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

Williams County Lake Quality

North Dakota, 25 lakes, measured by ND DEQ

The county-level average smooths over real differences — a single agricultural watershed near the southwest corner can pull the average down even if the rest of the county runs clean. 6 of those lakes carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. The county's readings sit in the middle of the North Dakota range, with one or two lakes pulling the average up or down depending on year.

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 Kota Ray Dam Lake.

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Quick Answers for Williams County

Cleanest lakes in Williams County →Cleanest lakes in North Dakota →Best swimming lakes in North Dakota →

Planning a trip? Check special fishing regulations for Kota Ray Dam Lake — or check the official North Dakota fishing regulations.

All Lakes in Williams County

25 lakes · 6 ranked on readings, 19 without enough sampling6 lakes ranked on readings · 19 without enough sampling, hidden

Include not-rated lakes (19)

#	Lake	Clarity	Phosphorus	Algae	Trophic	Max Depth	Access
1	Kota Ray Dam LakeWilliams	7.7 ft	22 µg/L	3.5 µg/L	No recent samples	No recent samples	✓ Public
2	Blacktail Dam LakeWilliams	7.2 ft	53 µg/L	8.6 µg/L	No recent samples	No recent samples	✓ Public
3	Kettle LakeWilliams	5.3 ft	37 µg/L	3.9 µg/L	No recent samples	No recent samples	✓ Public
4	Mcleod ReservoirWilliams	5.4 ft	570.5 µg/L	16.5 µg/L	No recent samples	No recent samples	✓ Public
5	Epping-Springbrook Dam-Deepest LakeWilliams	4.9 ft	689.5 µg/L	20.4 µg/L	No recent samples	No recent samples	✓ Public
6	Tioga Dam LakeWilliams	2.2 ft	182 µg/L	20 µg/L	No recent samples	No recent samples	✓ Public
	Trenton LakeWilliams	1.5 ft	44 µg/L	4.2 µg/L	No recent samples	No recent samples	✓ Public
	Epping-Springbrook Dam-Littoral LakeWilliams	No recent samples	766.5 µg/L	3.6 µg/L	No recent samples	No recent samples	Not recorded
	Epping-Springbrook Dam-S Inlet LakeWilliams	No recent samples	699.5 µg/L	18.2 µg/L	No recent samples	No recent samples	Not recorded
	Lone Tree LakeWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Cottonwood LakeWilliams	No recent samples	No recent samples	No recent samples	No recent samples	13.4 ft	✓ Public
	Alkali LakeWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Shirley LakeWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Johnny Anderson SloughWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Lake ZahlWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Horseshoe LakeWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Chase Lake State Game Management AreaWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Sueet SloughWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Stink LakeWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Twin LakesWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Green LakeWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Holm LakeWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Peterson SloughWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Tom Berg LakeWilliams	No recent samples	No recent samples	No recent samples	No recent samples	No recent samples	Not recorded
	Helle SloughWilliams	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 North Dakota Department of Environmental Quality. See data sources.