Is Penassen Lake safe to swim in?

Good for swimming, clear water with low algae levels. Penassen Lake has an overall water quality grade of B. Always check local health department advisories before swimming.

Thunder Bay District County, Ontario · Water Quality Report Card

Penassen Lake

Grade B — Good

Mesotrophic

Penassen Lake in Thunder Bay District, Ontario received a water quality grade of B (Good). Water clarity: 2 m visibility. Phosphorus: 8.2 µg/L.

Clarity: 2 m
Type: Mesotrophic

Where to stay →Safe to swim?

Penassen Lake is a mesotrophic lake in Thunder Bay District County, Ontario. Water quality is graded B based on 2 sampling years through 2024. Compared to the 301 other monitored lakes in Thunder Bay District County, Penassen Lake ranks #258 for water quality.

Source: EPA Water Quality Portal sampling records, Ontario MECP, last sampled 2024-08-01. Grade methodology: LakeGrade methodology.

Watch Penassen Lake water quality

Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.

Swimming Safety

Good for swimming, clear water with low algae levels

Water Quality Grade: B, Good

Murky, only visible to about 6.6 ft. Phosphorus level: 8.2 µg/L. Trophic State Index: 42.

Metric	Value	Grade
Water Clarity (Secchi Depth)	2 m	D
Phosphorus	8.2 µg/L	A
Chlorophyll-a (Algae)	No data
Trophic State Index (TSI)	42	Mesotrophic

Moderate nutrients, good water quality

Where to stay near Penassen Lake

Compare lakeside cabins, hotels, and vacation rentals near Penassen Lake in Thunder Bay District, Ontario — 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 Penassen Lake

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 trip to Penassen Lake?

Get lake water-quality report cards plus the best cabin & lodging deals near Penassen Lake — straight to your inbox. No spam, unsubscribe anytime.

Fishing Penassen Lake

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

Location

Loading map…

County Ranking

Ranked #258 of 302 lakes in Thunder Bay District

Cleaner Lakes Within 30 Miles

Penassen Lake holds Grade B. 3 nearby lakes hold higher grades.

See full comparison →

Nearby Lakes in Thunder Bay District

Explore Penassen Lake across LakeGrade

Lake Fishing Forecast

Species activity outlook by water temperature and season

Mesotrophic Lakes

Moderate nutrients, good water quality

The State of Ontario's Lakes

Ontario's cleanest and most-polluted lakes, ranked

More Ontario Lake Rankings

Cleanest lakes in Ontario

Top 25 by overall water quality score

Clearest lakes in Ontario

Top 25 by Secchi water clarity

Best swimming lakes in Ontario

Grade A/B + low algae filter

Family fishing lakes in Ontario

Panfish-rich, public access

All Ontario lakes

Full state directory

Other Grade B Lakes in Ontario

Pyramid Lake

Kenora District · 2.3 m

Mercutio Lake

Rainy River District · 2 m

Savoy Lake

Kenora District · 2.2 m

Other Man Lake

Rainy River District · 3 m

Scotch Lake

Kenora District · 2.8 m

Farley Lake

Rainy River District · 1.1 m

Mesotrophic Lakes in Ontario

Pyramid Lake Mercutio Lake Savoy Lake Other Man Lake

More records, surveys & data sources

Where this data comes from

Measurements for Penassen Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.

Data Sources

Water quality data from the EPA Water Quality Portal

Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion

Most recent sample: 2024-08-01

Monitoring stations:

Where to stay near Penassen Lake →