Lake Merwin
Clark County, Washington3,837 acresView mapDirections
No nutrient or algae sampling on record from Washington Ecology for this lake.
- 186 ft max depth
- Public access
Lake Merwin in Clark County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Maximum depth: 186 ft. Surface area: 3837 acres.
Lake Merwin is a 3,837-acre lake in Clark County, Washington with a maximum depth of 186 feet. Limited fish-species data available. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, WA Ecology. Methodology: how these readings are compared.
What Lake Merwin is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Deep water186 ft surveyed max depth
- Big water3,837 acres
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Lake Merwin is safe to swim in today is a call for the Washington State Department of Ecology and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Lake Merwin
These are the measurements Washington Ecology publishes for Lake Merwin, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. TSI undefined.
Ask about Lake Merwin
Answers come straight from the public measurements and survey records on this page.
→ Lake Merwin water level: the live USGS gauge reading
Lake Details
Max depth
186 ft
Surface area
3,837 acres
Shoreline
31.8 mi
Public access
Yes
Listed by Washington Ecology
Recreation & Access
- Speelyai Bay ParkPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Lake Merwin
Compare lakeside cabins, hotels, and vacation rentals near Lake Merwin in Clark County, Washington — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
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Fishing Lake Merwin
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Frequently asked questions about Lake Merwin
Where is Lake Merwin?
- Lake Merwin is a lake in Clark County, Washington. Its water-quality measurements are published by Washington Ecology and shown on this page as reported.
What is the water quality of Lake Merwin?
- Lake Merwin in Clark County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Maximum depth: 186 ft. Surface area: 3837 acres.
Is Lake Merwin safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Lake Merwin?
- Lake Merwin has a maximum depth of 186 feet. The lake covers 3837 acres.
Are there boat ramps on Lake Merwin?
- Lake Merwin has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Speelyai Bay Park. Public access is listed as yes.
Can I fish at Lake Merwin?
- Lake Merwin has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Washington's fish and wildlife agency, so check its current regulations before you go.
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Where this data comes from
Measurements for Lake Merwin come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Named boat-access points from the USGS National Boat Ramps inventory