Late afternoon sun over Slim Lake, scattering a bright path across wind-textured water

Washington County Lake Quality

Minnesota, 108 lakes, measured by Minnesota PCA

Washington County in Minnesota carries 108 monitored lakes — one of the lake-richer counties in our dataset. Coverage that dense usually reflects active lake-association sampling alongside state-agency monitoring. 70 of those lakes carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. For Washington County the spread behind the average matters more than the average itself: a few nutrient-rich lakes among many clear ones produce the same figure as the inverse.

The county's lakes lean shallow, which makes the readings sensitive to wind, sediment-resuspension, and any nutrient inputs from the watershed. The cleanest measured lake is Twin Lake.

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Quick Answers for Washington County

Cleanest lakes in Washington County →Cleanest lakes in Minnesota →Best swimming lakes in Minnesota →

Planning a trip? Check special fishing regulations for Twin Lake — or browse the full Minnesota regulations index.

Fishing in Washington County

Washington County Fishing Guide

Fish species and the cleanest lakes in Washington County

DNR Reports (40)

Minnesota DNR LakeFinder resources for lakes in Washington County. browse all reports →

These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).

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Fisheries Lake Survey — White Bear
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Big Marine
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Tanners
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Square
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Cloverdale
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Long
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Little Carnelian
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Lily
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — St. Croix
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Jane
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Keewahtin
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Forest
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Elmo
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Clear
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Carver
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Bone
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Big Carnelian
Fisheries Lake Survey · MN DNR LakeFinder
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Fisheries Lake Survey — Battle Creek
Fisheries Lake Survey · MN DNR LakeFinder
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Fish Stocking History — Battle Creek
Fish Stocking History · MN DNR LakeFinder
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Public Water Access Sites — Battle Creek
Public Water Access Sites · MN DNR LakeFinder
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Fish Stocking History — Big Carnelian
Fish Stocking History · MN DNR LakeFinder
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Public Water Access Sites — Big Carnelian
Public Water Access Sites · MN DNR LakeFinder
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Public Water Access Sites — Big Marine (Main Lake)
Public Water Access Sites · MN DNR LakeFinder
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Fish Stocking History — Bone
Fish Stocking History · MN DNR LakeFinder
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Public Water Access Sites — Bone
Public Water Access Sites · MN DNR LakeFinder
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Fish Stocking History — Carver
Fish Stocking History · MN DNR LakeFinder
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Fish Stocking History — Clear
Fish Stocking History · MN DNR LakeFinder
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Public Water Access Sites — Clear
Public Water Access Sites · MN DNR LakeFinder
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Fish Stocking History — Elmo
Fish Stocking History · MN DNR LakeFinder
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Public Water Access Sites — Elmo
Public Water Access Sites · MN DNR LakeFinder
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Fish Stocking History — Forest
Fish Stocking History · MN DNR LakeFinder
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Public Water Access Sites — Forest
Public Water Access Sites · MN DNR LakeFinder
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Public Water Access Sites — Grey Cloud Slough
Public Water Access Sites · MN DNR LakeFinder
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Public Water Access Sites — Jane
Public Water Access Sites · MN DNR LakeFinder
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Fish Stocking History — St. Croix
Fish Stocking History · MN DNR LakeFinder
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Public Water Access Sites — Lily
Public Water Access Sites · MN DNR LakeFinder
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Public Water Access Sites — Oneka
Public Water Access Sites · MN DNR LakeFinder
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Public Water Access Sites — Square
Public Water Access Sites · MN DNR LakeFinder
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Fish Stocking History — Tanners
Fish Stocking History · MN DNR LakeFinder
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Public Water Access Sites — Tanners
Public Water Access Sites · MN DNR LakeFinder

All Lakes in Washington County

108 lakes · 70 ranked on readings, 38 without enough sampling70 lakes ranked on readings · 38 without enough sampling, hidden

Include not-rated lakes (38)

#	Lake	Clarity	Phosphorus	Algae	Trophic	Max Depth	Access
1	Twin LakeWashington	13 ft	13 µg/L	2.8 µg/L	No recent samples	No recent samples	Carry-in
2	Clear LakeWashington	14 ft	16 µg/L	3.1 µg/L	No recent samples	27 ft	Carry-in
3	Square LakeWashington	17 ft	9 µg/L	2.9 µg/L	No recent samples	68 ft	✓ Public
4	Big Marine LakeWashington	12 ft	13 µg/L	4.6 µg/L	No recent samples	No recent samples	✓ Public
5	White Bear LakeWashington	14.4 ft	15 µg/L	2.7 µg/L	No recent samples	83 ft	✓ Public
6	Halfbreed LakeWashington	5.2 ft	9.5 µg/L	2.3 µg/L	No recent samples	34 ft	✓ Public
7	Big Carnelian LakeWashington	14.5 ft	12 µg/L	3.4 µg/L	No recent samples	66 ft	✓ Public
8	Lily LakeWashington	10.5 ft	17 µg/L	5.1 µg/L	No recent samples	51 ft	✓ Public
9	Little Carnelian LakeWashington	20 ft	9 µg/L	2.1 µg/L	No recent samples	68 ft	Carry-in
10	Elmo LakeWashington	11.1 ft	12.5 µg/L	1.6 µg/L	No recent samples	140 ft	✓ Public
11	Jane LakeWashington	13 ft	21 µg/L	3.8 µg/L	No recent samples	39 ft	✓ Public
12	Olson LakeWashington	11.2 ft	15 µg/L	2.6 µg/L	No recent samples	15 ft	Carry-in
13	White Rock LakeWashington	7.5 ft	19.5 µg/L	2 µg/L	No recent samples	No recent samples	Carry-in
14	Wood Pile LakeWashington	10 ft	20 µg/L	4.2 µg/L	No recent samples	No recent samples	Carry-in
15	Sunset LakeWashington	9.5 ft	16 µg/L	3.6 µg/L	No recent samples	17 ft	Carry-in
16	Master Man LakeWashington	4.5 ft	19 µg/L	4.3 µg/L	No recent samples	No recent samples	Carry-in
17	Pine Tree LakeWashington	8.5 ft	17 µg/L	4.1 µg/L	No recent samples	No recent samples	Carry-in
18	East Boot LakeWashington	15 ft	16 µg/L	2 µg/L	No recent samples	27 ft	Carry-in
19	Edith LakeWashington	8.2 ft	14 µg/L	3.5 µg/L	No recent samples	43 ft	Carry-in
20	Mays LakeWashington	11 ft	16 µg/L	4.1 µg/L	No recent samples	25 ft	Carry-in
21	West Boot LakeWashington	14 ft	14 µg/L	2.5 µg/L	No recent samples	34 ft	Carry-in
22	PoolWashington	5.9 ft	31.1 µg/L	No recent samples	No recent samples	78 ft	✓ Public
23	O'Connors LakeWashington	6.6 ft	32 µg/L	13.5 µg/L	No recent samples	No recent samples	Carry-in
24	Long LakeWashington	8 ft	25 µg/L	5.6 µg/L	No recent samples	25 ft	Carry-in
25	Clear LakeWashington	6.2 ft	33 µg/L	6.9 µg/L	No recent samples	28 ft	✓ Public
26	Fish LakeWashington	5 ft	26 µg/L	3.6 µg/L	No recent samples	No recent samples	✓ Public
27	Bass LakeWashington	6.5 ft	26.5 µg/L	7.6 µg/L	No recent samples	No recent samples	Carry-in
28	Pool of Lake St CroixWashington	4.3 ft	39.2 µg/L	No recent samples	No recent samples	78 ft	✓ Public
29	Lost LakeWashington	6.3 ft	25 µg/L	4.5 µg/L	No recent samples	34 ft	Carry-in
30	South Twin LakeWashington	5 ft	32 µg/L	9 µg/L	No recent samples	No recent samples	Carry-in
31	Sunfish LakeWashington	8.9 ft	25 µg/L	7.2 µg/L	No recent samples	No recent samples	Carry-in
32	Tanners LakeWashington	6.6 ft	30 µg/L	13.1 µg/L	No recent samples	46 ft	✓ Public
33	Hay LakeWashington	3.5 ft	30 µg/L	4.8 µg/L	No recent samples	No recent samples	Carry-in
34	Friedrich PondWashington	2.3 ft	60.5 µg/L	3.9 µg/L	No recent samples	No recent samples	Carry-in
35	Plaisted LakeWashington	7.3 ft	25 µg/L	3.1 µg/L	No recent samples	No recent samples	Carry-in
36	North School Section LakeWashington	7.8 ft	25.5 µg/L	8 µg/L	No recent samples	No recent samples	Carry-in
37	Lynch LakeWashington	5.8 ft	33 µg/L	9.8 µg/L	No recent samples	No recent samples	Carry-in
38	Jellums LakeWashington	6 ft	27 µg/L	8.2 µg/L	No recent samples	No recent samples	✓ Public
39	Benz LakeWashington	4.5 ft	26 µg/L	3.6 µg/L	No recent samples	No recent samples	Carry-in
40	Beutel'S PondWashington	2.5 ft	36.5 µg/L	3.2 µg/L	No recent samples	No recent samples	Carry-in
41	Demontreville LakeWashington	10.2 ft	25.5 µg/L	11 µg/L	No recent samples	24 ft	✓ Public
42	Pat LakeWashington	6.5 ft	39 µg/L	11 µg/L	No recent samples	No recent samples	Carry-in
43	Long LakeWashington	2.8 ft	47.5 µg/L	25.3 µg/L	No recent samples	60 ft	✓ Public
44	Unnamed LakeWashington	3 ft	77 µg/L	28.5 µg/L	No recent samples	60 ft	✓ Public
45	Fish LakeWashington	2 ft	98.5 µg/L	12.5 µg/L	No recent samples	No recent samples	Carry-in
46	Fish LakeWashington	6 ft	42 µg/L	12 µg/L	No recent samples	34 ft	Carry-in
47	Battle Creek LakeWashington	7.2 ft	52 µg/L	9.7 µg/L	No recent samples	15.3 ft	✓ Public
48	Mcdonald LakeWashington	5 ft	83 µg/L	26 µg/L	No recent samples	28 ft	Carry-in
49	Shields LakeWashington	4.4 ft	100.5 µg/L	19 µg/L	No recent samples	27 ft	Carry-in
50	Forest LakeWashington	5.1 ft	28 µg/L	16.5 µg/L	No recent samples	37 ft	✓ Public
51	Carver LakeWashington	7.4 ft	43 µg/L	12.2 µg/L	No recent samples	36 ft	Carry-in
52	Bone LakeWashington	5.5 ft	29 µg/L	18.5 µg/L	No recent samples	30 ft	✓ Public
53	Powers LakeWashington	5.8 ft	187 µg/L	14.5 µg/L	No recent samples	41 ft	Carry-in
54	Markgrafs LakeWashington	4.8 ft	60 µg/L	15 µg/L	No recent samples	No recent samples	Carry-in
55	Eagle Point LakeWashington	2.5 ft	62 µg/L	19.6 µg/L	No recent samples	No recent samples	Carry-in
56	Mckusick LakeWashington	6 ft	41 µg/L	10.1 µg/L	No recent samples	No recent samples	✓ Public
57	Sunnybrook LakeWashington	4.5 ft	41.5 µg/L	18.5 µg/L	No recent samples	No recent samples	Carry-in
58	Cloverdale LakeWashington	5 ft	30 µg/L	16.5 µg/L	No recent samples	28 ft	Carry-in
59	Mud LakeWashington	1.2 ft	89 µg/L	87 µg/L	No recent samples	No recent samples	Carry-in
60	Horseshoe LakeWashington	4.8 ft	40 µg/L	31 µg/L	No recent samples	11.3 ft	Carry-in
61	Colby LakeWashington	3.8 ft	61 µg/L	34.5 µg/L	No recent samples	11 ft	Carry-in
62	Sand LakeWashington	2.5 ft	53 µg/L	42.5 µg/L	No recent samples	18 ft	✓ Public
63	Goose LakeWashington	1.5 ft	101.5 µg/L	63 µg/L	No recent samples	No recent samples	Carry-in
64	Goose LakeWashington	3 ft	40 µg/L	40 µg/L	No recent samples	25 ft	✓ Public
65	Rose LakeWashington	1.8 ft	132.5 µg/L	74.5 µg/L	No recent samples	11.3 ft	Carry-in
66	Nielson LakeWashington	1.6 ft	92.5 µg/L	66.5 µg/L	No recent samples	No recent samples	Carry-in
67	S School Section LakeWashington	4 ft	42.5 µg/L	42.5 µg/L	No recent samples	26 ft	Carry-in
68	Klawitter PondWashington	1.9 ft	96 µg/L	38 µg/L	No recent samples	No recent samples	Carry-in
69	Wilmes LakeWashington	3.5 ft	66.5 µg/L	31 µg/L	No recent samples	No recent samples	Carry-in
70	Downs LakeWashington	1.8 ft	159 µg/L	68.5 µg/L	No recent samples	No recent samples	Carry-in
	Legion PondWashington	7 ft	No recent samples	No recent samples	No recent samples	No recent samples	Carry-in
	Oneka LakeWashington	4.4 ft	No recent samples	No recent samples	No recent samples	No recent samples	✓ Public
	Grey Cloud Slough LakeWashington	3.3 ft	No recent samples	No recent samples	No recent samples	No recent samples	✓ Public
	Terrapin LakeWashington	9.7 ft	No recent samples	No recent samples	No recent samples	No recent samples	Carry-in
	Kramer LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Carry-in
	Mooers LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Baldwin LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Conley LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Sea LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Clear LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Long LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	6.6 ft	Not recorded
	Lake AliceWashington	No recent samples	No recent samples	No recent samples	No recent samples	9 ft	✓ Public
	Long LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	12.1 ft	Not recorded
	Mud LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Barker LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	19.7 ft	Not recorded
	Maple Marsh LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Turtle LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	6.6 ft	Not recorded
	Bass LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	13.1 ft	Not recorded
	Goggins LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	11.5 ft	Not recorded
	Lynch LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	16.4 ft	Not recorded
	Long LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Round LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Mann LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Louise LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	8.7 ft	Not recorded
	Silver LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	6.6 ft	Not recorded
	Loon LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	13.1 ft	Not recorded
	Bailey LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Goose LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	6.6 ft	Not recorded
	Clear LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	9.8 ft	Not recorded
	McDonald LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	9.8 ft	Not recorded
	Twin LakesWashington	No recent samples	No recent samples	No recent samples	No recent samples	6.6 ft	Not recorded
	Long LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	22 ft	Not recorded
	Long LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	25 ft	Not recorded
	Long LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	34 ft	Not recorded
	Egg LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Rice LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	3.3 ft	Not recorded
	Horseshoe LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Mud LakeWashington	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded

NR = no nutrient or algae reading on record. The measurements are published as the authority reports them. Where the data comes from.

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Source: the Minnesota Pollution Control Agency and the Minnesota DNR. See data sources.