Lake Grassy
Lake Grassy in Highlands County, Florida is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 4.3 ft visibility. Phosphorus: 9 µg/L.
- Clarity
- 4.3 ft
- Trend
- ↓ Declining
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Why Lake Grassy has no grade
We grade a lake only when the monitoring record supports a letter: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Lake Grassy, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). Sampling here has recorded water clarity and phosphorus, but not algae (chlorophyll-a).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by FDEP and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Lake Grassy is a lake in Highlands County, Florida. Overall water quality is declining over recent sampling years.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2025-03-11. Grade methodology: LakeQuality methodology.
Watch Lake Grassy water quality
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Lake Grassy
These readings exist but are not enough for an A–F grade — see why.
Murky, only visible to about 4.3 ft. Phosphorus level: 9 µg/L. Trophic State Index: 46.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 4.3 ft | Not graded |
| Phosphorus | 9 µg/L | Not graded |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 46 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Lake Grassy
Compare lakeside cabins, hotels, and vacation rentals near Lake Grassy in Highlands County, Florida — 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 Lake Grassy
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Fishing Lake Grassy
Water Quality Trend: ↓ Declining
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.96 m/yr | 5 |
| Phosphorus | ↓ Declining | +0.5 µg/L/yr | 5 |
EPA Impairment Status
Lake Grassy is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 4A).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit FL1932A · Official waterbody report
Graded lakes near Lake Grassy
Lake Grassy has no grade, but these lakes within a short drive do.
Nearby Lakes in Highlands County
Frequently asked questions about Lake Grassy
Where is Lake Grassy?
- Lake Grassy is a lake in Highlands County, Florida. LakeQuality has not rated this lake (UNRATED) — no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years).
What is the water quality grade for Lake Grassy?
- Lake Grassy in Highlands County, Florida is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 4.3 ft visibility. Phosphorus: 9 µg/L.
Is Lake Grassy safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Lake Grassy is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Explore Lake Grassy across LakeQuality
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Where this data comes from
16 measurements from 2 monitoring stations, 2024–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Submitting organization not recorded for these samples10 samples · 2024
- Submitting organization not recorded for these samples6 samples · 2025
Monitoring station identifiers (2)
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.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database