Top Thickness (Top Width) : The thickness or width of a dam at the level of the top of dam (excluding corbels or parapets). In general, the term thickness is used for gravity and arch dams, and width is used for other dams
National Dam Safety Program, U.S. Department of Homeland Security Federal Emergency Management Agency Interagency Committee on Dam Safety, Federal Guidelines For Dam Safety: Glossary of Terms For Dam Safety (FEMA-148), Washington DC, USA 2004. http://www.damsafety.org/media/Documents/PDF/fema- 148.pdf, (Dam Sfty - Amer) {890}