Alfalfa County, Oklahoma · Water Quality Report Card
Great Salt Plains Lake
Great Salt Plains Lake in Alfalfa County, Oklahoma is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 0.7 ft visibility.
- Clarity
- 0.7 ft
- Mean depth
- ~49 ft est.
- Type
- Hypereutrophic
- Trend
- ↑ Improving
Great Salt Plains Lake is a highly nutrient-loaded hypereutrophic lake in Alfalfa County, Oklahoma with an estimated average depth of about 49 feet. Overall water quality is improving over recent sampling years.
Source: EPA Water Quality Portal sampling records, ODEQ, last sampled 2019-07-15. Grade methodology: LakeGrade methodology.
Watch Great Salt Plains Lake water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Not rated for swimming — there is not enough monitoring data to judge this lake
Water Quality Grade: Not rated
Very murky, less than 0.7 ft of visibility. Trophic State Index: 83.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 0.7 ft | |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 83 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Lake Details
| Characteristic | Value |
|---|---|
| Average Depth | ~49 ft est. |
Depth marked “est.” is a modeled estimate from HydroLAKES, not a measured survey. Oklahoma has not published bathymetry for Great Salt Plains Lake.
Where to stay near Great Salt Plains Lake
Compare lakeside cabins, hotels, and vacation rentals near Great Salt Plains Lake in Alfalfa County, Oklahoma — 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 Great Salt Plains Lake
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 trip to Great Salt Plains Lake?
Get lake water-quality report cards plus the best cabin & lodging deals near Great Salt Plains Lake — straight to your inbox. No spam, unsubscribe anytime.
Planning a whole trip? See where to stay at Oklahoma’s top lakes →
Fishing Great Salt Plains Lake
Water Quality Trend: ↑ Improving
Based on 2 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +6 m/yr | 2 |
Location
Nearby Lakes in Alfalfa County
Explore Great Salt Plains Lake across LakeGrade
Species activity outlook by water temperature and season
Where to stay at Oklahoma's top lakes, each with its grade
Very high nutrients, dense algae, poor clarity
Oklahoma's cleanest and most-polluted lakes, ranked
More Oklahoma Lake Rankings
Other Lakes in Oklahoma
Hypereutrophic Lakes in Oklahoma
More records, surveys & data sources
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Where this data comes from
17 measurements from 3 monitoring stations, 2016–2019. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- OWRB Lakes Monitoring
OKWRB-LAKES_WQX17 samples · 2016–2019
Analytical methods
- OWRB Lakes Field Data Collection
Monitoring station identifiers (3)
Grade thresholds come from the U.S. EPA National Lakes Assessment 2022 Technical Support Document (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated.
Data Sources
Water quality data from the EPA Water Quality Portal
Lake size & watershed from HydroLAKES (HydroSHEDS)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion
Most recent sample: 2019-07-15
Monitoring stations: 3