Lake Ahquabi
Warren County, WisconsinEutrophic
Lake Ahquabi is a 113-acre productive, nutrient-rich eutrophic lake in Warren County, IA. Water quality is graded F based on 2 sampling years through 2024. Compared to the 1 other monitored lakes in Warren County, Lake Ahquabi ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2024-06-18. Grade methodology: LakeGrade methodology.
Swimming Safety
Avoid swimming, very poor water quality, potential algae toxins
Water Quality Grade: F, Very Poor
Very murky, less than 1.8 ft of visibility. Chlorophyll-a: 42.1 µg/L. Trophic State Index: 68.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.8 ft | F |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | 42.1 µg/L | F |
| Trophic State Index (TSI) | 68 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 113 acres |
Location
County Ranking
Ranked #2 of 2 lakes in Warren County
Cleaner Lakes Within 30 Miles
Lake Ahquabi holds Grade F. 3 nearby lakes hold higher grades.
- BDale Maffitt ReservoirDallas County · 18.5 mi · Two grade letters higher (F → B)
- DHooper Pond LakeWarren County · 1.1 mi · Higher grade (F → D)
- DEaster LakePolk County · 17.5 mi · Higher grade (F → D)
Nearby Lakes in Warren County
More Wisconsin Lake Rankings
Other Grade F Lakes in Wisconsin
Eutrophic Lakes in Wisconsin
Reservoir Info (USACE NID)
Lake Ahquabi is a man-made reservoir impounded by the Lake Ahquabi Dam (completed 1935), built primarily for recreation on the TR- SQUAW CREEK; earth-type dam, 43 ft tall and 1,020 ft long.
- Surface area
- 113 ac
- Normal storage
- 1,280 ac-ft
- Max storage
- 2,395 ac-ft
- Drainage area
- 5.16 sq mi
- Hazard class
- Significant
- Owner
- Iowa Department of Natural Resources
Source: USACE National Inventory of Dams, NID ID IA01131 · Operator website
EPA Impairment Status
Lake Ahquabi 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-1080 · 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: 2024-06-18
Monitoring stations: 1