Long Lake
Long Lake in Sunflower County, Mississippi has a water quality grade of F (Algae-prone). Water clarity: 1.5 ft visibility. Phosphorus: 55 µg/L. Chlorophyll-a (algae): 46.8 µg/L.
- Clarity
- 1.5 ft
- Type
- Hypereutrophic
Grade F measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near Long Lake →
Long Lake is a highly nutrient-loaded hypereutrophic lake in Sunflower County, Mississippi. Water quality is graded F based on 2 sampling years through 2021.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2021-10-19. Grade methodology: LakeGrade methodology.
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Swimming Safety
Grade onlyAlgae risk
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Algae and nutrients are often high — check current advisories before swimming. Skip the water if you see scum or a paint-like bloom
Water Quality Grade: F (Algae-prone)
Very murky, less than 1.5 ft of visibility. Phosphorus level: 55 µg/L. Chlorophyll-a: 46.8 µg/L. Trophic State Index: 67.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.5 ft | Not graded |
| Phosphorus | 55 µg/L | Fair |
| Chlorophyll-a (Algae) | 46.8 µg/L | Poor |
| Trophic State Index (TSI) | 67 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Where to stay near Long Lake
Compare lakeside cabins, hotels, and vacation rentals near Long Lake in Sunflower County, Mississippi — 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 grade measures nutrients and algae, not lodging — cabins and rentals around Long Lake are listed below.
Top-rated places to stay near Long Lake
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Fishing Long Lake
County Ranking
Ranked #1 of 1 lakes in Sunflower County
Nearby Lakes in Sunflower County
Frequently asked questions about Long Lake
Where is Long Lake?
- Long Lake is a lake in Sunflower County, Mississippi. LakeQuality grades it F for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Long Lake?
- Long Lake in Sunflower County, Mississippi has a water quality grade of F (Algae-prone). Water clarity: 1.5 ft visibility. Phosphorus: 55 µg/L. Chlorophyll-a (algae): 46.8 µg/L.
Is Long Lake safe to swim in?
- Algae and nutrients are often high — check current advisories before swimming. Skip the water if you see scum or a paint-like bloom. Long Lake has a water quality grade of F (Algae-prone). Algae concentration (chlorophyll-a) is 46.8 µg/L. Always check local health department advisories before swimming.
Explore Long Lake across LakeGrade
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Other Grade F Lakes in Mississippi
Hypereutrophic Lakes in Mississippi
Where this data comes from
53 measurements from 1 monitoring station, 2020–2021. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- MISSISSIPPI DEPARTMENT OF ENVIRONMENTAL QUALITY
21MSWQ_WQX53 samples · 2020–2021
Analytical methods
- Phosphorus by Colorimetry
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.