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

Rock Lake

Park County, Montana48 acresView map Directions

No nutrient or algae sampling on record from Montana DEQ for this lake.

Area

48 acres

Surface area

Shoreline

1.7 mi

Measured length

See the measurements Directions Where to stay

Rock Lake in Park County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 48 acres.

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Rock Lake is a 48-acre lake in Park County, Montana.

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

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 Montana Department of Environmental Quality 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 Montana DEQ 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

48 acres

Shoreline

1.7 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 Park County, Montana — 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 Park County

Pear Lake1.1 miView →Campfire Lake4.7 miView →Pine Creek Lake—View →Kaufman Lake—View →Dailey Lake—View →Imelda Lake—View →

Frequently asked questions about Rock Lake

Where is Rock Lake?: Rock Lake is a lake in Park County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.
What is the water quality of Rock Lake?: Rock Lake in Park County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 48 acres.
Is Rock Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.