Blackwater Lake
Cass County, Minnesota - DNR stocking history, depth and survey data
Minnesota · Minnesota Department of Natural Resources (DNR) · DOW 11027400
DNR records show 7 stocking entries at Blackwater Lake since 2016, most recently walleye fingerlings in 2024 (3,696 fish).
- Blackwater Lake has 7 DNR stocking records across 6 years (2016-2024): walleye (7).
- The most-stocked species by count is walleye: 37,674 fish on record.
- Maximum depth 67 ft; surface area 771 acres, 336 littoral acres, 7.7 miles of shoreline, per the DNR lake survey.
- Average water clarity (Secchi depth) 12.5 ft.
- Fish species DNR lists here: black bullhead, black crappie, bluegill, bowfin (dogfish), brown bullhead, hybrid sunfish, largemouth bass, northern pike, pumpkinseed, rock bass, smallmouth bass, tullibee (cisco), and 4 more.
- 1 public access on the DNR list.
- Most recent DNR fish survey: (standard survey).
- Cass County, nearest town Longville; DNR lake number (DOW) 11027400.
Depth map
Bathymetric contours from the Minnesota DNR lake survey mapped 8/29/1958 (orig map); depths in feet. Simplified for the web; not for navigation.
Stocking history
| Year | Species | Size | Number | Pounds |
|---|---|---|---|---|
| 2024 | Walleye2 | fingerlings | 3,696 | 231.0 |
| 2024 | Walleye | fingerlings | 1,106 | 178.0 |
| 2022 | Walleye2 | fingerlings | 5,776 | 339.0 |
| 2021 | Walleye1 | yearlings | 2,688 | 672.0 |
| 2020 | Walleye | yearlings | 357 | 339.0 |
| 2018 | Walleye2 | fingerlings | 5,880 | 337.7 |
| 2016 | Walleye2 | fingerlings | 18,171 | 677.7 |
1 fish purchased and stocked by private citizens and sporting groups. 2 fish purchased by the DNR for stocking.
Field note · Minnesota stocks by year, not by truck day: walleye fry go in within weeks of ice-out, fingerlings and yearlings mostly in fall, and stream trout in spring and fall. A row here means the fish went in during that year; DNR adds the year's rows after the fact, so the current year can look empty until winter.
Public accesses
| Type | Owner | Where |
|---|---|---|
| concrete ramp | Minnesota DNR | Public access on northeast shore. |
DNR fish survey, 2023
| Species | Gear | Catch per net | Total catch | Avg lb |
|---|---|---|---|---|
| Largemouth bass | Standard electrofishing | 59.90 | 120 | 0.79 |
| Smallmouth bass | Standard electrofishing | 3.49 | 7 | 1.19 |
| Northern pike | Standard gill nets | 9.83 | 118 | 2.27 |
| Tullibee (cisco) | Standard gill nets | 3.92 | 47 | 1.84 |
| Pumpkinseed | Standard gill nets | 3.58 | 43 | 0.21 |
| Largemouth bass | Standard gill nets | 3.08 | 37 | 0.80 |
| Bluegill | Standard gill nets | 2.75 | 33 | 0.13 |
| Rock bass | Standard gill nets | 2.67 | 32 | 0.13 |
| Walleye | Standard gill nets | 2.00 | 24 | 2.58 |
| Yellow perch | Standard gill nets | 1.67 | 20 | 0.11 |
| Bluegill | Standard trap nets | 7.45 | 82 | 0.21 |
| Rock bass | Standard trap nets | 1.27 | 14 | 0.27 |
| Hybrid sunfish | Standard trap nets | 0.82 | 9 | 0.36 |
| Pumpkinseed | Standard trap nets | 0.64 | 7 | 0.20 |
| Black crappie | Standard trap nets | 0.55 | 6 | 0.12 |
| Largemouth bass | Standard trap nets | 0.36 | 4 | 0.24 |
| Bowfin (dogfish) | Standard trap nets | 0.27 | 3 | 4.26 |
| Smallmouth bass | Standard trap nets | 0.18 | 2 | 0.07 |
Catch per net (CPUE) is the DNR survey's count per gill net or trap net set; higher means more of that species were sampled, not a fishing forecast. Top species per gear shown; where we have no verified common name for a DNR code, the code itself is shown.
Blackwater Lake is a 767-acre lake with 7.6 miles of shoreline and a maximum depth of 67 feet located southwest of Longville, MN. A DNR owned public access is located on the northeast shore. The DNR has classified Minnesota's lakes into 43 different classes based on physical, chemical, and other characteristics. Blackwater Lake is in Lake Class 25; lakes in this class are characterized as Sunfish waters. Other area lakes in this class include Boy, Girl, Hand, Inguadona, Long, and Swift Lakes. Blackwater Lake possesses a highly developed shoreline. The lake is primarily managed for Largemouth Bass, Smallmouth Bass, Northern Pike, and Walleye and secondarily for Black Crappie, Bluegill, Tullibee (Cisco), and Yellow Perch. An experimental catch and release regulation for Largemouth and Smallmouth Bass implemented in 2004 was modified to a 14-20-inch protected slot limit with 1 over 20 in 2016. The regulation was removed in 2021. Largemouth and Smallmouth Bass in Blackwater Lake provide angling opportunity for quality fish of both species. Largemouth Bass are most abundant and ranged in length from 5 to 18 inches. Smallmouth Bass are present in lower numbers and fish up to 20 inches long were sampled. Northern Pike are abundant in the lake, exceeding the maximum management goal. Sampled pike ranged from 11 to 36 inches long, averaging 22 inches. Walleye abundance in the lake is low despite fingerling stocking efforts. Walleye lengths ranged from 14 to 28 inches and averaged 20 inches long. Bluegill catch rates fell below the target management range, though exceeded size goals. Black Crappie up to 13 inches were sampled. Tullibee (Cisco) have been present in the catch since initial surveying and catch rates exceeded the management goal in 2023. Yellow Perch abundance has remained low across historical surveys. Other fish species that anglers can expect to encounter in Blackwater Lake include, Brown Bullhead, Hybrid Sunfish, Pumpkinseed, Rock Bass, Bowfin, White Sucker, and Yellow Bullhead. People can have significant impacts on lakes and the fish populations they support. Harvest, lakeshore development, removal of shoreline vegetation, and introductions of invasive species can all adversely affect fish populations. Currently, Rusty Crayfish are the only aquatic invasive species (AIS) that have been identified in Blackwater Lake. AIS are moved from infested to non-infested waters by anglers, boaters, and lake shore owners and can adversely impact lakes and fish populations. To avoid spreading AIS, lake users are required to remove all aquatic plants or…
Minnesota DNR survey narrative, .
All Minnesota stockings · every Minnesota lake with a page · state CSV · this lake on DNR LakeFinder
Stocking rows, depths, accesses and survey figures are Minnesota DNR LakeFinder data as of 2026-09-02; contours are the DNR bathymetric survey. Regulations, slot limits and special rules are on the DNR page linked above, not here.
Hear when the states we cover post stockings
One email a week in season: which waters in the states we cover were stocked, straight from the state agencies' own postings. No spam, no fishing-gear ads in the mail.
Free · double opt-in · unsubscribe anytime · we store only your email.