The mean concentration of heavy metals show that the water and fishes of Langtang-North big and small dams are free of industrial pollutions. This is evident in the absence of industrial activities in Langtang-North. A clear representation of the level of heavy metals in figures 1.1 and 1.2 shows that higher levels of Cadmium, Iron and Manganese are present in the big dam than the smaller dam and the amount of these metals are more present in the fish samples than the water samples. This is similar to the findings of .