Radioactivity Dynamics in River System
（2014）
ＱDoes the concentration of radioactive cesium increase due to the resuspension of sediments by heavy rains?
ＡInvestigations at the Ogaki dam in Fukushima Prefecture have revealed that the flow rate downstream of the dam is low even during periods of high reservoir water levels. Therefore, it appears that it is difficult for reservoir bed sediments to be resuspended. The turbidity at the surface of the lake is due to sediment inflow from upstream.
Fig.1 Vertical distribution of flow rate from upstream to downstream (downstream of silt fence) of Ogaki dam lake at high water-level time
Fig.2 Map is cited from Map data by Geographical Survey Institute
Fig.3 Vertical distribution of turbidity and temperature of water from upstream to downstream of Ogaki dam lake during a high water level period
In the upstream region, flow rates at the reservoir bottom were around 10 cm/s at high water-level time. In this period, turbid water moved to middle and lower layers. In the downstream (downstream of fence), on the other hand, apparent change of flow rate was not observed even at the time of water discharge.
Related articles
- Will radioactive contamination continue to accumulate in reservoirs due to the inflow of radioactive cesium from rivers? 【Tendency of the change of the concentration in reservoir beds】
- Will radioactive contamination continue to accumulate in reservoirs due to the inflow of radioactive cesium from rivers? 【Effect of the upstream dam on 137Cs accumulation in the riservoir beds】
- Does radioactive cesium move from the ground surface to underground or into groundwater? 【Movement in underground water】
- Does radioactive cesium move from the ground surface to underground or into groundwater? 【Vertical movement in soil】
- Does the concentration in river water change before and after forest fire? How did it change by time?