Tom, why don't you invest in one of those "camel" bags that cyclists and walkers use - a backpack which is just a water tank, with a tube that comes over your shoulder and is handily placed for putting in your mouth for refreshment!.

Added benefits - you know where it is, you don't have to bend down to pick up the bottle and risk falling off your perch and, with practise, you could probably take a sip during the instrumental riff mid-song!

;-)

I'm only half kidding!

Deirdre