Bit of a late report here, but we fished the middle section of the Weber River on Sunday, mid-morning to mid-afternoon... pretty slow action overall except for a caddisfly blitz just after 10:00a.
Fish were going crazy, but very localized in activity. The ones I did find were willing risers even though my EH Caddis imitation was a full hook size (#14 to #16) too large compared to the naturals.
I'm pretty sure this fly was the Little Grannom, or Dark Grannom, or Little Western Weedy Water Sedge depending on what you want to call them (Amiocentrus aspilus
for some)... and not the traditional Mother's Day Caddis (Grannom) that many have come to know and love. These smaller variety build those skinny, tapered, cigar-shaped cases (which were everywhere) as opposed to the Brachycentrus'
tapered square cases.
Here's one of the hatched adults that I plucked off the surface (mangling the wings in the process).