Articles | Volume 7, issue 1
Hydrol. Earth Syst. Sci., 7, 75–85, 2003
https://doi.org/10.5194/hess-7-75-2003

Special issue: Understanding hydrological processes in wetlands to improve...

Hydrol. Earth Syst. Sci., 7, 75–85, 2003
https://doi.org/10.5194/hess-7-75-2003

  28 Feb 2003

28 Feb 2003

Hydrological impacts of floodplain restoration: a case study of the River Cherwell, UK

M. C. Acreman1, R. Riddington2, and D. J. Booker1 M. C. Acreman et al.
  • 1Centre for Ecology and Hydrology, Wallingford, OX10 8BB, UK
  • 2Peter Brett Associates,Westcote Road, Reading, RG30 2DE, UK
  • Email for corresponding author: man@ceh.ac.uk

Abstract. This paper investigates the impacts on floods of hypothetical changes to river channel geometry by construction or removal of embankments to prevent water spreading onto the floodplain at high flows. A numerical model is applied to the River Cherwell between Oxford and Banbury to simulate changes to flood hydrographs. Embanking the river increases the peak flows downstream by 50-150%. Restoring the river channel through the floodplain to pre-engineered dimensions reduces peak flow by around 10-15% and increases peak water levels within the floodplain by 0.5-1.6 m. These results suggest that floodplain rehabilitation, in terms of embankment removal or returning the channel to pre-engineered dimensions, can be a valuable part of the flood management strategy of a catchment. Both measures lead to increased inundation of the floodplain, which can be positive for ecological restoration.

Keywords: floodplains, hydrological impacts, rehabilitation, flood frequency