Where is Altamont Reservoir?

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

How deep is Altamont Reservoir?

Altamont Reservoir has a maximum depth of 29 feet and an average depth of 17 feet. The lake covers 42 acres.

Are there boat ramps on Altamont Reservoir?

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

Can I fish at Altamont Reservoir?

Altamont Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Illinois's fish and wildlife agency, so check its current regulations before you go.

Altamont Reservoir

Effingham County, Illinois42 acresView map Directions

No nutrient or algae sampling on record from Illinois EPA for this lake.

Max depth

29 ft

Bathymetric survey

Area

42 acres

Surface area

Shoreline

3.7 mi

Measured length

Impaired · Mercury
29 ft max depth
Public access

See the measurements Directions Where to stay

Altamont Reservoir in Effingham County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Maximum depth: 29 ft. Surface area: 42 acres.

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Altamont Reservoir is a 42-acre lake in Effingham County, Illinois with a maximum depth of 29 feet (17-foot average). Limited fish-species data available. Public access is available with 1 public boat landing.

Source: EPA Water Quality Portal sampling records, Illinois EPA. Methodology: how these readings are compared.

What Altamont Reservoir is good for

From access and monitoring records, not editorial picks.

Boat launch1 documented ramp

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Altamont Reservoir is listed impaired under Clean Water Act §303(d) (IR 5) for mercury, nutrients (phosphorus, nitrogen). Check local advisories before you swim.

Whether Altamont Reservoir is safe to swim in today is a call for the Illinois 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 Altamont Reservoir

These are the measurements Illinois EPA publishes for Altamont 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. TSI undefined.

Ask about Altamont Reservoir

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

Lake Details

Max depth

29 ft

Average depth

17 ft

Surface area

42 acres

Shoreline

3.7 mi

Public access

Yes

Listed by Illinois EPA

Recreation & Access

Boat Landings

Yes

Public Access

Altamont ReservoirPublic

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

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Stays near Altamont Reservoir

Compare lakeside cabins, hotels, and vacation rentals near Altamont Reservoir in Effingham County, Illinois — 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.

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Fishing Altamont Reservoir

→ Altamont Reservoir fishing regulations (limits, seasons, special rules)

EPA Impairment Status

Altamont Reservoir is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).

Causes of impairment

MercuryNutrients (phosphorus, nitrogen)

Designated uses not supporting: Fish consumption, Other.

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

Source: EPA ATTAINS assessment unit IL_RCJ · Official waterbody report

Nearby Lakes in Effingham County

Lake Sara7.9 miView →Sara Lake2.2 ft clear · Hypereutrophic8.1 miView →Lake Pauline11 miView →Lake Nellie7 miView →Patterson Lake11.4 miView →Kinmundy Old Lake1.5 ft clear · Hypereutrophic20.4 miView →

Frequently asked questions about Altamont Reservoir

Where is Altamont Reservoir?: Altamont Reservoir is a lake in Effingham County, Illinois. Its water-quality measurements are published by Illinois EPA and shown on this page as reported.
What is the water quality of Altamont Reservoir?: Altamont Reservoir in Effingham County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Maximum depth: 29 ft. Surface area: 42 acres.
Is Altamont Reservoir safe to swim in?: Nutrient and algae readings are not a swimming clearance. Altamont Reservoir is listed impaired under Clean Water Act §303(d) (IR 5) for mercury, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
How deep is Altamont Reservoir?: Altamont Reservoir has a maximum depth of 29 feet and an average depth of 17 feet. The lake covers 42 acres.
Are there boat ramps on Altamont Reservoir?: Altamont Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Altamont Reservoir. Public access is listed as yes.
Can I fish at Altamont Reservoir?: Altamont Reservoir has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Illinois's fish and wildlife agency, so check its current regulations before you go.