Great idea! For the hop water, you can start with about 1-2 ounces of fresh Cascade hops per quart of water. Just boil the hops for about 10-15 minutes to extract those great flavors. give it a try and let me know what you think.
1-2oz. per QUART?! That's a LOT of hops.
To report back, I repeated the above process, this time with 4oz. per 5-gal keg, both with leaf hops. (one Cascade, the other Centennial) I also repeated the pH experiment, using the lower pH for the Centennial. It was noticeably crisper. I could have used more hops still. Perhaps using New World varieties with more punch is the better path. (and/or using a 'cool' 165℉ whirlpool)
Honestly, I can't say I prefer one over the other. It's more of a 'what am I in the mood for' sort of difference. (smooth mineral water vs. spritzy 'soft-drink', though both were highly carbed)
Both were well received by festival patrons, though there remains plenty of educational opportunity towards the general public as most have never heard of Hop Water.
I'm still skittish about boiling hops at all for it, as I don't want any IBUs since there are no sugars to balance. I also don't want to risk using yeast because I don't want *any* alcohol produced. (from minute fermentable sugars in hops) That was a selling point at this fest since we were a Designated Driver stop for these beverages. A few folks had heard of Hop Water, but only tried mine because I assured them no yeast was used, and there was no fermentation at all, and it was made fresh that morning.