Lake Orient
Adair County, WisconsinHypereutrophic
Lake Orient is a 23-acre highly nutrient-loaded hypereutrophic lake in Adair County, IA. Water quality is graded F based on 2 sampling years through 2024. Compared to the 4 other monitored lakes in Adair County, Lake Orient ranks #5 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2024-09-29. 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 1.3 ft of visibility. Chlorophyll-a: 110 µg/L. Trophic State Index: 75.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.3 ft | F |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | 110 µg/L | F |
| Trophic State Index (TSI) | 75 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 23.4 acres |
Location
County Ranking
Ranked #5 of 5 lakes in Adair County
Cleaner Lakes Within 30 Miles
Lake Orient holds Grade F. 2 nearby lakes hold higher grades.
- CMormon Trail LakeAdair County · 10.9 mi · Two grade letters higher (F → C)
- DNodaway LakeAdair County · 7.2 mi · Higher grade (F → D)
Nearby Lakes in Adair County
More Wisconsin Lake Rankings
Other Grade F Lakes in Wisconsin
Hypereutrophic Lakes in Wisconsin
Reservoir Info (USACE NID)
Lake Orient is a man-made reservoir impounded by the Orient Lake Dam (completed 1969), built primarily for water supply on the TR-EAST NODAWAY RIVER; earth-type dam, 23 ft tall and 867 ft long.
- Surface area
- 23.4 ac
- Normal storage
- 135 ac-ft
- Max storage
- 398 ac-ft
- Drainage area
- 0.94 sq mi
- Hazard class
- Significant
- Owner
- City of Orient
All listed purposes: Water Supply;Recreation.
Source: USACE National Inventory of Dams, NID ID IA00033 · Operator website
EPA Impairment Status
Lake Orient 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-NOD-1396 · 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: 2024-09-29
Monitoring stations: 1