Is Longer Lake safe to swim in?

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

Nipissing District County, Ontario · Water Quality Report Card

Longer Lake

Grade B — Good

Oligotrophic

Longer Lake in Nipissing District, Ontario received a water quality grade of B (Good). Water clarity: 2.6 m visibility. Phosphorus: 7 µg/L.

Clarity: 2.6 m
Type: Oligotrophic

Where to stay →Safe to swim?

Longer Lake is a cold, clear oligotrophic lake in Nipissing District County, Ontario. Water quality is graded B based on 2 sampling years through 2024. Compared to the 280 other monitored lakes in Nipissing District County, Longer Lake ranks #219 for water quality.

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

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Swimming Safety

Good for swimming, clear water with low algae levels

Water Quality Grade: B, Good

Moderate clarity, visible to about 8.5 ft. Phosphorus level: 7 µg/L. Trophic State Index: 39.

Metric	Value	Grade
Water Clarity (Secchi Depth)	2.6 m	C
Phosphorus	7 µg/L	A
Chlorophyll-a (Algae)	No data
Trophic State Index (TSI)	39	Oligotrophic

Low nutrients, clear water, excellent for swimming

Where to stay near Longer Lake

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Fishing Longer Lake

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

Location

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County Ranking

Ranked #219 of 281 lakes in Nipissing District

Cleaner Lakes Within 30 Miles

Longer Lake holds Grade B. 4 nearby lakes hold higher grades.

See full comparison →

Nearby Lakes in Nipissing District

Explore Longer Lake across LakeGrade

Lake Fishing Forecast

Species activity outlook by water temperature and season

Oligotrophic Lakes

Low nutrients, clear water, excellent for swimming

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Other Grade B Lakes in Ontario

Haliburton · 2.8 m

Haliburton · 2.8 m

Haliburton · 2.5 m

Haliburton · 6 m

Haliburton · 2.1 m

Parry Sound District · 3 m

Oligotrophic Lakes in Ontario

Luck Lake Crown Lake Lousia Lake Wolf Lake

More records, surveys & data sources

Where this data comes from

Measurements for Longer 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:

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