Hey BADFISH, don’t ever let anyone tell you it’s tough to catch wallies on flies. Sometimes it’s the best way to fish them. Other times it is only a novelty and you will do better with spinning gear.
Utah Lake and Willard are the two best spots for waving a fairy wand for walleye. If you use weighted streamers or buggers, you can often get by with a full floating line in shallow areas. In deeper water, and with unweighted offerings, you should use a sink tip. To do the “tubing troll”, a full sinking line, in deeper water, can be very effective also.
Your color selections are good. I would only suggest two additional colors: white and yellow. Add some silver sparkle goodies to the white, and finish it with a hot red head. Add gold sparkle to the yellow and finish it with a dark red head…although hot red is good too. A red head is also good for the black and purple.
I used to do best consistently with large black wooly buggers. They resemble the small mudcats that big predators dine on. You will also take both channels and largies on the black…as well as some overconfident whities.
The white and silver obviously represents the small white bass in the lake…another favorite snack food. Of course, they also eat small crappies or other silvery/white fish too. Yellow and gold can represent junior carp or sunfish…or yellow perch. A wisp of bright orange or even red can help the visibility and contrast.
If you fish the rocky areas around Utah Lake, be sure to tie your big offerings with mono weed guards. They can save a lot of flies and the potential for spooking fish in the shallow water while you try to extricate your flies.
On Willard, you can either move along the dikes, casting parallel to the rocks…or you can lay out a short cast, allow the fly to sink a ways and then kick along in your float tube…giving the fly a little “shivver” once in awhile.
When the small males are active, during spawning season, you can get some “pop on the drop” hits. If you lay the fly in the middle of some activity, it will often get munched as it sinks through the feisty little fellers. Watch your line for a twitch, just like if you were nymphing for trout.
Otherwise, you need to try a variety of retrieves. I usually like to fish the fly like I fish a popper for bass. Let it sink to the bottom and then don’t move it for a few seconds. Then you either strip it slowly, to keep it down, or give it a “shivver lift”…starting with your rod low and then slowly raising the tip while giving it a little wiggle. Make it look like a distressed minnow or crawdad rising up off the bottom. That is a very effective technique for a lot of species, and often generates a reaction bite in neutral or inactive fish. Of course walleye are never in those modes. HA.
Another thing to try is a tandem fly rig. Use a large offering on the end, with a smaller and different color about 18" to 24" inches up the leader…on a 6" dropper. Sometimes you score on one and not the other…with different species. Other times, one fly will catch all the fish, but you need the second fly to create the multiple target illusion.
One mistake a lot of guys make is working too much line. If you are quiet…wading or tubing…you do not need to make long casts. A thirty foot controlled cast is much better than a sixty foot splashdown. These fish are not finicky browns in crystal clear water, but they are very sensitive to noise and vibrations. If you are going to use a flyrod, be sure you use it right.
And, working closer will give you greater feel for the sometimes gentle takes on a fly. Often, the “strike” will be nothing more than a brief “rubber band” feel. Walleye can really slam a noisy crankbait, out of anger or whatever, but they usually just flare their gills and suck in a fly…or simply open and close their mouths to sample it. If you are not “tuned in”, you will miss some of those all too rare opportunities.
I only caught one walleye from Deer Creek on a fly. I got it on a 3" long perch pattern streamer, right on the rocks, right at daybreak late in the summer. I had been fishing for some of the large browns and bass that were chasing the young-of-the-year perchlets. The walleye rolled on the fly almost as soon as it touched down. Man, was I (pleasantly) surprised. But, wouldn’t you know it, I couldn’t score another one no matter how hard I tried and no matter how many different flies and lures I tried.
Oh yeah, I have taken some other walleyes by trolling flies with spinning gear and a piece of lead core. That’s a good technique in Deer Creek for big trout, bass…and walleyes. But, that’s another post.
PM me if you wanna trade some patterns. I am including a couple of attachments. One is of some of the flies I put together for fishing that area. Not all of my suggestions are included. But, note the blue back and red back whites. That is a good pattern. I am also including a diagram for two ways to tie in mono weed guards.