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Radioactivity Dynamics in River System


Do sediment with high radioactive cesium concentration continue to be deposited on river bottoms?

Investigations in Fukushima Prefecture have revealed that the concentration of radioactive cesium in river bottoms is generally one or two orders of magnitude lower than in riverbeds*1.

  • Ukedo river(riverbed)
  • Ukedo river(river bottom)

  • Odaka river(riverbed)
  • Odaka river(river bottom)

Fig.1 Concentration of radioactive cesium in surface soil of riverbeds (maximum concentration) and surface sediments of river bottoms at various measuring spots in the Ukedo River and the Odaka River

※ 3~8 samples were taken at each measuring site in riverbeds. The data shown in the figures are the maximum values in these spots.

Reference :*1 “Investigation of Environmental Monitoring Related to Radioactive Materials in Disaster Area of the Great East Japan Earthquake: Region of Public Water ” (Ministry of Environment)