What is the cleanest lake in Washington County, Minnesota?

Square Lake in Washington County has the cleanest nutrient and algae readings in Washington County, Minnesota, with 17 feet of measured 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 separately. Lakes without enough recent samples are listed without a condition class rather than ranked low. Source data comes from the EPA Water Quality Portal.

Cleanest Lakes in Washington County, Minnesota

Square Lake in Washington County leads the rankings on measured clarity and nutrients and 17 ft of clarity. Below are the top 43 cleanest monitored lakes in Washington County, Minnesota, ranked on EPA nutrient and algae measurements.

Ranked List

#	Lake	County	Clarity	Phosphorus	Algae
1	Square Lake	Washington	17 ft	9 µg/L	2.9 µg/L
2	Big Marine Lake	Washington	12 ft	13 µg/L	4.6 µg/L
3	White Bear Lake	Washington	14.4 ft	15 µg/L	2.7 µg/L
4	Pool	Washington	5.9 ft	31.1 µg/L	-
5	Clear Lake	Washington	6.2 ft	33 µg/L	6.9 µg/L
6	Pool of Lake St Croix	Washington	4.3 ft	39.2 µg/L	-
7	Tanners Lake	Washington	6.6 ft	30 µg/L	13.1 µg/L
8	Unnamed Lake	Washington	3 ft	77 µg/L	28.5 µg/L
9	Battle Creek Lake	Washington	7.2 ft	52 µg/L	9.7 µg/L
10	Carver Lake	Washington	7.4 ft	43 µg/L	12.2 µg/L
11	Mooers Lake	Washington	-	-	-
12	Baldwin Lake	Washington	-	-	-
13	Conley Lake	Washington	-	-	-
14	Sea Lake	Washington	-	-	-
15	Clear Lake	Washington	-	-	-
16	Long Lake	Washington	-	-	-
17	Lake Alice	Washington	-	-	-
18	Long Lake	Washington	-	-	-
19	Mud Lake	Washington	-	-	-
20	Barker Lake	Washington	-	-	-
21	Maple Marsh Lake	Washington	-	-	-
22	Turtle Lake	Washington	-	-	-
23	Bass Lake	Washington	-	-	-
24	Goggins Lake	Washington	-	-	-
25	Lynch Lake	Washington	-	-	-
26	Long Lake	Washington	-	-	-
27	Round Lake	Washington	-	-	-
28	Mann Lake	Washington	-	-	-
29	Louise Lake	Washington	-	-	-
30	Silver Lake	Washington	-	-	-
31	Loon Lake	Washington	-	-	-
32	Bailey Lake	Washington	-	-	-
33	Goose Lake	Washington	-	-	-
34	Clear Lake	Washington	-	-	-
35	McDonald Lake	Washington	-	-	-
36	Twin Lakes	Washington	-	-	-
37	Long Lake	Washington	-	-	-
38	Long Lake	Washington	-	-	-
39	Long Lake	Washington	-	-	-
40	Egg Lake	Washington	-	-	-
41	Rice Lake	Washington	-	-	-
42	Horseshoe Lake	Washington	-	-	-
43	Mud Lake	Washington	-	-	-

Ranked List

More Answers for Washington County, Minnesota