Lake Monroe is a highly nutrient-loaded hypereutrophic lake in Union County, North Carolina. Water quality is graded F based on 2 sampling years through 2021. Compared to the 2 other monitored lakes in Union County, Lake Monroe ranks #3 for water quality.
Source: EPA Water Quality Portal sampling records, North Carolina DNR, last sampled 2021-09-29. Grade methodology: LakeGrade methodology.
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Swimming Safety
Avoid swimming, very poor water quality, potential algae toxins
Water Quality Grade: F, Very Poor
No clarity data. Phosphorus level: 110 µg/L. Chlorophyll-a: 62 µg/L. Trophic State Index: 72.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No data | |
| Phosphorus | 110 µg/L | F |
| Chlorophyll-a (Algae) | 62 µg/L | F |
| Trophic State Index (TSI) | 72 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
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Fishing Lake Monroe
Location
County Ranking
Ranked #3 of 3 lakes in Union County
Cleaner Lakes Within 30 Miles
Lake Monroe holds Grade F. 2 nearby lakes hold higher grades.
- CCity PondAnson County · 24.8 mi · Two grade letters higher (F → C)
- DLake TwittyUnion County · 7.2 mi · Higher grade (F → D)
Nearby Lakes in Union County
Explore Lake Monroe across LakeGrade
More North Carolina Lake Rankings
Top 25 by overall water quality score
Top 25 by Secchi water clarity
Grade A/B + low algae filter
Panfish-rich, public access
Full state directory
Other Grade F Lakes in North Carolina
Randolph County · Clarity: 2.5 ft
Chatham County · Clarity: 1.9 ft
Chatham County · Clarity: 1.6 ft
Cumberland County · Clarity: 3.1 ft
Chatham County · Clarity: 1.8 ft
Chatham County · Clarity: 2.3 ft
Hypereutrophic Lakes in North Carolina
More records, surveys & data sources
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Most recent sample: 2021-09-29
Monitoring stations: 2