Headwater 3 : The water immediately upstream from a dam. The water surface elevation varies due to fluctuations in inflow and the amount of water passed through the dam.
Tom Woosley (Program Manager), Georgia Safe Dams Program Inspections and Emergency Action Plans, Glossary, GA Department of Natural Resources, Safe Dams Program, Atlanta, GA, USA 2015. http://www.damsafetyaction.org/GA/other/glossary.p hp, (ND Emr/ Flood - Amer) {909}