Minnesota · Cass County
Big Deep Lake Fishing guide
Big Deep Lake covers 536 acres in Cass County, Minnesota, reaching 107 ft at its deepest point. The Minnesota DNR has surveyed the lake 3 times, most recently in 1995, with walleye, largemouth bass, smallmouth bass and northern pike in the nets. That survey is 31 years old now.
DNR survey data
Fish species
The DNR last surveyed Big Deep Lake in 1995. Ratings need a survey from the last 20 years, so this page lists the species from that older record without numbers.
- Walleye
- Largemouth bass
- Smallmouth bass
- Northern pike
- Bluegill
- Crappie
- Yellow perch
- Rock bass
How to fish Big Deep Lake through the year
Walleye
- Spring
- Walleye are shallow, on and just off the spawning flats and the first green weeds.
- Early summer
- Walleye are setting up on the outside weed edge, points and shallow structure.
- Summer
- Walleye are working the weed edge, points and any wind-blown structure. On a lake that drops to 107 ft, check the deep edge of that structure too.
- Fall
- Walleye are packing onto the sharpest breaks and points as the water cools, in big schools with short windows.
Largemouth bass
- Spring
- Largemouth are moving up into the warming bays and flats, staging around wood, docks and new weeds to spawn.
- Early summer
- Largemouth are on the shallow spawning flats and protected bays, where beds go on firm bottom next to isolated cover.
- Summer
- Largemouth are in and along the weeds: cabbage and milfoil edges, matted cover and shade. On a lake that drops to 107 ft, check the deep edge of that structure too.
- Fall
- Largemouth are chasing bait back onto the flats and into the remaining green weeds, feeding hard and shallow before the freeze.
Season patterns for each species. Open the live map for today's wind, light and water temp.
Suggested tackle
What to bring
Top presentations for this lake's structure and clarity:
Walleye · Live bait
Live-Bait (Lindy) Rig + Leech/Crawler
jumbo leech or half a nightcrawler
Walleye · Trolling
Leadcore Line + Crankbaits
4–5" mid-diving crankbait behind a long leadcore run
Largemouth bass · Hardbaits
Topwater Popper
2.5–3" concave-face popper
Largemouth bass · Hardbaits
Hollow-Body Frog
3–3.5" hollow-body frog
Smallmouth bass · Soft plastics
Drop Shot (Finesse Plastic)
4" finesse worm or 3" minnow-profile plastic
Smallmouth bass · Jigs & bladed
Tail Spinner
Compact lead body with a free-spinning blade on the tail
Full setups, including hooks, weights and line, are on the live map. As an Amazon Associate I earn from qualifying purchases.
DNR stocking records
Stocking history
| Year | Species | Stocked |
|---|---|---|
| 2022 | Walleye | 2,080 fingerlings |
| 2019 | Walleye | 2,500 fingerlings |
MN DNR · in their words
From the 1995 survey
Big Deep Lake is a 484 acre lake with a maximum depth of 107 feet. It is located six miles east of Hackensack in northern Cass County. The Minnesota Department of Natural Resources (DNR) has classified Minnesota's lakes into 43 different types, based on physical, chemical, and other characteristics. Big Deep Lake is in Lake Class 23. Other area lakes in this same class include Baby (located two miles north of Big Deep Lake), Deep Portage (located six miles northeast of Backus), Hay (located ten miles northeast of Backus), and Stony (located two miles northeast of Hackensack) Lakes. There is no public access on the lake and the only resort is on the north side of lake.An abundant northern pike population exists in Big Deep Lake. The average-size of sampled northern pike was 17.0 inches and weighed 1.3 pounds. Some northern pike larger than 28 inches were sampled. Growth was slow when compared to other area class 23 lakes.Walleye were sampled at a rate typical of other area class 23 lakes. The average-size of sampled walleye was 19 inches and weighed 2.7 pounds. It appears that some portion of the walleye population is immigrating from other lakes by way of the Boy River. Sampled walleye were growing at a good rate when compared to class 23 lakes.The bluegill that were sampled showed good quality with 19% of the sample larger than 7 inches. Quality has declined since 1972 when it was reported that 61% of the sample was larger than 7 inches. The growth rate for bluegill was slow. Six inch bluegill averaged eight years old.As in previous years, low numbers of black crappie and largemouth bass were sampled. Summer netting often does not sample these species relative to their abundance.Other fish sampled include yellow perch, pumpkinseed, rock bass, yellow bullhead, brown bullhead, black bullhead, and white sucker. Muskellunge have also been reported in Big Deep.To help maintain quality fish populations in Big Deep Lake, lake users should safeguard aquatic habitat by preserving or reestablishing aquatic plants and natural shorelines. Aquatic and terrestrial plants provide food and cover for fish and wildlife. They also help protect shorelines from erosion, and absorb nutrients and pollutants. Natural shorelines, shorelines that have not been altered by man, help protect a lake from silt-laden runoff water. They also provide excellent places for wildlife to feed, hide, and raise their young. Protection of the larger watershed that drains into Big Deep Lake is also needed for maintaining water quality.Anglers can help maintain or improve the quality fishing by practicing catch and release of medium to large-sized fish. Releasing these fish will help maintain the quality of the fish population and provide anglers with more opportunities to catch mor large fish in the future.
Narrative text from the Minnesota DNR lake survey.
Recent reports
Big Deep Lake fishing reports
Recent reports on Big Deep Lake from guides, tournaments and regular anglers. Anything posted in the last two weeks also bumps the matching spots on the live map, so you'll see a "matches a recent report" tag on them.
Public water access
Getting on the water
- Public access: NONE DEEP PORTAGE RESERVE BORDERS LAKE IN SEC 31 32.
DNR bathymetry
Big Deep Lake depth map
Within 30 miles
Nearby lakes
- Trillium Lake · 156 ac · 1.5 mi
- Long Lake · 246 ac · 2.1 mi
- Sand Lake · 41 ac · 2.1 mi
- Sand Lake · 149 ac · 2.2 mi
- Widow Lake · 198 ac · 2.5 mi
- Deep Portage Lake · 129 ac · 2.7 mi
- Kid Lake · 168 ac · 3 mi
- Island Lake · 184 ac · 3.1 mi
Quick answers
Frequently asked questions
How deep is Big Deep Lake?
Big Deep Lake reaches 107 ft at its deepest point; about 9% of the lake is littoral (15 ft or shallower).
How big is Big Deep Lake?
Big Deep Lake covers 536 acres with about 5 miles of shoreline.
What fish are in Big Deep Lake?
Minnesota DNR surveys (most recently 1995) record walleye, largemouth bass, smallmouth bass, northern pike, bluegill, crappie, yellow perch, rock bass.
Is Big Deep Lake stocked?
Yes. The DNR stocked walleye in 2022; the stocking table on this page lists every year back to 2019.
Does Big Deep Lake have a public access?
Yes. Big Deep Lake has one public access site: Public access (NONE DEEP PORTAGE RESERVE BORDERS LAKE IN SEC 31 32.).
When was Big Deep Lake last surveyed?
The Minnesota DNR last surveyed Big Deep Lake in 1995, the most recent of 3 surveys on record. That is more than 20 years ago, so this page lists species without ratings.
Page updated .
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