Prairie Rose Lake
Shelby County, Iowa200 acresView mapDirections
Nutrients and algae run well above the regional average.
- Hypereutrophic
- Impaired · Algal growth
- #2 of 6 in the county
Prairie Rose Lake in Shelby County, Iowa has a water quality grade of F (Algae-prone). Water clarity: 1.6 ft visibility. Phosphorus: 159 µg/L. Chlorophyll-a (algae): 73.6 µg/L. Surface area: 200 acres.
- Clarity
- 1.6 ft
- Typical in September
- 71°F
- Area
- 200 acres
- Type
- Hypereutrophic
- Phosphorus
- 159 µg/L
- Chlorophyll-a
- 73.6 µg/L
- Trend
- ↓ Declining
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Stays near Prairie Rose Lake
Compare lakeside cabins, hotels, and vacation rentals near Prairie Rose Lake in Shelby 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 Prairie Rose Lake are listed below.
Top-rated places to stay near Prairie Rose Lake
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Watch Prairie Rose Lake’s letter
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Prairie Rose Lake is a 200-acre highly nutrient-loaded hypereutrophic lake in Shelby County, Iowa. Water quality is graded F based on 2 sampling years through 2024. Overall water quality is declining over recent sampling years. Compared to the 5 other monitored lakes in Shelby County, Prairie Rose Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, Iowa DNR, last sampled 2024-09-05. Grade methodology: LakeQuality methodology.
Swimming Safety
Grade onlyBacteria A · advisory
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.
Based on E. coli testing, Prairie Rose Lake never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 11 samples across 4 seasons.
This is a historical summary of past testing, not a current condition — bacteria levels change quickly, especially after rain. Always check Iowa’s current beach and health-department advisories before swimming.
Water Quality Grade: F (Algae-prone)
Very murky, less than 1.6 ft of visibility. Phosphorus 159 µg/L. Chlorophyll-a 73.6 µg/L. TSI 74. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.6 ft | Not graded |
| Phosphorus | 159 µg/L | Poor |
| Chlorophyll-a (Algae) | 73.6 µg/L | Poor |
| Trophic State Index (TSI) | 74 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Water Temperature
Prairie Rose Lake typically sits around 71°F at the surface in September. Summer average is about 78°F. Usually warmest in Jul (about 82°F) and coldest in Oct (about 57°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 38 field readings (2010–2023) via the EPA Water Quality Portal. See the full Prairie Rose Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 200 acres |
No bathymetric survey has been published for Prairie Rose Lake, so its depth is not documented here.
Fishing Prairie Rose Lake
Water Quality Trend: ↓ Declining
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.044 m/yr | 5 |
| Phosphorus | ↓ Declining | +27.3 µg/L/yr | 4 |
| Chlorophyll-a | ↑ Improving | -4.13 µg/L/yr | 5 |
Reservoir Info (USACE NID)
Prairie Rose Lake is a man-made reservoir impounded by the Prairie Rose Lake Dam (completed 1960), built primarily for recreation on the TR-EAST BR WEST NISHNABOTA; earth-type dam, 55 ft tall and 950 ft long.
- Surface area
- 200 ac
- Normal storage
- 3,602 ac-ft
- Max storage
- 6,824 ac-ft
- Drainage area
- 6.95 sq mi
- Hazard class
- Significant
- Owner
- Iowa Department of Natural Resources
Source: USACE National Inventory of Dams, NID ID IA01008 · Operator website
EPA Impairment Status
Prairie Rose Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit IA 05-NSH-1462 · Official waterbody report
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Prairie Rose Lake 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.
- Harlan City Of StpHarlan · 4.7 mi away · NPDES IA0021342MajorRecent violation
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 6 lakes in Shelby County
Nearby Lakes With Higher Grades
Prairie Rose Lake 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 Shelby County
Frequently asked questions about Prairie Rose Lake
Where is Prairie Rose Lake?
- Prairie Rose Lake is a lake in Shelby County, Iowa. LakeQuality grades it F for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Prairie Rose Lake?
- Prairie Rose Lake in Shelby County, Iowa has a water quality grade of F (Algae-prone). Water clarity: 1.6 ft visibility. Phosphorus: 159 µg/L. Chlorophyll-a (algae): 73.6 µg/L. Surface area: 200 acres.
Is Prairie Rose Lake safe to swim in?
- Based on E. coli testing, Prairie Rose Lake never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 11 samples across 4 seasons. That works out to a bacteria swim-safety grade of A — a historical summary of past testing, not a current reading. Prairie Rose Lake has a water quality grade of F (Algae-prone). Bacteria levels can spike quickly after heavy rain, so always check Iowa's current beach and health-department advisories before you swim.
What is the water temperature of Prairie Rose Lake?
- Prairie Rose Lake typically sits around 71°F at the surface in September, from 38 EPA Water Quality Portal field readings (2010–2023). That is a typical value for the month, not a live reading.
Explore Prairie Rose Lake across LakeQuality
Depth, room, public access, and the state wake-sport rules
Species activity outlook by water temperature and season
Where to stay at Iowa's top lakes, each with its grade
Very high nutrients, dense algae, poor clarity
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Where this data comes from
67 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_WQX67 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
- 2130 B ~ Nephelometric Method
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)