Lake depth chart
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Rating depth structure for largemouth bass.
Shared by DepthScout anglers. Exact spots stay private, always.
307-acre reservoir in Wisconsin. The lake tops out around 21 ft. These contours are modeled — built from the real shoreline and the water's maximum depth — so read them as a guide, never as navigation. What the data behind the map says about each species, season by season:
Drawn out, this is 307 acres of water rimmed by 7.2 miles of bank, broken up by an island. An index of 2.9 puts the bank firmly in maze territory: point after pocket after cove, every one a casting target. Littoral water — the productive band under ~15 ft — makes up 83% of this chart, as modeled. End to end it runs roughly 2.1 mi, about 0.8 mi across. The water lies in Menominee County. The nearest mapped water is Lake Mary, 7 mi to the northwest.
Early season walleye use the shallows, holding in 4 to 15 ft. Summer is a 6 to 21 ft game here, winter a 6 to 21 ft one. The chart's best answer is Break off the point — drop-off, 9 ft, prime for fall. Best bite is the evening and early morning. Tie on a crawler harness on bottom bouncer or a deep crankbait (trolled) and you're in the game.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 4 to 15 ft | dusk & dawn | Main-lake point (8 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 6 to 21 ft | dusk & dawn | Break off the point (9 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 6 to 21 ft | dusk & night | Break off the point (9 ft) | Jigging rap, Jig + big minnow |
| Winter | 6 to 21 ft | dusk & dawn | Deep basin (18 ft) | Jigging spoon + minnow head, Rattle bait |
Spring yellow perch on Grand Rapids Flowage hold shallow, usually 3 to 12 ft. By summer they slide out to 6 to 21 ft, and by winter most fish are in 6 to 21 ft. The chart's best answer is Shallow bay flat — weed flat, 3 ft, prime for spring. Prime time lands in early morning. The summer box starts with a drop-shot micro plastics or a small spoon tipped with worm.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | midday & dawn | Shallow bay flat (3 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 6 to 21 ft | dawn | Deep basin (18 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 6 to 21 ft | midday | Deep basin (18 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 6 to 21 ft | midday & dawn | Deep basin (18 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Spring puts northern pike in skinny water — 2 to 8 ft is the zone. As the season builds they drop to 8 to 20 ft, wintering in 5 to 15 ft. Spring northern pike concentrate at Shallow bay flat, a prime-rated weed flat around 3 ft. Warm-month bites cluster around early morning and the evening. A bucktail or a weedless spoon over cabbage covers the summer program.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 8 ft | midday & dawn | Shallow bay flat (3 ft) | #5 inline spinner, Spoon (red/white) |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (9 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Break off the point (9 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Shallow bay flat (3 ft) | Tip-ups, Large jigging spoon |
Spring puts smallmouth bass in skinny water — 3 to 12 ft is the zone. As the season builds they drop to 6 to 21 ft, wintering in 6 to 21 ft. Fall smallmouth bass concentrate at Main-lake point, a prime-rated point around 8 ft. Warm-month bites cluster around early morning and the evening. A drop shot (goby/minnow) or a ned rig covers the summer program.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dawn & dusk | Main-lake point (8 ft) | Ned rig, Tube jig |
| Summer | 6 to 21 ft | dawn & dusk | Break off the point (9 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 6 to 21 ft | midday & dawn | Main-lake point (8 ft) | Jerkbait, Blade bait |
| Winter | 6 to 21 ft | midday | Break off the point (9 ft) | Blade bait, Hair jig |
In spring, largemouth bass run shallow here, mostly 2 to 10 ft. Summer pushes them deeper, 8 to 20 ft, and winter fish settle into 6 to 21 ft. Shallow bay flat is the standout, a weed flat at roughly 3 ft, rated prime for spring largemouth bass. Time it for early morning and the evening. You won't need more than a texas-rigged 10" worm or a deep-diving crankbait most summer days.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 10 ft | dawn & dusk | Shallow bay flat (3 ft) | Spinnerbait, Chatterbait |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (9 ft) | Texas-rigged 10" worm, Deep-diving crankbait |
| Fall | 4 to 15 ft | midday & dawn | Main-lake point (8 ft) | Squarebill crankbait (shad), Spinnerbait |
| Winter | 6 to 21 ft | midday | Break off the point (9 ft) | Blade bait, Jigging spoon |
Spring puts crappie in skinny water — 2 to 8 ft is the zone. As the season builds they drop to 6 to 21 ft, wintering in 6 to 21 ft. Winter crappie concentrate at Deep basin, a prime-rated deep basin around 18 ft. Warm-month bites cluster around early morning and the evening. A jig trolled/spider-rigged or a small crankbait (trolled) covers the summer program.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 8 ft | midday & dawn | Shallow bay flat (3 ft) | 1/16 oz jig + tube, Curly-tail grub |
| Summer | 6 to 21 ft | dawn & dusk | Break off the point (9 ft) | Jig trolled/spider-rigged, Small crankbait (trolled) |
| Fall | 8 to 20 ft | dawn | Break off the point (9 ft) | Jig + minnow combo, Small swimbait (1.5-2") |
| Winter | 6 to 21 ft | midday | Deep basin (18 ft) | Tungsten jig + soft plastic, Tiny jigging spoon |
Grand Rapids Flowage also holds bluegill (4 to 15 ft in summer), pumpkinseed (2 to 10 ft in summer). Pick any of them on the map above for rated spots and bait picks.
Count 6 structure marks on this chart. The deepest, Deep basin, sits near 18 ft.
Access data: Wisconsin DNR - Boat Access Sites, Shore Fishing Sites, and DNR Parking Lots. Confirm conditions and fees locally before you launch.
| Date | Species | Count | Size |
|---|---|---|---|
| 2025* | Black Crappie (large fingerling) | 497 | ~6" |
| 2025* | Yellow Perch (large fingerling) | 1,000 | ~7" |
| 2024* | Yellow Perch (large fingerling) | 1,000 | ~6" |
| 2024* | Black Crappie (large fingerling) | 500 | ~4" |
* Approximate date (agency reports month or season only). Source: Wisconsin DNR fish-stocking summary, retrieved 2026-08-18.
Season dates, license requirements, and size and bag limits for Wisconsin waters are set by the Wisconsin DNR — and special regulations can apply to Grand Rapids Flowage specifically, so confirm the current rules before you fish.
Check the official Wisconsin fishing regulations →
Grand Rapids Flowage is about 21 ft (6 m) deep at its deepest point. The contours here are modeled from the water's real shape and maximum depth, so treat them as a rough guide.
Anglers target walleye, yellow perch, northern pike, smallmouth bass, largemouth bass, crappie, bluegill, pumpkinseed on Grand Rapids Flowage. These come from the Wisconsin DNR's per-lake fish listing; where the DNR lists a group (panfish, catfish, trout) the specific species are resolved from Wisconsin's fish distribution by the lake's location, depth and habitat.
Break off the point is the top-rated area: a drop-off in about 9 ft of water that rates prime for walleye in fall. The interactive chart above rates every spot for each species and season.
For walleye, the summer bite is best in the evening and early morning. Each species page section below lists the seasonal windows, and the map shows a live NOW badge when you're inside one.
Yes — per Wisconsin DNR fish-stocking summary records, Grand Rapids Flowage was most recently stocked 2025 with 497 black crappie (large fingerling). The full stocking history is listed above.
Fishing on Grand Rapids Flowage is regulated by the Wisconsin DNR. Check the official Wisconsin regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.
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See how Grand Rapids Flowage stacks up: best largemouth bass lakes in Wisconsin · best smallmouth bass lakes in Wisconsin · best walleye lakes in Wisconsin · best northern pike lakes in Wisconsin
More water nearby: Menominee County fishing maps (8 charts). Browse all Wisconsin fishing maps or see every water on DepthScout. How we build these maps. Fish here with a sonar unit that logs? Send us your depth data and we'll improve this chart, credited to you. For fishing guidance only, never navigation.