Lake Merwin Fishing
A 3,836-acre Washington lake in Clark and Cowlitz counties.
Pick for troutPiscifun Carbon X ultralight spinning reel28% OFFSale $57.99 Photo: Sam Beebe, CC BY 2.0
First look at Lake Merwin
By the WDFW lake layer, Lake Merwin covers 3,836 acres of Clark and Cowlitz counties. Expect an elevation of about 242 feet at the shoreline. Amboy lies near 5 miles from the WDFW lake point. WDFW treats it as mixed-species water managed with a trout emphasis. It falls within WDFW Region 5 by the plant report.
No ramp shows up on it in the layers we use. The shore fishing layer adds 3 shore fishing sites. Read 2 Special Rules before keeping a fish. The trout plant report counts 2 trout plants for 2026. The access field reads good.
WDFW Fish Washington lake layers on geodataservices.wdfw.wa.gov (surface acres, elevation, management emphasis, shoreline access, species), USGS NHD outlines, Census 2023 places, retrieved October 31, 2026.
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Fish on file for Lake Merwin across the WDFW layers and plant report:
WDFW Fish Washington species layers (presence, not abundance), WDFW records and the 2026 trout plant report; retrieved October 31, 2026.
Launching on Lake Merwin
The WDFW and State Parks layers list no launch on Lake Merwin; the closest listed ones follow.
WDFW piers and shoreline sites on Lake Merwin
- Merwin Reservoir shore accessshore fishing site, 600 feet of shore fishing, includes a swim area during summe
- Merwin Reservoir shore access near Amboyshore fishing site, 300 feet of shore fishing north and south of the boat ramp
- Merwin Reservoir fishing piershore fishing site, Shore fishing east and west of boat ramp, includes a swim ar
Concrete and gravel ramps by Lake Merwin
- Cedar Creek boat launchCedar Creek, 9 miles west
- Island boat launch on Lewis RiverLewis River, 12 miles west
- Battle Ground Lake boat launchBattle Ground Lake, 12 miles south
WDFW Water Access Sites and Shore Fishing Sites layers (geodataservices.wdfw.wa.gov) and the Washington State Parks boat launch layer, retrieved October 31, 2026. A Discover Pass is needed to park at WDFW access sites and State Parks launches.
Where the surface sits on Lake Merwin
| USGS gauge | Latest reading | Time (ET) |
|---|---|---|
| Lake Merwin Near Chelatchie, Wa | 225.00 ft lake elevation | Nov 1 7:00 pm |
US Geological Survey provisional data, retrieved Nov 1, 2026 6:33 pm ET. Provisional readings can be revised.
USGS lake gauges update live; Corps forebay figures are the dated reading we retrieved.
WDFW releases into Lake Merwin
Plants logged for Lake Merwin this year: 2 rows, 5,111 fish.
- Lake MERWINRainbow, 1,647 fish at 0.3 per pound, July 13, 2026, Merwin Hatchery
- Lake MERWINRainbow, 3,464 fish at 0.7 per pound, July 13, 2026, Merwin Hatchery
WDFW Trout Plants report (rows January 2 to October 27, 2026), read October 31, 2026.
Daily limits, Lake Merwin
| Species | Daily limit and size | Season |
|---|---|---|
| Largemouth Bass | No min. size in lakes, ponds, and reservoirs. Only largemouth bass less than 12" may be retained, except 1 over 17" may be retained. Daily limit 5. | Lakes, ponds, and reservoirs: year-round; rivers, streams and beaver ponds: Sat. before Memorial Day through Oct. 31 |
| Smallmouth Bass | No min. size in lakes, ponds, and reservoirs. Only 1 smallmouth bass over 14" may be retained. Daily limit 10. | Lakes, ponds, and reservoirs: year-round; rivers, streams and beaver ponds: Sat. before Memorial Day through Oct. 31 |
| Walleye | Min. size 12" in lakes, ponds, and reservoirs. Daily limit 8. Only 1 over 22" may be retained. May be caught, retained, and released alive from a livewell until daily limit is in possession. | Lakes, ponds, and reservoirs: year-round; rivers, streams and beaver ponds: Sat. before Memorial Day through Oct. 31 |
| Channel Catfish | No min. size in lakes, ponds, and reservoirs. Daily limit 5. | Lakes, ponds, and reservoirs: year-round; rivers, streams and beaver ponds: Sat. before Memorial Day through Oct. 31 |
| Burbot (Freshwater Ling) | No min. size. Daily limit 5. | Lakes, ponds, and reservoirs: year-round; rivers, streams and beaver ponds: Sat. before Memorial Day through Oct. 31 (p.23 general rule for |
| Crappie, Northern Pikeminnow, Peamouth Chub, Perch, Suckers, Sunfish, | No min. size. No daily limit. | Lakes, ponds, and reservoirs: year-round; rivers, streams and beaver ponds: Sat. before Memorial Day through Oct. 31 |
| Grass Carp | Closed unless otherwise listed in Special Rules. | Closed |
| Kokanee | No min. size. Daily limit 10. When fishing with bait, all kokanee that are lawful to possess and are equal to or greater than the minimum size are counted as part of the daily limit whether kept or released. | Lakes, ponds, and reservoirs: year-round; rivers, streams and beaver ponds: Sat. before Memorial Day through Oct. 31 (p.23 general rule for |
| Tiger Muskellunge (Tiger Muskie) | Min. size 50". Daily limit 1. | Lakes, ponds, and reservoirs: year-round; rivers, streams and beaver ponds: Sat. before Memorial Day through Oct. 31 (p.23 general rule for |
| Whitefish | No min. size. Daily limit 15. | Lakes, ponds, and reservoirs: year-round; rivers, streams and beaver ponds: Sat. before Memorial Day through Oct. 31 (p.23 general rule for |
| Steelhead | Release all wild steelhead. Min. size 20". Daily limit 2. Open during salmon or game fish seasons unless as otherwise listed. | Open during salmon or game fish seasons unless as otherwise listed |
| Brown Trout, Cutthroat Trout, Rainbow Trout, Golden Trout, Tiger Trout | In lakes, ponds, and reservoirs: No min. size. Daily limit 5. | Year-round (statewide lake season, p.23) |
| Trout (combined rivers and lakes same day) | The combined daily limit for an angler that fishes in both rivers and lakes on the same day is 5 trout, no more than 2 may be from rivers. | see the pamphlet |
| Lake Trout | No min. size. No daily limit. | Lakes, ponds, and reservoirs: year-round; rivers, streams and beaver ponds: Sat. before Memorial Day through Oct. 31 (p.23 general rule for |
| Eastern Brook Trout (EBT) | No min. size. No daily limit. | Lakes, ponds, and reservoirs: year-round; rivers, streams and beaver ponds: Sat. before Memorial Day through Oct. 31 (p.23 general rule for |
| Dolly Varden/Bull Trout | Closed unless otherwise listed in Special Rules. | Closed |
The statewide freshwater limits are the default at Lake Merwin, with Special Rules on top.
How Lake Merwin breaks with the statewide tables
| Water as printed | Species | Rule and season |
|---|---|---|
| Merwin Lake | All game fish | Statewide min. size/daily limit. (Year-round) |
| Merwin Lake | Salmon | Landlocked salmon rules. (Year-round) |
Special Rules as printed in the 2026-2027 Washington Sport Fishing Rules (WDFW pamphlet, in effect July 1, 2026 to June 30, 2027), pamphlet page 86 (pamphlet PDF), read on eRegulations October 31, 2026.
Anglers 16 and older need a Washington Freshwater license ($39.95 resident, $115.85 nonresident for 2026-27) or a Combination license; salmon, steelhead and sturgeon also take a catch record card.
Limits and seasons as printed in the 2026-2027 Washington Sport Fishing Rules (WDFW pamphlet, in effect July 1, 2026 to June 30, 2027), PDF page 27 (pamphlet PDF; eRegulations statewide freshwater page), read October 31, 2026.
Lake Merwin beside nearby lakes
Yale Reservoir is the biggest of these neighbours, 3,612 acres by WDFW.
| Lake | Distance | Acres | Elevation | Launches | 2026 plants |
|---|---|---|---|---|---|
| Lake Merwin | 3,836 | 242 ft | 0 | 2 | |
| Yale Reservoir | 6 miles east | 3,612 | 486 ft | 0 | 0 |
| Fargher Lake | 7 miles southwest | 16 | 664 ft | 0 | 0 |
| Merrill Lake | 10 miles northeast | 283 | 1,524 ft | 0 | 0 |
| Swift Power Canal | 12 miles northeast | 91 | 607 ft | 0 | 4 |
| Battle Ground Lake | 12 miles south | 25 | 509 ft | 2 | 14 |
WDFW Fish Washington lake layers, access layers and the 2026 trout plant report; retrieved October 31, 2026.
Not far from Lake Merwin
More Washington lakes around Lake Merwin
- Yale Reservoir6 miles east
- Fargher Lake7 miles southwest
- Merrill Lake10 miles northeast
- Swift Power Canal12 miles northeast
- Battle Ground Lake12 miles south
Shops to stop at before Lake Merwin
- Sportsman's Warehouse Vancouversporting goods store, Vancouver, 22 miles
- Sportsman's Warehouse Kelsosporting goods store, Kelso, 24 miles
- Cannon Marinemarina, Brush Prairie
- Pacific Northwest Sporting Goodbait and tackle shop, Camas
- Marina Ridgefieldmarina, Ridgefield
- Felida Moorage & Marine Servicemarina, Vancouver
Hiring a guide on Lake Merwin
- Fish Hunters Guide Servicecharter, Washougal, (360) 910-4542
- Fishing With Larry Schoenborncharter, Vancouver, (360) 260-7138
- Columbia River Fishing Slayerfishing guide, Castle Rock, (360) 270-0641
Cities and towns within reach of Lake Merwin
- Amboy5 miles
- Yacolt8 miles
- Lewisville12 miles
County pages covering Lake Merwin
- Clark Countyseat: Vancouver
- Cowlitz Countyseat: Kelso
Piscifun tackle sorted for the drive to Lake Merwin
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Photographs of fishing water around Lake Merwin
Photo: David Burn, CC BY-SA 2.0
Photo: PNWDawn, Public domain
Photo: Cory Barnes, CC BY-SA 2.0
Photo: Jeff Hollett, CC0 1.0
Clearing up a trip to Lake Merwin
Which county line is Lake Merwin near?
Its WDFW point falls inside Clark and Cowlitz counties, about 5 miles from Amboy.
How many surface acres does WDFW list for Lake Merwin?
Roughly 3,836 acres.
Where does a trailered boat go in at Lake Merwin?
No listed ramp; use a nearby one or carry in a small craft.
Which species swim in Lake Merwin?
WDFW points to kokanee, tiger muskie and rainbow trout.
Does a minimum or slot size apply to fish kept at Lake Merwin?
Brown Trout, Cutthroat Trout, Rainbow Trout, Golden Trout, Tiger Trout: In lakes, ponds, and reservoirs: No min. size. Daily limit 5.; Year-round (statewide lake season, p.23). A Special Rule changes part of that here, as shown above.
Is a catch record card needed on Lake Merwin?
Anglers 16 and older need a Washington Freshwater license ($39.95 resident, $115.85 nonresident for 2026-27) or a Combination license; salmon, steelhead and sturgeon also take a catch record card.
How many trout has WDFW put in Lake Merwin?
The report lists 2 plants, latest Rainbow, 1,647 fish at 0.3 per pound, July 13, 2026, Merwin Hatchery.
Which Washington tackle counter on our list is handy to Lake Merwin?
Closest on our list: Sportsman's Warehouse Vancouver, about 22 miles away.
How full is Lake Merwin by the latest reading?
The level band draws on USGS.
Put Lake Merwin on the list before the next plant
Buy the WDFW license online before leaving town.