Gunpowder River Hatch Chart
Gunpowder Falls: Located in Baltimore County, Gunpowder Falls is a premier trout fishery. With controlled releases from the Prettyboy Reservoir, the Gunpowder maintains an excellent year-round flow. The Gunpowder is among the few true trout rivers in the DC-MD-VA area offering a variety of water conditions from still water to riffles and rapids. Chest waders are strongly recommended.
| Month | Fly | Size |
| December-January | Woolly Buggers Streamers Midges |
8-10 8-10 18-26 |
| February | Woolly Buggers Streamers Little Black Stoneflies Midges |
8-10 8-10 14-18 20-26 |
| March | Little Black Stoneflies Wooly Buggers Midges |
x14-18 8-10 20-26 |
| April | Hendrickson Red Quill Caddis March Brown Blue Quill |
12-14 12-14 14-20 12-14 14-16 |
| May | Hendrickson Red Quill March Brown Sulphur Blue Winged Olive Light Cahill |
12-14 12-14 12-14 16-20 14-18 14-16 |
| June | Sulphur Light Cahill Blue Winged Olive Caddis Ants/Beetles |
18-20 12-16 20-22 14-20 10-14 |
| July | Sulphur Caddis Ants/Beetles Blue Winged Olive |
20-22 14-20 10-12 20-22 |
| August | Caddis Ants/Beetles Hoppers Blue Winged Olive |
16-20 12-16 10-14 20-22 |
| September | Caddis Nymphs Ants/Beetles Hoppers Woolly Buggers Blue Winged Olive |
16-20 14-18 12-14 8-12 8-10 20-22 |
| October | Caddis Woolly Buggers Streamers Ants/Beetles |
16-20 8-10 8-10 8-12 |
| November-December | Blue Winged Olive Woolly Buggers Streamers |
20-22 8-10 8-10 |