The microbiological quality of swimming waters in Central Uusimaa is good
On 4 June 2026, the Central Uusimaa Environment Centre took the first water quality samples of the summer from the beaches in Järvenpää, Mäntsälä, Nurmijärvi and Tuusula in accordance with the monitoring plan. The samples were tested for Escherichia coli bacteria and faecal enterococci. The microbiological quality of the swimming water met the quality requirements set for bathing water.
No blue-green algae were observed on the beaches at the time of sampling. However, you should always check the situation yourself before going for a swim, as conditions can change rapidly.
Blue-green algae proliferate as the water warms up. In windy weather, blue-green algae may be suspended in the water, whereas in calm, sunny weather they rise to the surface.
Water samples were taken from the following lakes and beaches:
- Järvenpää: Tervanokka Beach (Lake Tuusula)
- Mäntsälä: Mäntsälä Municipal Beach (Lake Keravanjärvi) and Saari Beach (Lake Hunttijärvi)
- Nurmijärvi: Sääksjärvi beach and Valkjärvi beach
- Tuusula: The ponds at Häklin and Urheilupuisto, and the Rusutjärvi
At the time of sampling, the water temperatures at the bathing beaches ranged from 14.5 to 20.8 °C. The warmest swimming water was at Tervanokka beach in Järvenpää, whilst the coolest was at Saari beach in Mäntsälä.
Providing information on bathing water quality
The Central Uusimaa Environment Centre’s website features a table where the results of water samples taken during the swimming season are updated.
The test results are also displayed on noticeboards at the beaches.
Blue-green algae sightings can be tracked on the Järvi-meriwiki website, maintained by the Finnish Environment Institute, where anyone can also report their own sightings.
Further information:
Pia Gummerus, Health Inspector, tel. 040 314 4722, email pia.gummerus@tuusula.fi
Helmi Heiska, Health Inspector, tel. 040 314 4745, email helmi.heiska@tuusula.fi
This content has been translated using AI