Lake Merwin fishing
Lake Merwin fishing is stocked with Rainbow Trout, Bull trout, Chinook salmon, Coho salmon, Kokanee, Northern pikeminnow, and 1 more on a reservoir. It is stocked about 2 times a year since 2025, most often in July. Species guides list dawn and dusk as the active times.
- Last stocked
- July 13, 2026
- 79 days ago · Rainbow Trout
- Plants on record
- 4
- Since 2025
- Species recorded
- 1
- Average size
- 17.4 in
- Surface acres
- 3,835.6
- Elevation
- 242 ft
Fish at Lake Merwin
Rainbow Trout Stocked · 4 plants · last July 13, 2026 Best: dawn, dusk
Bull trout Confirmed present
Chinook salmon Confirmed present
Coho salmon Confirmed present
Kokanee Confirmed present
Northern pikeminnow Confirmed present
Tiger muskie Confirmed present
How Lake Merwin is stocked
About 2.6 reported fish per acre, the fewest of 5 lakes in Cowlitz County with both a fish count and a surface area.
Fish stocked in 2025
4,965
Fish stocked in 2026
5,111
Stocking history
| Date | Species | Quantity | Avg. length | Source |
|---|---|---|---|---|
| July 13, 2026 | Rainbow Trout | 3,464 | 15.2 in | report |
| July 13, 2026 | Rainbow Trout | 1,647 | 19.5 in | report |
| July 14, 2025 | Rainbow Trout | 3,398 | 15.2 in | report |
| July 14, 2025 | Rainbow Trout | 1,567 | 19.5 in | report |
Access and facts
- Water type
- reservoir
- Shore access
- Yes
- Boat ramp
- Yes
Shoreline access: Good. Very limited.
About Lake Merwin
Nearest lakes
Camping near Lake Merwin
Campgrounds within 15 miles of Lake Merwin's mapped point, nearest first: Cresap Bay Park and Campground (3.1 miles), Cougar Park and Campground (9.2 miles), Merrill Lake Campground (10.1 miles), Beaver Bay Park and Campground (10.3 miles), and Battle Ground Lake State Park camping (12.4 miles), each with its own campground page on campgroundsdb.com.
Straight-line distances.