The elevation in feet above sea level, which approximates the level of flooding expected on a frequency of not less than the ten (10) year recurring interval, or on a frequency of not greater than a ten percent (10%) probability of occurrence in any given year, as determined from analysis of best available data.
TEN (10) YEAR FLOOD WARNING LEVEL
Meaning of TEN (10) YEAR FLOOD WARNING LEVEL in English
Environmental engineering English vocabulary. Английский словарь экологического инжиниринга. 2012