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

Rock Lake

Whitman County, Washington2,190 acresView map Directions

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

Area

2,190 acres

Surface area

Shoreline

18.9 mi

Measured length

See the measurements Directions Where to stay

Rock Lake in Whitman County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Surface area: 2190 acres.

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Rock Lake is a 2,190-acre lake in Whitman County, Washington.

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

What Rock Lake is good for

From access and monitoring records, not editorial picks.

Big water2,190 acres

Swimming conditions

No reading

Not rated

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

Whether Rock 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.

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Water quality measurements for Rock Lake

These are the measurements Washington Ecology publishes for Rock 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 Rock Lake

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

Lake Details

Surface area

2,190 acres

Shoreline

18.9 mi

No bathymetric survey has been published for Rock Lake, so its depth is not documented here.

Stays via Stay22

Stays near Rock Lake

Compare lakeside cabins, hotels, and vacation rentals near Rock Lake in Whitman 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 Rock Lake

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

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Follow Rock Lake’s readings

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Fishing Rock Lake

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

Nearby Lakes in Whitman County

Stevens Lake6.5 miView →Folsom Lake9.9 miView →Crooked Knee Lake11 miView →Sheep Lake—View →

Frequently asked questions about Rock Lake

Where is Rock Lake?: Rock Lake is a lake in Whitman County, Washington. Its water-quality measurements are published by Washington Ecology and shown on this page as reported.
What is the water quality of Rock Lake?: Rock Lake in Whitman County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Surface area: 2190 acres.
Is Rock Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.