Where is Fernan Lake?

Fernan Lake is a lake in Kootenai County, Idaho. Its water-quality measurements are published by Idaho DEQ and shown on this page as reported.

Fernan Lake

Kootenai County, Idaho365 acresView map Directions

No nutrient or algae sampling on record from Idaho DEQ for this lake.

Area

365 acres

Surface area

Shoreline

5.4 mi

Measured length

Impaired · Nutrients (phosphorus, nitrogen)

See the measurements Directions Where to stay

Fernan Lake in Kootenai County, Idaho has water-quality measurements published by Idaho DEQ, shown here as reported. Surface area: 365 acres.

Loading map…

Fernan Lake is a 365-acre lake in Kootenai County, Idaho.

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

Swimming conditions

No reading

Recreation use not supported

Nutrient and algae readings are not a swimming clearance. Fernan Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.

Whether Fernan Lake is safe to swim in today is a call for the Idaho Department of Environmental Quality and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

Get alerts for Fernan Lake →

Water quality measurements for Fernan Lake

These are the measurements Idaho DEQ publishes for Fernan 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 Fernan Lake

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

Lake Details

Surface area

365 acres

Shoreline

5.4 mi

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

Stays via Stay22

Stays near Fernan Lake

Compare lakeside cabins, hotels, and vacation rentals near Fernan Lake in Kootenai County, Idaho — 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 Fernan Lake

Prices for Oct 16–18, 4 adults. Change dates on the map below.

Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.

Planning a whole trip? See where to stay at Idaho’s top lakes →

Follow Fernan Lake’s readings

Email me when new measurements post for this lake. Updates stay free.

Or email

Fishing Fernan Lake

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

EPA Impairment Status

Fernan Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 4A).

Causes of impairment

Nutrients (phosphorus, nitrogen)

Designated uses not supporting: Recreation.

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

Source: EPA ATTAINS assessment unit ID17010303PN033_03L · Official waterbody report

Nearby Lakes in Kootenai County

Usgs Lake6 miView →Avondale Lake7 miView →Lake Hayden7.6 miView →Alpine Lake9.9 miView →Ideq Lake9.4 miView →Thompson Lake12.7 miView →

Frequently asked questions about Fernan Lake

Where is Fernan Lake?: Fernan Lake is a lake in Kootenai County, Idaho. Its water-quality measurements are published by Idaho DEQ and shown on this page as reported.
What is the water quality of Fernan Lake?: Fernan Lake in Kootenai County, Idaho has water-quality measurements published by Idaho DEQ, shown here as reported. Surface area: 365 acres.
Is Fernan Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Fernan Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.