Equivalent water level
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Definition
Equivalent water level: Low water level, which is reached or fallen below long-term average of 20 ice-free days / year. It is the reference water level for development and maintenance activities of the WSV and for navigation and thus for assessing the fairway conditions.; Equivalent water level [cm at gauge] or [mean sea level + ... cm].; Mutually corresponding water levels of a stream in different outflow cross sections at the same exceeding or undercutting time period.; Water level, resulting from the "equivalent runoff" for a certain condition of the river bed of a stream.