Easy here's another site with good info on the Yak.
http://www.worleybuggerflyco.com
Make a few trips over before the irrigation season starts. Better to fish from the bank. Look at the river flow charts for info.
Great River to fly fish but I never caught big fish there. Not sure where your located but a lot of the local fly shops have guides that work there. Good luck.
_________________________
God grant me the serenity to accept the size of fish I catch, the courage not to lie about it, and the wisdom to know that no one would believe me anyways.