Lamar City Lk. East Arm Lake
Barton County, MissouriView mapDirections
Nutrients and algae run well above the regional average.
- Hypereutrophic
- Impaired · Nutrients (phosphorus, nitrogen)
- #2 of 6 in the county
- Limited data
Lamar City Lk. East Arm Lake in Barton County, Missouri has a water quality grade of F (Algae-prone). Water clarity: 1.9 ft visibility. Phosphorus: 72.3 µg/L. Chlorophyll-a (algae): 32.1 µg/L.
- Clarity
- 1.9 ft
- Typical in August
- 80°F
- Type
- Hypereutrophic
- Phosphorus
- 72.3 µg/L
- Chlorophyll-a
- 32.1 µg/L
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Stays near Lamar City Lk. East Arm Lake
Compare lakeside cabins, hotels, and vacation rentals near Lamar City Lk. East Arm Lake in Barton County, Missouri — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water. The water-quality grade measures nutrients and algae, not lodging — cabins and rentals around Lamar City Lk. East Arm Lake are listed below.
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Lamar City Lk. East Arm Lake is a highly nutrient-loaded hypereutrophic lake in Barton County, Missouri. Water quality is graded F based on 2 sampling years through 2020. Compared to the 5 other monitored lakes in Barton County, Lamar City Lk. East Arm Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, Missouri DNR, last sampled 2020-11-04. Grade methodology: LakeQuality methodology.
Swimming Safety
Grade onlyLimited data
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
The F is nutrients and algae, not a swimming clearance. Lamar City Lk. East Arm Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Water Quality Grade: F (Algae-prone)
Very murky, less than 1.9 ft of visibility. Phosphorus 72.3 µg/L. Chlorophyll-a 32.1 µg/L. TSI 66. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.9 ft | Not graded |
| Phosphorus | 72.3 µg/L | Poor |
| Chlorophyll-a (Algae) | 32.1 µg/L | Poor |
| Trophic State Index (TSI) | 66 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Water Temperature
Lamar City Lk. East Arm Lake typically sits around 80°F at the surface in August. Summer average is about 82°F. Usually warmest in Jul (about 84°F) and coldest in Aug (about 80°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 12 field readings (2020–2020) via the EPA Water Quality Portal. See the full Lamar City Lk. East Arm Lake water temperature breakdown →
Fishing Lamar City Lk. East Arm Lake
EPA Impairment Status
Lamar City Lk. East Arm Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 4A).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MO_7356.00 · Official waterbody report · Matched by proximity (0.07 km)
County Ranking
Ranked #2 of 6 lakes in Barton County
Nearby Lakes in Barton County
Frequently asked questions about Lamar City Lk. East Arm Lake
Where is Lamar City Lk. East Arm Lake?
- Lamar City Lk. East Arm Lake is a lake in Barton County, Missouri. LakeQuality grades it F for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Lamar City Lk. East Arm Lake?
- Lamar City Lk. East Arm Lake in Barton County, Missouri has a water quality grade of F (Algae-prone). Water clarity: 1.9 ft visibility. Phosphorus: 72.3 µg/L. Chlorophyll-a (algae): 32.1 µg/L.
Is Lamar City Lk. East Arm Lake safe to swim in?
- The F is nutrients and algae, not a swimming clearance. Lamar City Lk. East Arm Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
What is the water temperature of Lamar City Lk. East Arm Lake?
- Lamar City Lk. East Arm Lake typically sits around 80°F at the surface in August, from 12 EPA Water Quality Portal field readings (2020–2020). That is a typical value for the month, not a live reading.
Explore Lamar City Lk. East Arm Lake across LakeQuality
Species activity outlook by water temperature and season
Where to stay at Missouri's top lakes, each with its grade
Very high nutrients, dense algae, poor clarity
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Where this data comes from
48 measurements from 1 monitoring station, 2020. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Univ. of Missouri, Columbia
UMC48 samples · 2020
Analytical methods
- Depth, Secchi disk in meters
- 4500 P E ~ Phosphorus in Water by Colorimetry- Ascorbic Acid Method
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database