Possibly - but mainly that a model four inch head of water just won't make a six inch wide wooden gate seal properly. Magpie spent much of his childhood building model locks in our garden and I don't think any water ever went down the bywash - the lock gates leaked so much! It needed a garden hose to keep the top pound full enough for navigation and the locks, whilst great fun, were more "flash" in operation than would have been desirable in real life.
Doubtless now that both of us have grown up (chronologically if not otherwise!) we could use modern materials, neoprene seals and O Rings together with some decent workmanship to get the thing vaguely watertight.