# 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         | <p>Coincident occurrence of the average alignment of the high and low tide lines that occurs half way between spring and neap tides. <br>Represented in England and Wales only.</p>                                                     |
| Mean High And Low Water Springs | <p>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.<br>Represented in Scotland only.</p> |
| Mean High Water                 | <p>The average alignment of the high tide line that occurs half way between spring and neap tides.<br>Represented in England and Wales only.</p>                                                                                        |
| Mean High Water Springs         | <p>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.<br>Represented in Scotland only.</p>                                   |
| Mean Low Water                  | <p>The average alignment of the low tide line that occurs half way between spring and neap tides.<br>Represented in England and Wales only.</p>                                                                                         |
| Mean Low Water Springs          | <p>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.<br>Represented in Scotland only.</p>                                    |
| 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.                                                                                      |


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