Flaming Gorge Reservoir Antelope Flat
Daggett County, UtahView mapDirections
Clarity, phosphorus, and algae all sit in the cleanest band for this region.
- Oligotrophic
- #1 of 7 in the county
Flaming Gorge Reservoir Antelope Flat in Daggett County, Utah has a water quality grade of A (Excellent). Water clarity: 25.3 ft visibility. Phosphorus: 6.5 µg/L. Chlorophyll-a (algae): 1 µg/L.
- Clarity
- 25.3 ft
- Type
- Oligotrophic
- Phosphorus
- 6.5 µg/L
- Chlorophyll-a
- 1 µg/L
- Trend
- ↓ Declining
Stays via Stay22
Stays near Flaming Gorge Reservoir Antelope Flat
Compare lakeside cabins, hotels, and vacation rentals near Flaming Gorge Reservoir Antelope Flat in Daggett County, Utah — 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 Flaming Gorge Reservoir Antelope Flat
Prices for Sep 11–13, 4 adults. Change dates on the map below.
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 Utah’s top lakes →
Watch Flaming Gorge Reservoir Antelope Flat’s letter
Email me if this lake’s grade moves. Grades stay free.
Or email
Flaming Gorge Reservoir Antelope Flat is a cold, clear oligotrophic lake in Daggett County, Utah. Water quality is graded A based on 2 sampling years through 2025. Overall water quality is declining over recent sampling years. Compared to the 6 other monitored lakes in Daggett County, Flaming Gorge Reservoir Antelope Flat ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, Utah DWQ, last sampled 2025-07-10. Grade methodology: LakeQuality methodology.
What Flaming Gorge Reservoir Antelope Flat is good for
From access and monitoring records, not editorial picks.
- Clear water25.3 ft of visibility
Swimming Safety
Grade onlyLow algae
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.
The A is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
Water Quality Grade: A (Excellent)
Crystal clear, you can see 25.3 ft down. Phosphorus 6.5 µg/L. Chlorophyll-a 1 µg/L. TSI 31. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 25.3 ft | Not graded |
| Phosphorus | 6.5 µg/L | Good |
| Chlorophyll-a (Algae) | 1 µg/L | Good |
| Trophic State Index (TSI) | 31 | Oligotrophic |
Low nutrients, clear water. The letter is not a swimming clearance.
Fishing Flaming Gorge Reservoir Antelope Flat
Water Quality Trend: ↓ Declining
Based on 10 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | -0.036 m/yr | 10 |
| Phosphorus | ↓ Declining | +0.8 µg/L/yr | 2 |
| Chlorophyll-a | ↓ Declining | +0.04 µg/L/yr | 4 |
County Ranking
Ranked #1 of 7 lakes in Daggett County
Nearby Lakes in Daggett County
Frequently asked questions about Flaming Gorge Reservoir Antelope Flat
Where is Flaming Gorge Reservoir Antelope Flat?
- Flaming Gorge Reservoir Antelope Flat is a lake in Daggett County, Utah. LakeQuality grades it A for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Flaming Gorge Reservoir Antelope Flat?
- Flaming Gorge Reservoir Antelope Flat in Daggett County, Utah has a water quality grade of A (Excellent). Water clarity: 25.3 ft visibility. Phosphorus: 6.5 µg/L. Chlorophyll-a (algae): 1 µg/L.
Is Flaming Gorge Reservoir Antelope Flat safe to swim in?
- The A is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
Explore Flaming Gorge Reservoir Antelope Flat across LakeQuality
Species activity outlook by water temperature and season
Where to stay at Utah's top lakes, each with its grade
Low nutrients, clear water. The letter is not a swimming clearance.
Utah's cleanest and most-polluted lakes, ranked
More Utah Lake Rankings
Other Grade A Lakes in Utah
Oligotrophic Lakes in Utah
Where this data comes from
174 measurements from 1 monitoring station, 2012–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Utah Department Of Environmental Quality
UTAHDWQ_WQX174 samples · 2012–2025
Analytical methods
- Field Measurements
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- Turbidiy determined in the field
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.