There is no magic formula to float tanks full of water, at any such high capacity, is my point.
That 66 MILLION gallons of water has mass. To SUPPORT that mass, you need a physical structure. To FLOAT it, it has to be MUCH more massive.
You're talking about creating this as if it's child's play. Reality does not support your position, any more than Ellmer' and Matius' V shaped boomerang 'city'. The stresses may not even be calculable, when you throw a storm at it.
I am NOT saying there is no way, but storing that much water, as a physical battery, of 2hrs 45min capacity, for a floating city is physically impossible, without Star Trek miracles that real science doesn't support.
A nuclear reactor is far more realistic. There are dozens, if not hundreds of them, already at work, for far less, in the worlds oceans, thanks to the Navies of the US, Russia and China.
I've already outlined a way to create a non-floating breakwater that the science, economics, and physical capability IS available for. Even the theory for making such a structure was fantasy, 20 years ago.
There are cheaper, more effective ways to do it. Since ot depends on modulating the energy in the waves, to 'charge' a layer beneath the surface, take it the next step and add underwater turbines, instead. STILL too expensive to get, and maintain those underwater turbines, to currently justify, but far more feasible.