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LakeQuality

Monroe City Lake B

Monroe County, MissouriView mapDirections

Missouri DNR publishes the water-quality measurements for Monroe City Lake B. Here is what has been measured.

Phosphorus
44 µg/L
Measured by Missouri DNR
Max depth
~35 ft est.
GLOBathy model
  • Impaired · Algal growth
  • 35 ft max depth
  • Limited data

Ask about Monroe City Lake B

Answers come straight from the public measurements and survey records on this page.

Monroe City Lake B in Monroe County, Missouri has water-quality measurements published by Missouri DNR, shown here as reported. Phosphorus: 44 µg/L.

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Monroe City Lake B is a lake in Monroe County, Missouri with an estimated average depth of about 35 feet.

Source: EPA Water Quality Portal sampling records, Missouri DNR, last sampled 2025-07-28. Grade methodology: LakeQuality methodology.

Swimming conditions

No reading

Limited data

Nutrient and algae readings are not a swimming clearance. Monroe City Lake B is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth. Check local advisories before you swim.

Whether Monroe City Lake B is safe to swim in today is a call for the Missouri Department of Natural Resources and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Monroe City Lake B

These are the measurements Missouri DNR publishes for Monroe City Lake B, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.

No clarity data. Phosphorus 44 µg/L. TSI 59.

MetricValueEPA condition class
Water Clarity (Secchi Depth)No recent samples
Phosphorus44 µg/LMeasured, not scored
Chlorophyll-a (Algae)No recent samples
Trophic State Index (TSI)59Eutrophic

High nutrients, frequent algae, reduced clarity

Lake Details

CharacteristicValue
Maximum Depth~35 ft est.
Average Depth~7 ft est.

Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Missouri has not published bathymetry for Monroe City Lake B.

Lake Size & Watershed

Watershed (drainage) area
6 sq mi
Surface area
54 acres
Shoreline
1.4 mi
Elevation
705 ft

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 Monroe City Lake B

EPA Impairment Status

Monroe City Lake B is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).

Causes of impairment

Algal growth

Source: EPA ATTAINS assessment unit MO_7034.00 · Official waterbody report · Matched by proximity (0.46 km)

Nearby Lakes in Monroe County

Frequently asked questions about Monroe City Lake B

Where is Monroe City Lake B?

Monroe City Lake B is a lake in Monroe County, Missouri. Its water-quality measurements are published by Missouri DNR and shown on this page as reported.

What is the water quality of Monroe City Lake B?

Monroe City Lake B in Monroe County, Missouri has water-quality measurements published by Missouri DNR, shown here as reported. Phosphorus: 44 µg/L.

Is Monroe City Lake B safe to swim in?

Nutrient and algae readings are not a swimming clearance. Monroe City Lake B is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth. Check local advisories before you swim.

How deep is Monroe City Lake B?

No published bathymetric survey covers Monroe City Lake B, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 35 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.

Where this data comes from

1 measurement from 1 monitoring station, 2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • Missouri Dept. of Natural ResourcesMDNR1 sample · 2025

Analytical methods

  • Nitrogen and Phosphorus, Total, Whole-water, Alkaline Persulfate Digest
Monitoring station identifiers (1)

EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.

Other records on this page

Impairment status from EPA ATTAINS 303(d) database

Lake size & watershed from HydroLAKES (HydroSHEDS)