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

Lost Lake

Ogle County, Illinois71 acresView map Directions

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

Area

71 acres

Surface area

Shoreline

3.7 mi

Measured length

Impaired · Algal growth

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Lost Lake in Ogle County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Surface area: 71 acres.

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Lost Lake is a 71-acre lake in Ogle County, Illinois.

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

Swimming conditions

No reading

Not rated

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

Whether Lost Lake 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 Lost Lake

These are the measurements Illinois EPA publishes for Lost Lake, 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 Lost Lake

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

Lake Details

Surface area

71 acres

Shoreline

3.7 mi

No bathymetric survey has been published for Lost Lake, so its depth is not documented here.

Stays via Stay22

Stays near Lost Lake

Compare lakeside cabins, hotels, and vacation rentals near Lost Lake in Ogle 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.

Top-rated places to stay near Lost Lake

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Fishing Lost Lake

→ Lost Lake fishing regulations (limits, seasons, special rules)

EPA Impairment Status

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

Causes of impairment

Algal growthNutrients (phosphorus, nitrogen)Turbidity

Designated uses not supporting: Other.

Source: EPA ATTAINS assessment unit IL_RPZF · Official waterbody report

Nearby Lakes in Ogle County

Lake Sule17.3 miView →Leake Lake14.8 miView →Woodhaven Lake6.7 ft clear18.1 miView →Bass Lake8.1 ft clear18.4 miView →Levings Lake26.7 miView →Baumann Park Lake10.2 ft clear · Mesotrophic30.1 miView →

Frequently asked questions about Lost Lake

Where is Lost Lake?: Lost Lake is a lake in Ogle County, Illinois. Its water-quality measurements are published by Illinois EPA and shown on this page as reported.
What is the water quality of Lost Lake?: Lost Lake in Ogle County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Surface area: 71 acres.
Is Lost Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Lost Lake is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, nutrients (phosphorus, nitrogen), turbidity. Check local advisories before you swim.