freshwater ecological development in a selection of the largest Norwegian lakes. Selected lakes are monitored annually to keep track of long-term changes, e.g. in climate. 

Because some of our lakes are special and there are no equivalents in the rest of Europe, separate reference values must be established. The monitoring will strengthen the data basis for establishing reference values for the various quality elements in large lakes. 

The program includes monitoring of water chemistry, phytoplankton, zooplankton, aquatic plants and benthic animals.