Cogswell Dam (below)on West Fork San Gabriel River
Conditions right now
No USGS gauge is linked to this water yet, so we can't chart flows.
What's working on West Fork San Gabriel River
- 01Clear skies and mild temperatures create ideal fall conditions.
- 02Primary hatches include Blue-Winged Olives and October Caddis, with consistent midge activity.
- 03Recommended flies: Blue-Winged Olive Comparadun, Travis Hi-Vis BWO Para Emerger, October Caddis (Dry), Zebra Midge, Midge Larva, Olive Woolly Bugger, Schroeder’s Parachute Hopper.
- 04Focus on deeper pools, shaded runs, and areas with structure like undercut banks.
What to tie on at Cogswell Dam (below)
Picked from recent reports for this stretch.
Blue-Winged Olive Comparadun
Matches the anticipated fall Blue-Winged Olive hatches, appealing to selective trout feeding on adults on the surface.
Woolly Bugger (Olive)
This versatile streamer imitates leeches and baitfish, provoking aggressive strikes from larger, predatory trout in the West Fork San Gabriel River as they become more active in cooler fall water.
Travis Hi-Vis BWO Para Emerger
Crucial for targeting trout keying into vulnerable BWO emergers trapped in the surface film during fall hatches.
October Caddis (Dry)
Fall is known for the robust October Caddis hatch, making this a prime pattern for enticing larger trout to the surface in the late afternoon.
Buy at AmazonMidge Larva
Midges are a consistent, year-round food source, becoming particularly important as water temperatures drop in fall, appealing to subsurface feeding trout.
Buy at AmazonZebra Midge
A highly effective subsurface pattern for imitating abundant midge pupae, which are a staple diet for trout in the cooler fall conditions.
Buy at AmazonSchroeder Rouse’s J-Dub Sow Bug
On warmer fall days, terrestrials like grasshoppers can still be dislodged from streamside vegetation, providing a substantial meal for opportunistic trout.
Micro Egg
Egg patterns are effective in the fall, mimicking eggs from spawning fish, which can be a calorie-rich food source for trout.
Buy at AmazonCalifornia season by season
What changes on the water through the year, with the flies for each season.
Fly shops nearby
Local flies, current advice and guided trips.