Ephemeral drainage definition
Ephemeral drainage means a stream or reach of a stream that flows only in direct response to precipitation or to the melting of snow or ice in the immediate watershed.
Ephemeral drainage for purposes of this LAMP, means a stream, or other drainage such as a roadside ditch, that flows for less than five days after the passage of a storm. An ephemeral stream only carries water in direct response to a precipitation event and it contains no water from a spring, snow, or other long-continuing surface source. Setback measurements are made from the edge of the channel.