Mean Lower Low Water
The United States' National Oceanic and Atmospheric Administration uses mean lower low water (MLLW), which is the average height of the lowest tide recorded at a tide station each day during the recording period. MLLW is only a mean, so some tidal levels may be negative relative to MLLW.
Read more about this topic: Chart Datum
Famous quotes containing the word water:
“I hear lake water lapping with low sounds by the shore;
While I stand on the roadway, or on the pavements gray,
I hear it in the deep heart’s core.”
—William Butler Yeats (1865–1939)