Updated Aug 2026
Nebraska Lake Water Quality
Water quality grades for 51 of the 592 lakes we list here, across 70 counties.
Grade Distribution
All 592 Nebraska lakes in the index: 51 (8.6%) carry an A–F grade and 541 (91.4%) are not rated, because they lack enough recent nutrient or algae sampling to support a letter.
Top-Graded Nebraska Lakes
The highest water-quality grades in Nebraska — clarity, depth, and A-F grade at a glance.
Lake Map
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Where to stay near Nebraska's top-graded lakes
Cabins, resorts, and vacation rentals around Lake C W Mcconaughy and the other top-graded Nebraska lakes pinned on the map. Live availability and prices.
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Explore Nebraska Lakes
Nebraska reports, fishing & travel
Reservoirs in Nebraska
View all 52 reservoirs →52 of 592 Nebraska lakes (9%) are man-made reservoirs in the USACE National Inventory of Dams. 36 carry a High or Significant hazard rating. The oldest matched dam dates to 1895.
EPA-Impaired Lakes in Nebraska
View all 59 impaired lakes →59 of 592 Nebraska lakes (10%) are officially listed as impaired under Clean Water Act §303(d) in the most recent EPA ATTAINS reporting cycle. 6 have an approved Total Maximum Daily Load (TMDL) restoration plan.
Nebraska Fishing & Recreation
Licenses, regulations, records, and where to fish across Nebraska.
Counties
All 70 Nebraska counties, ranked by average lake water quality. Compare them against every county nationwide in the county rankings, browse the full directory of graded lakes, or pick a different state.
Top 25 Cleanest Lakes
25 lakes25 graded lakes
| # | Lake | County | Grade | Clarity | Trophic | Access |
|---|---|---|---|---|---|---|
| 1 | ALake C W Mcconaughy | Keith | A | 7.2 ft | Mesotrophic | ✓ Public |
| 2 | ASherman Reservoir | Sherman | A | 2.4 ft | Mesotrophic | ✓ Public |
| 3 | ADavis Creek Reservoir | Greeley | A | 3.9 ft | Mesotrophic | ✓ Public |
| 4 | ALake Carter P Johnson | Sioux | A | 8.3 ft | Mesotrophic | Not recorded |
| 5 | ALake Minatare | Scotts Bluff | A | 5.5 ft | Mesotrophic | ✓ Public |
| 6 | AHershey Lake | Lincoln | A | 13.6 ft | Mesotrophic | ✓ Public |
| 7 | ABridgeport Middle Lake | Morrill | A | 18.9 ft | Oligotrophic | ✓ Public |
| 8 | AHugh Butler Lake | Frontier | A | 2.8 ft | Mesotrophic | ✓ Public |
| 9 | BCalamus Reservoir | Garfield | B | 3.6 ft | Eutrophic | ✓ Public |
| 10 | BCub Creek Lake | Keya Paha | B | 4.9 ft | Eutrophic | Not recorded |
| 11 | BLake Maloney | Lincoln | B | 2.1 ft | Eutrophic | ✓ Public |
| 12 | BMerritt Reservoir | Cherry | B | 2 ft | Hypereutrophic | ✓ Public |
| 13 | BPelican Lake | Cherry | B | 1.2 ft | Hypereutrophic | ✓ Public |
| 14 | BOliver Reservoir | Kimball | B | 1.7 ft | Eutrophic | Not recorded |
| 15 | BSmith Lake | Sheridan | B | 1.7 ft | Hypereutrophic | ✓ Public |
| 16 | BChalkrock Lake | Cedar | B | 3.3 ft | Eutrophic | ✓ Public |
| 17 | BSkyview Lake | Madison | B | 6.2 ft | Eutrophic | ✓ Public |
| 18 | BLake Whitney | Dawes | B | 0.5 ft | Eutrophic | ✓ Public |
| 19 | BCrescent Lake | Garden | B | 0.8 ft | Hypereutrophic | ✓ Public |
| 20 | BGoose Lake | Holt | B | 1 ft | Hypereutrophic | ✓ Public |
| 21 | BSwanson Reservoir | Hitchcock | B | 2.6 ft | Eutrophic | ✓ Public |
| 22 | BSwan Lake | Holt | B | 1.8 ft | Hypereutrophic | Not recorded |
| 23 | CBox Butte Reservoir | Dawes | C | 5.6 ft | Mesotrophic | ✓ Public |
| 24 | CHarry Strunk Lake | Frontier | C | 2.5 ft | Eutrophic | ✓ Public |
| 25 | CPibel Lake | Wheeler | C | 2 ft | Hypereutrophic | ✓ Public |
25 Lakes Needing Attention
25 lakes25 graded lakes
| # | Lake | County | Grade | Clarity |
|---|---|---|---|---|
| 1 | FRavenna Lake E of Ravenna | Buffalo | F | No recent samples |
| 2 | FWildwood Lake | Lancaster | F | 1.7 ft |
| 3 | FBuckskin Hills Lake | Dixon | F | 2.4 ft |
| 4 | FBurchard Lake | Pawnee | F | 1.9 ft |
| 5 | FMeadowlark Lake | Seward | F | 1.8 ft |
| 6 | FHedgefield Lake | Lancaster | F | 1.6 ft |
| 7 | FGrove Lake | Antelope | F | 2.1 ft |
| 8 | FBig Indian Lake | Gage | F | 1.5 ft |
| 9 | FLiberty Cove Lake | Webster | F | 2.2 ft |
| 10 | FRockford Lake | Gage | F | 1.7 ft |
| 11 | FSummit Lake | Burt | F | 2.6 ft |
| 12 | FSwan Creek Lake | Saline | F | 1.5 ft |
| 13 | FWillow Creek Reservoir | Sarpy | F | 1.5 ft |
| 14 | FLone Star Reservoir | Fillmore | F | 2.1 ft |
| 15 | FMaskenthine Reservoir | Stanton | F | 2.1 ft |
| 16 | DOxbow Trails Reservoir | Butler | D | 1.3 ft |
| 17 | DLake Ogallala | Keith | D | 4.9 ft |
| 18 | DPrairie Queen Lake | Sarpy | D | 3.3 ft |
| 19 | DPowder Creek Lake | Dixon | D | 2.7 ft |
| 20 | DLake Wanahoo | Saunders | D | 2.4 ft |
| 21 | DJenny Newman Lake | Cass | D | 5.4 ft |
| 22 | DHarlan County Reservoir | Harlan | D | 2.8 ft |
| 23 | DJohnson Lake | Gosper | D | 2.8 ft |
| 24 | DEnders Reservoir | Chase | D | 2.8 ft |
| 25 | DKirkman'S Cove Lake | Richardson | D | 1.4 ft |
Nebraska lists 592 lakes across 70 counties, 51 of which carry a grade. Most of the input behind those grades flows through monitoring run by the Nebraska Department of Environment and Energy, which feeds state, federal, and volunteer measurements into the EPA Water Quality Portal. The remainder are here because they are real named lakes, not because anyone has sampled them recently. About 16% of graded Nebraska lakes earn an A. The bulk sit in the middle B to C range; 49% fall into D or F, almost all of those in counties where row-crop agriculture dominates the watershed.
Lake Ogallala is the largest lake in this index at about 30,500 acres, one of 37 here that clear 500 acres. The rest run smaller, and small and shallow is where nutrient loading shows up first, because there is less water to dilute it and the bottom sediment stays within reach of the sun. A meaningful share of the state's graded lakes register as hypereutrophic: heavily nutrient-loaded, frequent blooms, low summer transparency. These are usually shallow, surrounded by row-crop agriculture, with little volume to buffer the inputs. The cleanest county on average is Sherman (grade A); the most-stressed is Buffalo. The gap between the top and bottom counties is large enough that a single figure for Nebraska lake water quality hides real local variation.
Lake Match
Which lake suits how you actually use one?
Six questions — swimming, fishing, quiet, cabins, drive time — and a shortlist of graded lakes that fit, with the water quality behind each one.
Source: EPA National Aquatic Resource Surveys and the EPA Water Quality Portal.
More on lake water quality
A data snapshot of the lakes we grade: how the A–F distribution breaks down, the clearest and the greenest states, and where the water is improving.
How lakes are graded A–F on nutrients and algae using EPA ecoregion condition classes, what each letter means in the water, and why an A is not a clearance.
The cleanest and dirtiest U.S. lakes in the monitoring record, ranked on EPA nutrient and algae condition classes across thousands of graded lakes.
The clearest lakes in America, ranked by measured Secchi depth in feet from EPA monitoring data — and why the famously clear lakes are missing.