Of course many on this board do not believe it is necessary to treat the Sierra water. However, I am from the school of "an ounce of prevention", and I would gladly pay $100.00 to avoid a case of the "green apple quick step".
I use a Camelback UV filter. Cost is $99.00 at REI, or perhaps less from another online retailer. It takes one minute to treat .75 L. The UV filter will treat many many times on a single charge, and is charged with USB. I had my first unit for only 3 years, when the button started acting "wonky". I called Camelback, and they said send it back. It has a lifetime warranty. I sent it back, they sent me a new one. Gotta love Camelback.
I normally hike with one liter in my backpack, and when that is gone just dip, treat, and drink. If hiking Whitney I follow this procedure until I get to the switch backs, and then I stop and treat two liters (bladder capacity), treat another .75 Liters in my camelback container, and I'm set to go. I also carry a 12 oz gatorade, and either drink it, or fill it with treated water if I have already consumed the contents.
