Lake depth chart
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1,408-acre lake in Rainy River District, Ontario. The lake tops out around 20 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. Here is how the season plays out for each species, straight from the data behind the map.
On the chart, Big Sawbill Lake draws 1,409 acres inside 11.3 miles of shoreline — one island included. Index 2.1 on the shoreline: a few honest points and pockets, nothing labyrinthine. The shallow band under 15 ft claims about 90% of the surface on the model — that's where the groceries are. Tip to tip the water measures near 3.9 mi with a 1.2-mi widest point. The water lies in Rainy River District. Closest neighbour on DepthScout: Tupman Lake, 3 mi northwest of here.
Early season walleye use the shallows, holding in 4 to 15 ft. Summer is a 6 to 20 ft game here, winter a 6 to 20 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.
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 | 4 to 15 ft | dusk & dawn | Main-lake point (8 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 6 to 20 ft chart-limited; documented 15 to 35 ft | dusk & dawn | Break off the point (9 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 6 to 20 ft chart-limited; documented 12 to 40 ft | dusk & night | Break off the point (9 ft) | Jigging rap, Jig + big minnow |
| Winter | 6 to 20 ft chart-limited; documented 20 to 40 ft | dusk & dawn | Deep basin (17 ft) | Jigging spoon + minnow head, Rattle bait |
Spring yellow perch on Big Sawbill Lake hold shallow, usually 3 to 12 ft. By summer they slide out to 6 to 20 ft, and by winter most fish are in 6 to 20 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.
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 | 3 to 12 ft | midday & dawn | Shallow bay flat (3 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 6 to 20 ft chart-limited; documented 10 to 30 ft | dawn | Deep basin (17 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 6 to 20 ft chart-limited; documented 12 to 35 ft | midday | Deep basin (17 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 6 to 20 ft chart-limited; documented 15 to 35 ft | midday & dawn | Deep basin (17 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 20 ft, wintering in 6 to 20 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.
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 | 3 to 12 ft | dawn & dusk | Main-lake point (8 ft) | Ned rig, Tube jig |
| Summer | 6 to 20 ft chart-limited; documented 10 to 30 ft | dawn & dusk | Break off the point (9 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 6 to 20 ft chart-limited; documented 8 to 25 ft | midday & dawn | Main-lake point (8 ft) | Jerkbait, Blade bait |
| Winter | 6 to 20 ft chart-limited; documented 20 to 45 ft | midday | Break off the point (9 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 6 to 20 ft. If you only fish one area, make it Main-lake point: a point around 8 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.
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 10 ft | midday & dawn | Main-lake point (8 ft) | 1/16 oz jig + grub, Small inline spinner |
| Summer | 5 to 20 ft | dusk | Main-lake point (8 ft) | Ned rig (small), Marabou jig |
| Fall | 6 to 20 ft chart-limited; documented 8 to 22 ft | midday | Break off the point (9 ft) | Small tube jig, Inline spinner |
| Winter | 6 to 20 ft chart-limited; documented 12 to 30 ft | midday | Deep basin (17 ft) | Tungsten jig + plastic, Small spoon + spike |
Spring puts crappie in skinny water — 2 to 8 ft is the zone. As the season builds they drop to 6 to 20 ft, wintering in 6 to 20 ft. Winter crappie concentrate at Deep basin, a prime-rated deep basin around 17 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.
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 8 ft | midday & dawn | Shallow bay flat (3 ft) | 1/16 oz jig + tube, Curly-tail grub |
| Summer | 6 to 20 ft chart-limited; documented 10 to 25 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 20 ft chart-limited; documented 15 to 35 ft | midday | Deep basin (17 ft) | Tungsten jig + soft plastic, Tiny jigging spoon |
Big Sawbill Lake also holds 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 17 ft.
Access data: Geospatial Ontario - Fishing Access Points. Confirm conditions and fees locally before you launch.
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 Big Sawbill Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Big Sawbill Lake is about 20 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, rock bass, crappie, pumpkinseed on Big Sawbill Lake.
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 map above holds the full rated-spot list for every 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.
Fishing on Big Sawbill 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.
Tupman Lake 3 mi · Cherry Lake 4 mi · Ryckman Lake 4 mi · Marsh Lake 5 mi · Cuttle Lake 5 mi · Grimshaw Lake 6 mi · Doman Lake 6 mi · Weller Lake 6 mi · Otukamamoan Lake 7 mi · Poulson Lake 7 mi · Winkle Lake 7 mi · Obikoba Lake 8 mi
See how Big Sawbill Lake stacks up: best smallmouth bass lakes in Ontario · best walleye lakes in Ontario · best northern pike lakes in Ontario · best crappie lakes in Ontario
More water nearby: Rainy River District fishing maps (257 charts). Browse all Ontario fishing maps. 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.