East Lake Osceola
Clarke County, Iowa13 acresView mapDirections
Nutrients and algae run well above the regional average.
- Hypereutrophic
- Impaired · Oxygen depletion (low DO)
- #2 of 2 in the county
East Lake Osceola in Clarke County, Iowa has a water quality grade of F (Algae-prone). Water clarity: 1.2 ft visibility. Phosphorus: 268.3 µg/L. Chlorophyll-a (algae): 81.6 µg/L. Surface area: 13 acres.
- Clarity
- 1.2 ft
- Typical in September
- 74°F
- Area
- 13 acres
- Type
- Hypereutrophic
- Trend
- ↑ Improving
Stays via Stay22
Stays near East Lake Osceola
Compare lakeside cabins, hotels, and vacation rentals near East Lake Osceola in Clarke County, Iowa — 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 East Lake Osceola are listed below.
Top-rated places to stay near East Lake Osceola
Prices for Sep 11–13, 4 adults. Change dates on the map below.
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Watch East Lake Osceola’s letter
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Free interactive depth-contour map of East Lake Osceola, reaching a maximum surveyed depth of 12 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Iowa DNR.
East Lake Osceola is a 13-acre highly nutrient-loaded hypereutrophic lake in Clarke County, Iowa. Water quality is graded F based on 2 sampling years through 2024. Overall water quality is improving over recent sampling years. Compared to the 1 other monitored lakes in Clarke County, East Lake Osceola ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, Iowa DNR, last sampled 2024-09-15. Grade methodology: LakeQuality methodology.
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.
The F is nutrients and algae, not a swimming clearance. East Lake Osceola is listed impaired under Clean Water Act §303(d) (IR 5) for oxygen depletion (low DO), turbidity. Check local advisories before you swim.
Water Quality Grade: F (Algae-prone)
Very murky, less than 1.2 ft of visibility. Phosphorus 268.3 µg/L. Chlorophyll-a 81.6 µg/L. TSI 78. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.2 ft | Not graded |
| Phosphorus | 268.3 µg/L | Poor |
| Chlorophyll-a (Algae) | 81.6 µg/L | Poor |
| Trophic State Index (TSI) | 78 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Water Temperature
East Lake Osceola typically sits around 74°F at the surface in September. Summer average is about 79°F. Usually warmest in Jul (about 81°F) and coldest in May (about 68°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 32 field readings (2010–2023) via the EPA Water Quality Portal. See the full East Lake Osceola water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 13 acres |
No bathymetric survey has been published for East Lake Osceola, so its depth is not documented here.
Fishing East Lake Osceola
Water Quality Trend: ↑ Improving
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.084 m/yr | 5 |
| Phosphorus | ↑ Improving | -13.55 µg/L/yr | 4 |
| Chlorophyll-a | ↑ Improving | -15.89 µg/L/yr | 5 |
Reservoir Info (USACE NID)
East Lake Osceola is a man-made reservoir impounded by the East Lake Dam (completed 1915), built primarily for water supply on the TR-WHITE BREAST CREEK; earth-type dam, 41 ft tall and 795 ft long.
- Surface area
- 13 ac
- Normal storage
- 98 ac-ft
- Max storage
- 257 ac-ft
- Drainage area
- 0.5 sq mi
- Hazard class
- Significant
- Owner
- Clarke County Conservation Board
Source: USACE National Inventory of Dams, NID ID IA01337 · Operator website · Matched by proximity (0.08 km)
EPA Impairment Status
East Lake Osceola is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit IA 04-LDM-1065 · Official waterbody report
Regulated Pollution Sources Nearby
2 EPA-permitted facilities operate within about 5 miles of East Lake Osceola under Clean Water Act (NPDES) discharge permits, including 1 classified by the EPA as major discharger. 1 facility has a reported Clean Water Act violation in the past three years.
- Osceola City Of StpOsceola · 1.2 mi away · NPDES IA0041815MajorRecent violation
- Lift, L.L.C.Osceola · 4.5 mi away · NPDES IA0068403
Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.
County Ranking
Ranked #2 of 2 lakes in Clarke County
Nearby Lakes With Higher Grades
East Lake Osceola holds Grade F. 2 nearby lakes hold higher nutrient-and-algae grades — useful for a swim day, not a reason to skip lodging here.
See full comparison →Nearby Lakes in Clarke County
Frequently asked questions about East Lake Osceola
Where is East Lake Osceola?
- East Lake Osceola is a lake in Clarke County, Iowa. LakeQuality grades it F for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for East Lake Osceola?
- East Lake Osceola in Clarke County, Iowa has a water quality grade of F (Algae-prone). Water clarity: 1.2 ft visibility. Phosphorus: 268.3 µg/L. Chlorophyll-a (algae): 81.6 µg/L. Surface area: 13 acres.
Is East Lake Osceola safe to swim in?
- The F is nutrients and algae, not a swimming clearance. East Lake Osceola is listed impaired under Clean Water Act §303(d) (IR 5) for oxygen depletion (low DO), turbidity. Check local advisories before you swim.
What is the water temperature of East Lake Osceola?
- East Lake Osceola typically sits around 74°F at the surface in September, from 32 EPA Water Quality Portal field readings (2010–2023). That is a typical value for the month, not a live reading.
Explore East Lake Osceola across LakeQuality
More Iowa Lake Rankings
Other Grade F Lakes in Iowa
Hypereutrophic Lakes in Iowa
Where this data comes from
62 measurements from 1 monitoring station, 2020–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Iowa DNR Surface Water Monitoring Data
21IOWA_WQX62 samples · 2020–2024
Analytical methods
- Unknown
- Phosphorus by Colorimetry
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
- In-Vitro Determination of Chlorophyll
- ISU modification of APHA 2130-B
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.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Regulated discharger data from EPA ECHO (ICIS-NPDES)