Jette Lake
Lake County, MontanaView mapDirections
Montana DEQ publishes the water-quality measurements for Jette Lake. Here is what has been measured.
- Mesotrophic
Jette Lake in Lake County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Phosphorus: 16.6 µg/L. Chlorophyll-a (algae): 4.7 µg/L.
Jette Lake is a mesotrophic lake in Lake County, Montana. Overall water quality is improving over recent sampling years. Compared to the 17 other monitored lakes in Lake County, Jette Lake ranks #17 for water quality.
Source: EPA Water Quality Portal sampling records, Montana DEQ, last sampled 2023-08-28. Methodology: how these readings are compared.
Swimming conditions
Readings onlyElevated nutrients
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Jette 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 Jette Lake
These are the measurements Montana DEQ publishes for Jette 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. Phosphorus 16.6 µg/L. Chlorophyll-a 4.7 µg/L. TSI 45.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | No reading How deep a black-and-white disk stays visible from the surface. Higher is clearer. | |
| Total phosphorus | 16.6µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 4.7µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 45 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
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Stays near Jette Lake
Compare lakeside cabins, hotels, and vacation rentals near Jette Lake in Lake 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. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Jette Lake are listed below.
Top-rated places to stay near Jette Lake
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Fishing Jette Lake
Water Quality Trend: Improving
Based on 12 years of monitoring (2012–2023).
Water clarity
Worsening2 years
Phosphorus
Improving-1.48 µg/L/yr11 years
Chlorophyll-a
Improving-0.45 µg/L/yr12 years
Nearby Lakes in Lake County
Frequently asked questions about Jette Lake
Where is Jette Lake?
- Jette Lake is a lake in Lake County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.
What is the water quality of Jette Lake?
- Jette Lake in Lake County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Phosphorus: 16.6 µg/L. Chlorophyll-a (algae): 4.7 µg/L.
Is Jette Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Explore Jette Lake across LakeQuality
More lakes in Montana
Other Lakes in Montana
Mesotrophic Lakes in Montana
Where this data comes from
26 measurements from 1 monitoring station, 2012–2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Montana Watershed
MTWTRSHD_WQX26 samples · 2012–2023
Analytical methods
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
- 4500 N C ~ Persufate Method for Total Nitrogen
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.