The European Working Group on Internal Erosion (EWGIE) was set up in 1993 under the chairmanship of Andrew Charles (Building Research Establishment). 47 case histories were collected and preliminary conclusions drawn as to the features that increase the vulnerability of dams to internal erosion.

Following a number of serious incidents and failures in Europe due to internal erosion, research funding became available, with chairmanship of the EWGIE passing to Jean-Jacques Fry (EDF CIH). An inaugural workshop on definitions and research needs was held at Aussois in April 2005, with subsequent and ongoing annual workshops.

The Interim Report of the European Working group of ICOLD, entitled Assessment of the Risk of Internal Erosion of Water Retaining Structures: Dams, Dikes and Levees, was published at the European Conference on dams in Freising in 2007.

This European Working Group on Internal Erosion is involved in the preparation of the document “Internal erosion of existing dams, dykes and levees, and their foundations”, scheduled for release two volumes in 2012/2013. This Bulletin, being the culmination of interactions which had actually commenced in 1993, is the first ICOLD Bulletin devoted to internal erosion.


Brown A. & Bridle R. (2008), Progress in assessing internal erosion, 15th Conference British Dam Society, University of Warwick, Thomas Telford London 29-38.

Bridle R. & Brown A. (2011), ICOLD bulletin on internal erosion, Dams and Reservoirs, Volume 21, Issue 4, 147 –147.