Adjusting the Transparency of the basic Island Demo water

I have looked through all the questions here concerning adjusting the transparency of the water (any water) in its shader, and so far have come up empty-handed...

The basic "Daytime" water that comes with Unity is totally opaque and has no transparency whatsoever...

One question/answer I saw seemed to indicate that the secret was some setting in the base material... I tried everything with it, including adjusting its alpha layer in Photoshop... No effect...

Another question/answer indicated that I should adjust the horizon color's alpha setting, but the only settings I could alter were those in the color slider bars.... One of them was "A" (which I assumed meant "alpha"), but sliding it didn't seem to affect the transparency of the water at all...

I imported several of the assets from the Island Demo, and was finally able to get the shader working that provided a level of transparency, but it's WAY too clear, and I'd like to make it more opaque... However, once again I can find no setting that indicates I can change the level of transparency, and nothing I've tried seems to work... (I even went into the shader code and tweaked any number that was even nearby anything called "transparency", and nothing changed)...

Am I missing some important step or setting needed to alter the Island Demo's basic, already-existing transparency level? It seems like it would be a simple and basic setting for something like water...

Help would be greatly appreciated...