watermarkvalue

This code list is used in association with the Water Mark attribute which is present within the Tidal Boundary Feature Type. The code list describes the state of the tide that the tidal boundary represents (for example, mean high water or normal tidal limit).

Label	Definition
Mean High And Low Water	Coincident occurrence of the average alignment of the high and low tide lines that occurs half way between spring and neap tides.
Mean High And Low Water Springs	Coincident occurrence of the average alignment of the high and low tide lines that occurs when the effects of the sun and moon are in alignment, resulting in a larger than normal tidal range.
Mean High Water	The average alignment of the high tide line that occurs half way between spring and neap tides.
Mean High Water Springs	The average alignment of the high tide line that occurs when the effects of the sun and moon are in alignment, resulting in a larger than normal tidal range.
Mean Low Water	The average alignment of the low tide line that occurs half way between spring and neap tides.
Mean Low Water Springs	The average alignment of the low tide line that occurs when the effects of the sun and moon are in alignment, resulting in a larger than normal tidal range.
Normal Tidal Limit	The highest point in tidal rivers to which mean tides (in Scotland, mean spring tides) flow at high water where there is no other feature present.