Mckinley Lake
Union County, Iowa38 acresView mapDirections
Nutrients and algae run well above the regional average.
- Hypereutrophic
- Impaired · Algal growth
- #5 of 6 in the county
- 36 ft max depth
Mckinley Lake in Union County, Iowa has a water quality grade of F (Algae-prone). Water clarity: 1 ft visibility. Phosphorus: 150 µg/L. Chlorophyll-a (algae): 69.3 µg/L. Surface area: 38 acres.
- Clarity
- 1 ft
- Typical in September
- 76°F
- Max depth
- ~36 ft est.
- Area
- 38 acres
- Type
- Hypereutrophic
- Phosphorus
- 150 µg/L
- Chlorophyll-a
- 69.3 µg/L
- Trend
- ↑ Improving
Stays via Stay22
Stays near Mckinley Lake
Compare lakeside cabins, hotels, and vacation rentals near Mckinley Lake in Union 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 Mckinley Lake are listed below.
Top-rated places to stay near Mckinley Lake
Prices for Sep 11–13, 4 adults. Change dates on the map below.
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Free interactive depth-contour map of Mckinley Lake, reaching a maximum surveyed depth of 4 ft. Toggle Depth contours to overlay the bathymetric survey lines. Contour data from Iowa DNR.
Mckinley Lake is a 38-acre highly nutrient-loaded hypereutrophic lake in Union County, Iowa with an estimated average depth of about 36 feet. Water quality is graded F based on 2 sampling years through 2024. Overall water quality is improving over recent sampling years. Compared to the 5 other monitored lakes in Union County, Mckinley Lake ranks #5 for water quality.
Source: EPA Water Quality Portal sampling records, Iowa DNR, last sampled 2024-07-08. 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. Mckinley Lake is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, pCBs, turbidity. Check local advisories before you swim.
Water Quality Grade: F (Algae-prone)
Very murky, less than 1 ft of visibility. Phosphorus 150 µg/L. Chlorophyll-a 69.3 µg/L. TSI 75. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1 ft | Not graded |
| Phosphorus | 150 µg/L | Poor |
| Chlorophyll-a (Algae) | 69.3 µg/L | Poor |
| Trophic State Index (TSI) | 75 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Water Temperature
Mckinley Lake typically sits around 76°F at the surface in September. Summer average is about 78°F. Usually warmest in Jul (about 79°F) and coldest in Jun (about 76°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 11 field readings (2018–2023) via the EPA Water Quality Portal. See the full Mckinley Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | ~36 ft est. |
| Average Depth | ~11 ft est. |
| Surface Area | 38 acres |
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Iowa has not published bathymetry for Mckinley Lake.
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.
Fishing Mckinley Lake
Water Quality Trend: ↑ Improving
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.042 m/yr | 5 |
| Phosphorus | ↑ Improving | -15.89 µg/L/yr | 5 |
| Chlorophyll-a | ↑ Improving | -5.66 µg/L/yr | 5 |
Reservoir Info (USACE NID)
Mckinley Lake is a man-made reservoir impounded by the Mc Kinley Lake Dam (completed 1920), built primarily for recreation on the TR-WEST PLATTE RIVER; earth-type dam, 19 ft tall and 780 ft long.
- Surface area
- 38 ac
- Normal storage
- 200 ac-ft
- Max storage
- 290 ac-ft
- Drainage area
- 3.46 sq mi
- Hazard class
- Significant
- Owner
- City of Creston
Source: USACE National Inventory of Dams, NID ID IA01376 · Operator website
EPA Impairment Status
Mckinley Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit IA 05-PLA-1470 · Official waterbody report
Regulated Pollution Sources Nearby
2 EPA-permitted facilities operate within about 5 miles of Mckinley 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.
- Creston City Of StpCreston · 0.4 mi away · NPDES IA0035238MajorRecent violation
- Wdc Acquisition, Llc Dba WellmanCreston · 2.4 mi away · NPDES IA0077313
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 #5 of 6 lakes in Union County
Nearby Lakes With Higher Grades
Mckinley Lake holds Grade F. One nearby lake has a higher nutrient-and-algae grade — useful for a swim day, not a reason to skip lodging here.
See full comparison →Nearby Lakes in Union County
Frequently asked questions about Mckinley Lake
Where is Mckinley Lake?
- Mckinley Lake is a lake in Union County, Iowa. LakeQuality grades it F for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Mckinley Lake?
- Mckinley Lake in Union County, Iowa has a water quality grade of F (Algae-prone). Water clarity: 1 ft visibility. Phosphorus: 150 µg/L. Chlorophyll-a (algae): 69.3 µg/L. Surface area: 38 acres.
Is Mckinley Lake safe to swim in?
- The F is nutrients and algae, not a swimming clearance. Mckinley Lake is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, pCBs, turbidity. Check local advisories before you swim.
What is the water temperature of Mckinley Lake?
- Mckinley Lake typically sits around 76°F at the surface in September, from 11 EPA Water Quality Portal field readings (2018–2023). That is a typical value for the month, not a live reading.
How deep is Mckinley Lake?
- No published bathymetric survey covers Mckinley Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 36 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate. The lake covers 38 acres.
Explore Mckinley Lake across LakeQuality
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Where this data comes from
52 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_WQX52 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)
Lake size & watershed from HydroLAKES (HydroSHEDS)