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275-acre lake in Algoma District, Ontario. The lake tops out around 70 ft. The depth chart comes from Ontario Ministry of Natural Resources and Forestry bathymetric survey data, so the contours are survey-derived rather than computer-modeled. The depth data here comes from the Ontario MNRF survey of 1975, a decades-old survey (a transect sounding survey). The season-by-season read for each species follows, from the map's own numbers.
Grandeur Lake maps at 276 acres behind 6.1 miles of shoreline — 3 islands included. An index of 2.6 puts the bank firmly in maze territory: point after pocket after cove, every one a casting target. The shallow band under 15 ft claims about 33% of the surface — that's where the groceries are. Call it 1.4 mi long by 0.6 mi wide at the broadest reach. It sits in Algoma District. Marshland Lake sits 1 mi west — the closest neighbouring chart.
These fish are listed in an exact-water agency record as forage or ecological context. They are not target-species profiles and do not affect DepthScout's Prime, Good, or Fair spot ratings.
Official Ontario MNRF Fish ON-Line record. The listing documents source-recorded presence, not present abundance or guaranteed catchability.
Start shallow in spring: lake whitefish sit in 15 to 45 ft that time of year. Summer pushes them deeper, 21 to 70 ft, and winter fish settle into 25 to 70 ft. The spot to know is Deep basin, a deep basin in about 70 ft of water that rates prime for lake whitefish in summer. Warm-month bites cluster around early morning. Throw a blade bait vertical or a small jigging spoon until the fish tell you otherwise.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 15 to 45 ft | midday & dawn | Break off the point (40 ft) | Small jig + waxworm, Blade bait (small) |
| Summer | 21 to 70 ft chart-limited; documented 40 to 90 ft | dawn | Deep basin (70 ft) | Blade bait vertical, Small jigging spoon |
| Fall | 8 to 30 ft | dusk | open water | Small spoon (gold), Jig + plastic larva |
| Winter | 25 to 70 ft | midday & dawn | Deep basin (70 ft) | Jigging spoon + bead chain, Tungsten jig + waxie |
Start shallow in spring: cisco (lake herring) sit in 10 to 40 ft that time of year. Summer pushes them deeper, 21 to 70 ft, and winter fish settle into 20 to 60 ft. The spot to know is Deep basin, a deep basin in about 70 ft of water that rates prime for cisco (lake herring) in summer. Warm-month bites cluster around early morning. Throw a vertical flutter spoon (small) or a drop-shot micro plastic until the fish tell you otherwise.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 10 to 40 ft | dawn & dusk | Break off the point (40 ft) | Small silver spoon, Tiny swim jig (white) |
| Summer | 21 to 70 ft chart-limited; documented 40 to 80 ft | dawn | Deep basin (70 ft) | Vertical flutter spoon (small), Drop-shot micro plastic |
| Fall | 5 to 25 ft | dusk & dawn | open water | Small casting spoon, Inline spinner (silver) |
| Winter | 20 to 60 ft | dawn | Deep basin (70 ft) | Small jigging spoon (glow/silver), Tungsten jig + minnow head |
When the water first warms, smallmouth bass slide up into 3 to 12 ft. Summer is a 10 to 30 ft game here, winter a 20 to 45 ft one. Start at Break off the point. It's a drop-off holding about 40 ft of water and rates prime come winter. The feeding windows run early morning and the evening. Keep a drop shot (goby/minnow) or a ned rig rigged through the warm months.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dawn & dusk | Main-lake point (1 ft) | Ned rig, Tube jig |
| Summer | 10 to 30 ft | dawn & dusk | Main-lake point (1 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 8 to 25 ft | midday & dawn | Main-lake point (1 ft) | Jerkbait, Blade bait |
| Winter | 20 to 45 ft | midday | Break off the point (40 ft) | Blade bait, Hair jig |
Start shallow in spring: rock bass sit in 2 to 10 ft that time of year. Summer pushes them deeper, 5 to 20 ft, and winter fish settle into 12 to 30 ft. The spot to know is Main-lake point, a point in about 1 ft of water that rates good for rock bass in summer. Warm-month bites cluster around the evening. Throw a ned rig (small) or a marabou jig until the fish tell you otherwise.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 10 ft | midday & dawn | Main-lake point (1 ft) | 1/16 oz jig + grub, Small inline spinner |
| Summer | 5 to 20 ft | dusk | Main-lake point (1 ft) | Ned rig (small), Marabou jig |
| Fall | 8 to 22 ft | midday | open water | Small tube jig, Inline spinner |
| Winter | 12 to 30 ft | midday | open water | Tungsten jig + plastic, Small spoon + spike |
When the water first warms, burbot slide up into 25 to 70 ft. There's no big seasonal slide here — summer means 21 to 70 ft, winter 15 to 60 ft. If you only fish one area, make it Deep basin: a deep basin around 70 ft that scores prime in spring. In summer the feeding windows fall in after dark and midday. Keep a heavy jig + cut bait rigged through the warm months.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 25 to 70 ft | night & dusk | Deep basin (70 ft) | Glow jigging spoon + cut bait, Rattle bait (dark) |
| Summer | 21 to 70 ft chart-limited; documented 50 to 120 ft | night & midday | Deep basin (70 ft) | Heavy jig + cut bait |
| Fall | 21 to 70 ft chart-limited; documented 30 to 80 ft | night & dusk | Deep basin (70 ft) | Glow spoon + minnow head, Blade bait (slow) |
| Winter | 15 to 60 ft | night & dusk | Break off the point (40 ft) | Glow tungsten + cut bait, Rattle spoon + minnow head |
Come spring, look for rainbow smelt tight to the bank in 2 to 20 ft. They move out to 21 to 70 ft in summer and finish the year down in 15 to 60 ft. If you only fish one area, make it Deep basin: a deep basin around 70 ft that scores prime in summer. Best bite is early morning and the evening. A tiny vertical jig or a small sabiki-style rig where legal is the honest summer answer here.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 20 ft | night & dusk | Shallow feeding flat (20 ft) | Tiny silver jig, Micro spoon |
| Summer | 21 to 70 ft chart-limited; documented 25 to 80 ft | dawn & dusk | Deep basin (70 ft) | Tiny vertical jig, Small sabiki-style rig where legal |
| Fall | 18 to 65 ft | dusk & dawn | Deep basin (70 ft) | Micro spoon, Tiny jig |
| Winter | 15 to 60 ft | dusk | Deep basin (70 ft) | Tiny glow jig, Micro jigging spoon |
The chart marks 7 structure features on Grandeur Lake; the deepest is Deep basin at about 70 ft.
Season dates, license requirements, and size and bag limits for Ontario waters are set by the Ontario fishing regulations (FMZ summary) — and special regulations can apply to Grandeur Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Grandeur Lake is about 70 ft (21 m) deep at its deepest point. The depth data here comes from the Ontario MNRF survey of 1975, a decades-old survey (a transect sounding survey).
Anglers target lake whitefish, cisco (lake herring), smallmouth bass, rock bass, burbot, rainbow smelt on Grandeur Lake.
Deep basin is the top-rated area: a deep basin in about 70 ft of water that rates prime for lake whitefish in summer. Scroll up to the map for the complete spot list by species and season.
For lake whitefish, the summer bite is best in early morning. Each species page section below lists the seasonal windows, and the map shows a live NOW badge when you're inside one.
Fishing on Grandeur Lake is regulated by the Ontario fishing regulations (FMZ summary). Check the official Ontario regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.
Marshland Lake 1 mi · Belle Lake 1 mi · Christie Lake 1 mi · Spur Lake 2 mi · Proctor Lake 3 3 mi · Ivans L. 3 mi · Nordic Lake 3 mi · Esten Lake 4 mi · Turtle Lake 4 mi · Porridge Lake 4 mi · Ryan Lake 4 mi · First Lake 4 mi
See how Grandeur Lake stacks up: best smallmouth bass lakes in Ontario · best lake whitefish lakes in Ontario · best burbot lakes in Ontario · best rock bass lakes in Ontario
More water nearby: Algoma District fishing maps (1026 charts). Browse all Ontario fishing maps. See every water on DepthScout. Bathymetry: published agency survey data. 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.