European crayfish was observed in 1989 and Signal crayfish, illegally introduced during the 1990s, is feared to threaten the population of Stone Loach and to bring crayfish plague into the stream.
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Thereafter, the stream flows some 4 km in the valley separating the suburbs Akalla-Hjulsta and Tensta-Rinkeby and where are several rural structures including an ecological farm (Hästa Gård), eight allotment-gardens, and some minor overgrown wetlands.
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While levels of cadmium, copper, zinc, and nickel were reported as increased in ditches draining these deposits, levels of oil, PCB, and chlorinated hydrocarbons were reported as insignificant.
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This part of the catchment area contains a motocross track, a golf driving range, a closed dump, and receives stormwater from the E18 traffic route.