Loch Ayr Lake
Ringgold County, WisconsinEutrophic
Loch Ayr Lake is a 78-acre productive, nutrient-rich eutrophic lake in Ringgold County, IA. Water quality is graded D based on 2 sampling years through 2022. Compared to the 1 other monitored lakes in Ringgold County, Loch Ayr Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2022-09-06. Grade methodology: LakeGrade methodology.
Swimming Safety
Swimming not recommended, poor water quality with high algae risk
Water Quality Grade: D, Poor
Very murky, less than 2 ft of visibility. Chlorophyll-a: 29.7 µg/L. Trophic State Index: 66.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2 ft | F |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | 29.7 µg/L | D |
| Trophic State Index (TSI) | 66 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 78 acres |
Location
County Ranking
Ranked #1 of 2 lakes in Ringgold County
Cleaner Lakes Within 30 Miles
Loch Ayr Lake holds Grade D. One nearby lake has a higher grade.
See full comparison →Nearby Lakes in Ringgold County
More Wisconsin Lake Rankings
Other Grade D Lakes in Wisconsin
Eutrophic Lakes in Wisconsin
Reservoir Info (USACE NID)
Loch Ayr Lake is a man-made reservoir impounded by the Mount Ayr Reservoir Dam (completed 1930), built primarily for water supply on the TR-WALNUT CREEK; earth-type dam, 40 ft tall and 1,200 ft long.
- Surface area
- 78 ac
- Normal storage
- 780 ac-ft
- Max storage
- 1,410 ac-ft
- Drainage area
- 4.05 sq mi
- Hazard class
- Significant
- Owner
- City of Mounty Ayr
Source: USACE National Inventory of Dams, NID ID IA01370 · Operator website
EPA Impairment Status
Loch Ayr 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-GRA-1381 · Official waterbody report
Data Sources
Water quality data from the EPA Water Quality Portal
Impairment status from EPA ATTAINS 303(d) database
Grading methodology based on Metropolitan Council standards
Most recent sample: 2022-09-06
Monitoring stations: 1