Two canoes crossing open water between forested points in the Boundary Waters

Updated August 2026

Biggest Lake in Nebraska: Lake McConaughy (30,500 acres)

Lake McConaughy is Nebraska's largest inland lake per the USACE National Inventory of Dams (Kingsley Dam, NID ID NE01048, owner Central Nebraska Public Power & Irrigation District) — corroborated by CNPPID and Nebraska Game and Parks Commission. Below: 50 Nebraska lakes ranked by surface area.

The largest lake in Nebraska is Lake McConaughy at 30,500 acres , in Keith County, according to the USACE National Inventory of Dams (Kingsley Dam, NID ID NE01048, owner Central Nebraska Public Power & Irrigation District) — corroborated by CNPPID and Nebraska Game and Parks Commission. Lewis and Clark Lake is larger at 31,400 acres. It is a Missouri River reservoir shared with South Dakota, so it is not a lake lying entirely within Nebraska.

Lake McConaughy isn't in our water-quality index — we grade lakes with enough EPA Water Quality Portal samples to score, which leaves out many large reservoirs and border waters. The ranking below covers the 50 Nebraska lakes with nutrient and algae readings, led by Harlan County Reservoir.

Source: USACE National Inventory of Dams (Kingsley Dam, NID ID NE01048, owner Central Nebraska Public Power & Irrigation District) — corroborated by CNPPID and Nebraska Game and Parks Commission (2026-07-30). The table below ranks the Nebraska lakes in our own index by surface area.

Lakes with area data

13,600

Largest (acres)

661

Median of top 50

17/50

Reservoirs (vs natural)

Reading Nebraska's size profile

Nebraska's largest lake by surface area is Harlan County Reservoir in Harlan County, spanning 13,600 acres. Most of Nebraska's biggest waters are natural basins left by glaciers, with stable shorelines and deep main basins.

Surface area is a poor proxy for water quality on its own — a large lake can hold a clean, deep core and a nutrient-loaded bay at the same time. Each lake below links to its full page with nutrient readings, clarity, depth, and EPA impairment status. Area figures come from state DNR surveys and the USACE National Inventory of Dams; water-quality readings come from EPA and state monitoring data.

The 50 biggest lakes in Nebraska by surface area

#	Lake	County	Surface area	Max depth
1	Harlan County Reservoir	Harlan	13,600 acres	-
2	Swanson Reservoir	Hitchcock	7,940 acres	-
3	Harry Strunk Lake	Frontier	5,793 acres	-
4	Jeffrey Reservoir	Lincoln	5,756 acres	-
5	Calamus Reservoir	Garfield	5,123 acres	-
6	Hugh Butler Lake	Frontier	4,060 acres	-
7	Merritt Reservoir	Cherry	3,222 acres	-
8	Sutherland Reservoir	Lincoln	2,956 acres	31 ft
9	Sherman Reservoir	Sherman	2,868 acres	-
10	Enders Reservoir	Chase	2,557 acres	-
11	Lake Minatare	Scotts Bluff	2,195 acres	-
12	Box Butte Reservoir	Dawes	1,799 acres	-
13	Davis Creek Reservoir	Greeley	1,430 acres	-
14	Twin Lakes	Sheridan	1,307 acres	-
15	Elwood Reservoir	Gosper	1,145 acres	-
16	Dads Lake	Cherry	1,104 acres	-
17	Lake North	Platte	961 acres	-
18	South Marsh Lake	Cherry	947 acres	-
19	DeSoto Lake	Washington	860 acres	18 ft
20	Lake Babcock	Platte	846 acres	-
21	Big Alkali Lake	Cherry	813 acres	-
22	Willow Creek Reservoir	Pierce	715 acres	-
23	Mother Lake	Cherry	712 acres	-
24	Cottonwood Lake	Cherry	667 acres	20 ft
25	Lake Wanahoo	Saunders	662 acres	-
26	Alkali Lake	Cherry	661 acres	-
27	Schoonover Lake	Garden	658 acres	-
28	Lake Alice	Scotts Bluff	622 acres	-
29	Trout Lake	Cherry	550 acres	-
30	Island Lake	Garden	532 acres	7 ft
31	Dewey Lake	Cherry	524 acres	-
32	Clear Lake	Cherry	510 acres	-
33	Hackberry Lake	Cherry	501 acres	6 ft
34	Moon Lake	Brown	500 acres	-
35	Dora Lake	Holt	452 acres	-
36	Mule Lake	Cherry	434 acres	-
37	Spring Valley Lake	Grant	429 acres	-
38	Smith Lake	Sheridan	425 acres	-
39	Ashburger Lake	Garden	420 acres	-
40	Long Lake	Cherry	418 acres	-
41	Willow Lake	Brown	403 acres	10 ft
42	Swan Lake	Cherry	402 acres	-
43	George Lake	Grant	399 acres	-
44	Whitewater Lake	Cherry	379 acres	-
45	Enders Lake	Brown	377 acres	-
46	Billys Lake	Sheridan	377 acres	-
47	Red Deer Lake	Cherry	377 acres	-
48	Swan Lake	Garden	375 acres	-
49	Willow Lake	Cherry	373 acres	-
50	Peter Long Lake	Sheridan	371 acres	-

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Frequently Asked Questions

What is the largest lake in Nebraska?

Lake McConaughy, at 30,500 acres, in Keith County. Lewis and Clark Lake is larger at 31,400 acres. It is a Missouri River reservoir shared with South Dakota, so it is not a lake lying entirely within Nebraska. Source: USACE National Inventory of Dams (Kingsley Dam, NID ID NE01048, owner Central Nebraska Public Power & Irrigation District) — corroborated by CNPPID and Nebraska Game and Parks Commission, 2026-07-30.

How is lake surface area measured?

Surface area comes from state DNR lake surveys and, for reservoirs, US Army Corps of Engineers (USACE) National Inventory of Dams records. Area is reported in acres at normal pool level. Reservoirs rise and fall with management and drought, so their listed area is the long-term normal rather than a single-day reading.

Are Nebraska's largest lakes natural or reservoirs?

Of the top 50 Nebraska lakes by area, 17 sit on a dammed river (reservoirs) and 33 are natural basins. Glacial states (MN, WI, MI, NY) skew natural; plains and southern states (MO, IA, ND, OH) skew toward reservoirs built for water supply, flood control, and recreation.

Do larger lakes have better water quality?

Not reliably. Quality varies more within a big lake than between lakes — a large lake can have a clean, deep main basin and a murky, algae-prone bay fed by a tributary, so one reading can mask wide swings. Depth, watershed land use, and how fast the lake flushes matter far more than raw surface area.

How big is the typical Nebraska lake in this ranking?

Across the top 50 Nebraska lakes by surface area, the median is 661 acres (Alkali Lake). This list is biased toward the biggest waters; the typical Nebraska lake is far smaller.

Where to stay near Nebraska's largest lakes

Planning a trip? Jump to live cabin, resort, and hotel availability near Nebraska's biggest lakes.

Deepest lakes in Nebraska →Cleanest lakes in Nebraska →Largest lakes (all states) →All Nebraska lakes →