Rock Island Lake
Park County, Montana157 acresView mapDirections
No nutrient or algae sampling on record from Montana DEQ for this lake.
- 110 ft max depth
Rock Island Lake in Park County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Maximum depth: 110 ft. Surface area: 157 acres.
Rock Island Lake is a 157-acre lake in Park County, Montana with a maximum depth of 110 feet.
Source: EPA Water Quality Portal sampling records, Montana DEQ. Methodology: how these readings are compared.
What Rock Island Lake is good for
From access and monitoring records, not editorial picks.
- Camping1 public campground nearby
- Deep water110 ft surveyed max depth
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Rock Island 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.
Water quality measurements for Rock Island Lake
These are the measurements Montana DEQ publishes for Rock Island 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 Island Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
110 ft
Surface area
157 acres
Shoreline
4.2 mi
Recreation & Access
Public campgrounds near Rock Island Lake
- Fox Creek4.7 km
Nearest public campgrounds in the USGS National Map inventory, within about 3 miles. An empty list means USGS records no campground that close, which is not the same as camping being unavailable. Where the source gives an official reservation link, it is used; the cabin and hotel search does not cover campsites. More camping lakes
Stays via Stay22
Stays near Rock Island Lake
Compare lakeside cabins, hotels, and vacation rentals near Rock Island 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 Island Lake
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Fishing Rock Island Lake
Nearby Lakes in Park County
Frequently asked questions about Rock Island Lake
Where is Rock Island Lake?
- Rock Island 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 Island Lake?
- Rock Island Lake in Park County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Maximum depth: 110 ft. Surface area: 157 acres.
Is Rock Island Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Rock Island Lake?
- Rock Island Lake has a maximum depth of 110 feet. The lake covers 157 acres.
Are there campgrounds on Rock Island Lake?
- Rock Island Lake has 1 public campground from USGS The National Map within 5 km, including Fox Creek. This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.
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Where this data comes from
Measurements for Rock Island Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Public campgrounds from USGS The National Map Structures, within about 3 miles