Mean high water line/mark (MHWL)

The line on the shore in tidal areas established by the fluctuations of water and indicated by physical characteristics such as a clear, natural line impressed on the bank, shelving, changes in the character of soil, destruction of terrestrial vegetation, the presence of litter and debris, or other appropriate means that consider the characteristics of the surrounding area. (US Army Corps of Engineers New York District, Regulatory Program Applicant Information Guide, 2014)