Mass mortality of fry has been confirmed in Nomi river.

Range that I have confirmed is the carcasses of several thousand animals of fry from near Kamata Station over the National Highway No. 1 on the basin.

This phenomenon has also occurred a few years ago. If the analysis is correct, it is temporarily due to the fact that water quality has become a low-oxygen state in the deposition of sludge by heavy rain. Toxicity of the water quality has not been confirmed.

The difference of the river structure that can be seen as the cause of fry mortality.

The difference in the structure of the basin and the downstream area on the National Highway No. 1. Accumulated sludge in this step will have thought to have fallen into a stretch flows hypoxia in heavy rain.