Crest Width (Top thickness) : The thickness or width of a dam at the level of the crest (top) of the dam. The term "thickness" is used for gravity and arch dams and "width" for other types of dams
National Weather Service NWS Forecast Office, National Oceanic and Atmospheric Administration NOAA, SH Manual, Glossary of Hydrologic Terms, Washington, DC, USA 2015. http://www.nws.noaa.gov/om/hod/SHManual/SHMan014_g lossary.htm, (HydroI - Amer) {889}