Summary of the International Commission on Large Dams (ICOLD) bulletin on internal erosion of existing dams, levees and dikes and their foundations
Internal erosion is a major cause of embankment failure, albeit that such failure is quite rare. In the UK incidents involving internal erosion are usually well managed but awareness of the issues involved is important. When constructing new dams, protection against internal erosion is provided by zoning and by providing filters, however many existing dams are not adequately zoned and do not have filters and may therefore be vulnerable to internal erosion. Others have filters not designed and/or constructed to modern standards and they too may be vulnerable to internal erosion.