| Valkjärvi | |
| Location: | Nurmijärvi, Uusimaa |
| Coords: | 60.4025°N 24.72°W |
| Pushpin Map: | Finland |
| Outflow: | Luhtajoki |
| Basin Countries: | Finland |
| Cities: | Klaukkala |
Valkjärvi is a lake located in the Nurmijärvi municipality in Southern Finland. It is an island-free lake in the immediate vicinity of Klaukkala's urban area. The water flows from the lake along the Luhtajoki River all the way to the Vantaa River.[1]
Valkjärvi is the most lushest lake of Nurmijärvi,[2] [3] and it is part of the Nurmijärvi's lake monitoring program of the Central Uusimaa Environment Centre (Keski-Uudenmaan ympäristökeskus) due to its poor oxygen values near the bottom of the lake, which are observed especially in summer and winter under ice.[4] [5] Blue-green algae are quite common in the lake; in July 2015, the phytoplankton in the lake with the highest total biomass consisted of 40% cyanobacteria and 29% cryptomonad.[2]
Despite all this, Valkjärvi has great recreational value and there are quite a lot of both permanent and holiday settlements around the lake.[5] There are two beaches at the southern end of Valkjärvi: Tiiranranta Beach and Lähtelä Beach.[6]