OK, I have this situation, and I am seeking some technical advice:
I have a big army on the Western bank of the Nile river at Memphis. I have a big army inside Memphis, which will be eventually sieged, and which will resist the siege for several years, which include several Nile floodings, harvest, etc... I also have a huge attacking fleet of 200 Greek triereis, plus several native ships of different kinds. I may have, initially, a defending fleet, but it would be eventually destroyed or set to sleep, though all these years.
I need a way for the defenders to keep their control of the Nile, so they can get help and fresh water and food from their Eastern Delta and Upper Egypt allies. Assume the Western bank of the river is taken and the defenders are the only ones in there, everybody else is an attacking force.
I have guessed that the defenders had some support army on the Eastern bank which would be too big a hassle for the attackers to defeat, therefore the Eastern bank is the defenders'.
Now, the questions: which weapon or tactical, or strategical, movements could make the sieged, defenders' army, to keep the attackers away from their food and water supplies, for so many years?
I am guessing some sort of weapon like catapults or "ballistae" that could destroy any attacking fleet on the river before they could make their attack effective. However, my understanding is that most of the war machines that we know, all come from later times... From a National Geographic article: "The origins of the catapult are unknown. They appear in the historical record as early as a 9th-century B.C. relief from Nimrud in modern-day Iraq. Early Greek catapults were large bows that included winches able to draw the weapon for firing." Thus I guess it's safe to assume they, at least, had catapults to defend the harbors...
Please, share your hoplological knowledge, as I can obviously ignore the precise setup and simply say that they couldn't move the huge, all-powerful fleet inside the town because some sort of war machines in the town, but it's an uneasing feeling not being able to know more precisely...
I'd also love a plan map of Memhis, or that White Castle, to be able to understand how they could resist rams and other siege machines for that long. I mean, even Tyre fell! I'm afraid, however, that no such plan maps exist. But any help with descriptions (while I explore Herodotus, and other ancient sources) and reconstructions based on them will be really helpful.
Thanks a bunch!