I live on a sailboat in the Treasure Coast of Florida (for now anyway). WE are at sea level in the Indian River, a river that is tidal, though not much of a tide here. It varies about 1ft from low to high most days. So, we either have to step onto the boat from the fixed dock, or, step down. When the winds blow hard off the ocean, we might have to step up. The docks have been here and haven’t changed in 20+ years (we’ve only been here a few years), but, nothing has changed around here.
It does vary a little, but, not by much.
the only time that actually changes, is when the tectonic plates of a coastal region start sublimation... or so I am told. The sea stays the same tidal circadian solar/lunar cycles... while moving the tectonic plates up or down a few feet may adjust WHERE on he new lower or elevated shoreline the tidelines fall...
does that make any sense.