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LakeQuality

Amann Reservoir

Morrow County, OhioView mapDirections

Ohio EPA publishes the water-quality measurements for Amann Reservoir. Here is what has been measured.

Phosphorus
241 µg/L
Measured by Ohio EPA
Type
Hypereutrophic
Trophic class
  • Hypereutrophic
  • Impaired · Habitat alterations
  • Public access
  • Limited data

Ask about Amann Reservoir

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

Amann Reservoir in Morrow County, Ohio has water-quality measurements published by Ohio EPA, shown here as reported. Phosphorus: 241 µg/L.

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Stays near Amann Reservoir

Compare lakeside cabins, hotels, and vacation rentals near Amann Reservoir in Morrow County, Ohio — 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 readings cover nutrients and algae, not lodging. Cabins and rentals around Amann Reservoir are listed below.

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Amann Reservoir is a highly nutrient-loaded hypereutrophic lake in Morrow County, Ohio. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 1 other monitored lakes in Morrow County, Amann Reservoir ranks #1 for water quality.

Source: EPA Water Quality Portal sampling records, Ohio EPA, last sampled 2024-10-02. Grade methodology: LakeQuality methodology.

What Amann Reservoir is good for

From access and monitoring records, not editorial picks.

  • Boat launch1 documented ramp

Swimming conditions

Readings only

Bacteria advisory

Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.

Nutrient and algae readings are not a swimming clearance. Amann Reservoir is listed impaired under Clean Water Act §303(d) (IR 4A) for habitat alterations, hydrologic alteration, nutrients (phosphorus, nitrogen), pathogens (E. coli, fecal), sediment / turbidity. Check local advisories before you swim.

Whether Amann Reservoir is safe to swim in today is a call for the Ohio Environmental Protection Agency and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Amann Reservoir

These are the measurements Ohio EPA publishes for Amann Reservoir, 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 241 µg/L. TSI 83.

MetricValueEPA condition class
Water Clarity (Secchi Depth)No recent samples
Phosphorus241 µg/LPoor
Chlorophyll-a (Algae)No recent samples
Trophic State Index (TSI)83Hypereutrophic

Very high nutrients, dense algae, poor clarity

Recreation & Access

1
Boat Landings
Yes
Public Access
  • Amann ReservoirPublic

Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps

Fishing Amann Reservoir

EPA Impairment Status

Amann Reservoir is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).

Causes of impairment

Habitat alterationsHydrologic alterationNutrients (phosphorus, nitrogen)Pathogens (E. coli, fecal)Sediment / turbidity

A Total Maximum Daily Load (TMDL) plan has been approved.

Source: EPA ATTAINS assessment unit OH050600010801 · Official waterbody report · Matched by proximity (2.65 km)

Nearby Lakes in Morrow County

Frequently asked questions about Amann Reservoir

Where is Amann Reservoir?

Amann Reservoir is a lake in Morrow County, Ohio. Its water-quality measurements are published by Ohio EPA and shown on this page as reported.

What is the water quality of Amann Reservoir?

Amann Reservoir in Morrow County, Ohio has water-quality measurements published by Ohio EPA, shown here as reported. Phosphorus: 241 µg/L.

Is Amann Reservoir safe to swim in?

Nutrient and algae readings are not a swimming clearance. Amann Reservoir is listed impaired under Clean Water Act §303(d) (IR 4A) for habitat alterations, hydrologic alteration, nutrients (phosphorus, nitrogen), pathogens (E. coli, fecal), sediment / turbidity. Check local advisories before you swim.

Are there boat ramps on Amann Reservoir?

Amann Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Amann Reservoir. Public access is listed as yes.

Where this data comes from

7 measurements from 1 monitoring station, 2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • Division of Surface water (Ohio)21OHIO_WQX7 samples · 2024

Analytical methods

  • Total Phosphorus After Block Digestion
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

Named boat-access points from the USGS National Boat Ramps inventory