Rainy Lake Deep
Missoula County, MontanaView mapDirections
Montana DEQ publishes the water-quality measurements for Rainy Lake Deep. Here is what has been measured.
- Limited data
Rainy Lake Deep in Missoula County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Water clarity: 18.9 ft visibility.
Rainy Lake Deep is a lake in Missoula County, Montana. Overall water quality is improving over recent sampling years.
Source: EPA Water Quality Portal sampling records, Montana DEQ, last sampled 2019-09-04. Methodology: how these readings are compared.
For a place on the water, look through cabin and lake-house rentals near Rainy Lake Deep on Vrbo. For a hotel or motel room, Booking.com and Expedia both search around the lake.
What Rainy Lake Deep is good for
From access and monitoring records, not editorial picks.
- Clear water18.9 ft of visibility
- Camping1 public campground nearby
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Rainy Lake Deep 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 Rainy Lake Deep
These are the measurements Montana DEQ publishes for Rainy Lake Deep, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Crystal clear, you can see 18.9 ft down. TSI 35.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 18.9ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | No reading The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. | |
| Chlorophyll-a (algae) | No reading The green pigment in algae — a direct measure of how much algae is in the water. | |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 35 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Rainy Lake Deep
Answers come straight from the public measurements and survey records on this page.
Lake Size & Watershed
Watershed (drainage) area
30 sq mi
HydroLAKES / HydroSHEDS
Surface area
79 acres
HydroLAKES / HydroSHEDS
Shoreline
1.4 mi
HydroLAKES / HydroSHEDS
Elevation
4,101 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
Public campgrounds near Rainy Lake Deep
- Rainy Lake Campground0.3 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 Rainy Lake Deep
Compare lakeside cabins, hotels, and vacation rentals near Rainy Lake Deep in Missoula 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 Rainy Lake Deep
Prices for Oct 30–Nov 1, 4 adults. Change dates on the map below.
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Fishing Rainy Lake Deep
Water Quality Trend: Improving
Based on 7 years of monitoring (2013–2019).
Water clarity
Improving7 years
Nearby Lakes in Missoula County
Frequently asked questions about Rainy Lake Deep
Where is Rainy Lake Deep?
- Rainy Lake Deep is a lake in Missoula County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.
What is the water quality of Rainy Lake Deep?
- Rainy Lake Deep in Missoula County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Water clarity: 18.9 ft visibility.
Is Rainy Lake Deep safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Rainy Lake Deep?
- The available depth estimate for Rainy Lake Deep is shallower than its measured water clarity, which cannot be right, so no depth is shown.
Are there campgrounds on Rainy Lake Deep?
- Rainy Lake Deep has 1 public campground from USGS The National Map within 5 km, including Rainy Lake Campground. 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
62 measurements from 1 monitoring station, 2013–2019. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Montana Volunteer Water Quality Monitoring
MTVOLWQM_WQX62 samples · 2013–2019
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)
Public campgrounds from USGS The National Map Structures, within about 3 miles