Rates of overbank sedimentation on the flood plains of several British rivers during the past 100 years

The flood plains of lowland rivers frequently represent important sinks for suspended sediment transported through the river system. However, little is currently known about rates of overbank deposition by British rivers and, more particularly, whether such rates have increased in recent years in response to land use change. The fallout radionuclides Cs and Pb off ;r considerable potential for estimating flood plain sedimentation rates over the past 30-35 years and 100 years respectively. Caesium-137 and Pb measurements have been employed by the authors to investigate sedimentation rates during the past 100 years at five sites on the flood plains of British rivers. At one site a detailed study of the spatial pattern of deposition within a meander bend was undertaken. The results obtained suggest that no significant changes in sedimentation rates have occurred at these sites during the past 100 years. Further work is, however, required to confirm the general applicability of the findings reported.