Its wonderful that your short trip was so productive of hard scientific data, and that your childhood memory was so precise.
You do realise that realise that water tends to leave marks on things, like where tides come up to? You also realise that certain sea-born life forms cling to structures, giving a good indication of usual tidal heights? Do you also realise that engineering of warves and the like hasn't much changed for a long time, ie what was built for a certain size ship last century holds true for the same size ship today? High tide still reaches the same place today as it did when that structure was built. You can see that with one visit at low tide.
As to isostatic rebound, is that what they're using to explain away why we haven't had the tens or hundreds of meters sea level rises we were promised in the 90's? We're in 2015 now. Weren't we all supposed to be drowning by now? Amazing how isostatic rebound so closely matches the exact rate of gw-based sea level rise!
Don't take my word for it. Visit some of these places and have a good look and think for yourself. I know it's hard to do with all that screaming about how only stupid people look at the evidence and make up their own conclusions themselves (with appropriate levels of study involved), and really scary to stand up to the agw bullies for some, but it can be done and you'll soon see how much is truth, and how much really is fear-mongering.
And for the record, I am very much pro cutting pollution, very much pro renewable and nuke (truly green energy if you take the time to look and think), and extremely pro looking after this planet. But that means making the right choices, not the ones some in the gw lobby wants to waste money and resources on.