Lake depth chart
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Shared by DepthScout anglers. Exact spots stay private, always.
253-acre lake in Ontario. The lake tops out around 40 ft. The contours come from a model of the real basin shape and its known max depth. Read them as probabilities, not soundings, and keep them out of navigation decisions. Every species below gets its seasonal read from the same numbers driving the chart.
On the chart, Rathbun Lake draws 253 acres inside 6.6 miles of shoreline. An index of 3 puts the bank firmly in maze territory: point after pocket after cove, every one a casting target. About 78% of the surface sits shallower than 15 ft on the modeled chart — that's the weed-and-bait zone. Tip to tip the water measures near 2.2 mi with a 0.5-mi widest point. The water lies in Greater Sudbury / Grand Sudbury. Closest neighbour on DepthScout: Poulton Lake, 1 mi southeast of here.
When the water first warms, lake whitefish slide up into 12 to 40 ft. There's no big seasonal slide here — summer means 12 to 40 ft, winter 12 to 40 ft. If you only fish one area, make it Deep basin: a deep basin around 34 ft that scores prime in summer. In summer the feeding windows fall in early morning. Keep a blade bait vertical or a small jigging spoon rigged through the warm months.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 12 to 40 ft | midday & dawn | Break off the point (18 ft) | Small jig + waxworm, Blade bait (small) |
| Summer | 12 to 40 ft | dawn | Deep basin (34 ft) | Blade bait vertical, Small jigging spoon |
| Fall | 8 to 30 ft | dusk | Break off the point (18 ft) | Small spoon (gold), Jig + plastic larva |
| Winter | 12 to 40 ft | midday & dawn | Deep basin (34 ft) | Jigging spoon + bead chain, Tungsten jig + waxie |
Early season walleye use the shallows, holding in 4 to 15 ft. Summer is a 15 to 35 ft game here, winter a 20 to 40 ft one. The chart's best answer is Break off the point — drop-off, 18 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 (10 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 15 to 35 ft | dusk & dawn | Break off the point (18 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 12 to 40 ft | dusk & night | Break off the point (18 ft) | Jigging rap, Jig + big minnow |
| Winter | 20 to 40 ft | dusk & dawn | Deep basin (34 ft) | Jigging spoon + minnow head, Rattle bait |
Spring yellow perch on Rathbun Lake hold shallow, usually 3 to 12 ft. By summer they slide out to 10 to 30 ft, and by winter most fish are in 15 to 35 ft. The chart's best answer is Shallow bay flat — weed flat, 5 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 (5 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 10 to 30 ft | dawn | Break off the point (18 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 12 to 35 ft | midday | Deep basin (34 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 15 to 35 ft | midday & dawn | Deep basin (34 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 5 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 (5 ft) | #5 inline spinner, Spoon (red/white) |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (18 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Break off the point (18 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Shallow bay flat (5 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 10 to 30 ft, wintering in 12 to 40 ft. Fall smallmouth bass concentrate at Main-lake point, a prime-rated point around 10 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 (10 ft) | Ned rig, Tube jig |
| Summer | 10 to 30 ft | dawn & dusk | Break off the point (18 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 8 to 25 ft | midday & dawn | Main-lake point (10 ft) | Jerkbait, Blade bait |
| Winter | 12 to 40 ft | midday | Break off the point (18 ft) | Blade bait, Hair jig |
When the water first warms, rock bass slide up into 2 to 10 ft. By summer they slide out to 5 to 20 ft, and by winter most fish are in 12 to 30 ft. If you only fish one area, make it Main-lake point: a point around 10 ft that scores prime in summer. In summer the feeding windows fall in the evening. Keep a ned rig (small) or a marabou jig rigged through the warm months.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 10 ft | midday & dawn | Main-lake point (10 ft) | 1/16 oz jig + grub, Small inline spinner |
| Summer | 5 to 20 ft | dusk | Main-lake point (10 ft) | Ned rig (small), Marabou jig |
| Fall | 8 to 22 ft | midday | Break off the point (18 ft) | Small tube jig, Inline spinner |
| Winter | 12 to 30 ft | midday | Break off the point (18 ft) | Tungsten jig + plastic, Small spoon + spike |
The chart marks 6 structure features on Rathbun Lake; the deepest is Deep basin at about 34 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 Rathbun Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Rathbun Lake is about 40 ft (12 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 lake whitefish, walleye, yellow perch, northern pike, smallmouth bass, rock bass on Rathbun Lake.
Deep basin is the top-rated area: a deep basin in about 34 ft of water that rates prime for lake whitefish in summer. The map above holds the full rated-spot list for every 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 Rathbun 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.
Poulton Lake 1 mi · Boland's Lake 3 mi · Matagamasi Lake 4 mi · Portage Lake 5 mi · Lake Wanapitei 5 mi · Kukagami Lake 6 mi · Caswell Lake 6 mi · L. 27 6 mi · Kettyle Lake 6 mi · Dewdney Lake 7 mi · Donald Lake 7 mi · Irish Lake 8 mi
See how Rathbun Lake stacks up: best smallmouth bass lakes in Ontario · best walleye lakes in Ontario · best northern pike lakes in Ontario · best yellow perch lakes in Ontario
More water nearby: Greater Sudbury / Grand Sudbury fishing maps (88 charts). Browse all Ontario 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.