Flood Detention Reservoirs: A New Wave of Dam Construction in the United Kingdom

Since around 1970 a new wave of dam construction has commenced in the UK, at a rate of around four new reservoirs per year, building flood detention reservoirs (FDR) to reduce flood risk to our urban populations. Although only modest structures, FDRs can pose a significant risk to the community as they are located immediately upstream of the populated areas they are protecting. These communities typically range from around five to several thousand households.
This paper first describes the drivers and context for FDR construction. It then describes some of the technical aspects which differentiate FDRs from other reservoirs The impact of the construction and presence of FDRs on risk assessment is described and how the risk of failure of an FDR is assessed in the UK. It will comment on how increasing use of risk assessment is driving changes in design standards and detailing. Finally, it will conclude with comment on how design, construction and operation of FDRs is likely to change in future years.