Air Vent : A pipe designed to provide air to the outlet conduit to reduce turbulence and prevent negative pressures during release of water. Extra air is usually necessary downstream of constrictions
State of Nevada Division of Water Resources (NDWR), Dam Safety - Glossary of Terms, NV, USA 2013. http://water.nv.gov/engineering/Dams/Glossary.cfm, (Dam Sfty - Amer) {891}