HIGHWATERMARK
High water mark
A high water mark is a point that represents the maximum rise of a body of water over land. Such a mark is often the result of a flood, although high water marks may reflect an all-time high, an annual high, or the high point for some other division of time. Knowledge of the high water mark for an area is useful in managing the development of that area, particularly in making preparations for flood surges. High water marks from floods have been measured for planning purposes since at least as far back as the civilizations of ancient Egypt. It is a common practice to create a physical marker indicating one or more of the highest water marks for an area, usually ...The above text is a snippet from Wikipedia: High water mark
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