What is the cleanest lake in Northumberland County, Ontario?

Lake Seymour in Northumberland County is the cleanest lake on the readings in Northumberland County, Ontario with an EPA water-quality readings of — and 5.6 feet of water clarity.

How are these rankings calculated?

Nutrients and algae, total phosphorus, nitrogen, chlorophyll-a and turbidity, are read against EPA National Lakes Assessment 2022 condition classes for that lake’s ecoregion. Water clarity (Secchi depth) is measured and shown; it is not the letter. Lakes without enough recent samples are UNRATED, not given an F. Source data comes from the EPA Water Quality Portal.

Cleanest Lakes in Northumberland County, Ontario

Lake Seymour in Northumberland County leads the rankings on measured clarity and nutrients and 5.6 ft of clarity. Below are the top 2 cleanest monitored lakes in Northumberland County, Ontario, ranked by EPA water quality score.

Ranked List

#	Lake	County	Clarity	Phosphorus	Algae
1	Lake Seymour	Northumberland	—	5.6 ft	22.8 µg/L	-
2	Little Lake	Northumberland	—	4.9 ft	9.8 µg/L	-

Ranked List

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