Where is Castle Lake?

Castle Lake is a lake in Cowlitz County, Washington. Its water-quality measurements are published by Washington Ecology and shown on this page as reported.

How deep is Castle Lake?

Castle Lake has a maximum depth of 97.7 feet and an average depth of 62 feet. The lake covers 279 acres.

Castle Lake

Cowlitz County, Washington279 acresView map Directions

No nutrient or algae sampling on record from Washington Ecology for this lake.

Max depth

97.7 ft

Bathymetric survey

Area

279 acres

Surface area

Shoreline

3.9 mi

Measured length

98 ft max depth

See the measurements Directions Where to stay

Castle Lake in Cowlitz County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Maximum depth: 97.7 ft. Surface area: 279 acres.

Loading map…

Castle Lake is a 279-acre lake in Cowlitz County, Washington with a maximum depth of 98 feet (62-foot average).

Source: EPA Water Quality Portal sampling records, WA Ecology. Methodology: how these readings are compared.

What Castle Lake is good for

From access and monitoring records, not editorial picks.

Deep water97.7 ft surveyed max depth

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.

Whether Castle Lake 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.

Get alerts for Castle Lake →

Water quality measurements for Castle Lake

These are the measurements Washington Ecology publishes for Castle Lake, 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 Castle Lake

Answers come straight from the public measurements and survey records on this page.

→ Castle Lake water level: the live USGS gauge reading

Lake Details

Max depth

97.7 ft

Average depth

62 ft

Surface area

279 acres

Shoreline

3.9 mi

Stays via Stay22

Stays near Castle Lake

Compare lakeside cabins, hotels, and vacation rentals near Castle Lake in Cowlitz 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.

Top-rated places to stay near Castle Lake

Prices for Oct 16–18, 4 adults. Change dates on the map below.

Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.

Planning a whole trip? See where to stay at Washington’s top lakes →

Follow Castle Lake’s readings

Email me when new measurements post for this lake. Updates stay free.

Or email

Fishing Castle Lake

→ Castle Lake fishing regulations (limits, seasons, special rules)

Nearby Lakes in Cowlitz County

Merrill Lake11.2 miView →Swift Number Two Forebay13.2 miView →Silver Lake—View →Log Pond—View →Lake Sacajawea—View →

Frequently asked questions about Castle Lake

Where is Castle Lake?: Castle Lake is a lake in Cowlitz County, Washington. Its water-quality measurements are published by Washington Ecology and shown on this page as reported.
What is the water quality of Castle Lake?: Castle Lake in Cowlitz County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Maximum depth: 97.7 ft. Surface area: 279 acres.
Is Castle Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Castle Lake?: Castle Lake has a maximum depth of 97.7 feet and an average depth of 62 feet. The lake covers 279 acres.