Lake Mattie
Lake Mattie in Polk County, Florida is not rated for water quality — its monitoring record does not meet the evidence bar.
- Trend
- ↑ Improving
Next lake in Polk County
Swipe left or right on this bar to open the next or previous lake.
Why Lake Mattie 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 Mattie, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years).
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 Mattie is a lake in Polk County, Florida. Overall water quality is improving over recent sampling years.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2023-02-07. Grade methodology: LakeQuality methodology.
Watch Lake Mattie water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Lake Mattie
These readings exist but are not enough for an A–F grade — see why.
No clarity data.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples |
Where to stay near Lake Mattie
Compare lakeside cabins, hotels, and vacation rentals near Lake Mattie in Polk 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 Mattie
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Florida’s top lakes →
Fishing Lake Mattie
Water Quality Trend: ↑ Improving
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.018 m/yr | 6 |
| Phosphorus | ↑ Improving | -5.53 µg/L/yr | 6 |
Nearby Lakes in Polk County
Frequently asked questions about Lake Mattie
Where is Lake Mattie?
- Lake Mattie is a lake in Polk 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 Mattie?
- Lake Mattie in Polk County, Florida is not rated for water quality — its monitoring record does not meet the evidence bar.
Is Lake Mattie safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Lake Mattie 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 Mattie across LakeQuality
More Florida Lake Rankings
Other Lakes in Florida
Where this data comes from
2 measurements from 1 monitoring station, 2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Submitting organization not recorded for these samples2 samples · 2023
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.