Sign inSign up free Sign inSign up free Sign inSign up freeLake depth chart
Today's read
Recent public catches load as you reach this section.
1,123-acre lake in Timiskaming 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. Species by species, here's what the data says the year looks like.
Drawn out, this is 1,126 acres of water rimmed by 12.8 miles of bank, with 3 islands in the mix. With a shoreline index of 2.7, this water is all arms and coves — edge habitat well beyond its acreage. 96% of the surface is littoral (under ~15 ft), per the model — cover, weeds and forage water. Tip to tip the water measures near 3.6 mi with a 1.1-mi widest point. The water lies in Timiskaming District. The nearest mapped water is Serpentine Lake, 1 mi to the northeast.
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 Firth 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, lake whitefish slide up into 6 to 20 ft. There's no big seasonal slide here — summer means 6 to 20 ft, winter 6 to 20 ft. If you only fish one area, make it Deep basin: a deep basin around 17 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.
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 | 6 to 20 ft chart-limited; documented 15 to 45 ft | midday & dawn | Break off the point (9 ft) | Small jig + waxworm, Blade bait (small) |
| Summer | 6 to 20 ft chart-limited; documented 40 to 90 ft | dawn | Deep basin (17 ft) | Blade bait vertical, Small jigging spoon |
| Fall | 5 to 20 ft chart-limited; documented 8 to 30 ft | dusk | Break off the point (9 ft) | Small spoon (gold), Jig + plastic larva |
| Winter | 6 to 20 ft chart-limited; documented 25 to 70 ft | midday & dawn | Deep basin (17 ft) | Jigging spoon + bead chain, Tungsten jig + waxie |
Count 6 structure marks on this chart. The deepest, Deep basin, sits near 17 ft.
Access data: Geospatial Ontario - Fishing Access Points; Government of Ontario - MNR Unpatented Crown Land Shoreline; Government of Ontario - MNR Unpatented Crown Land Shoreline. 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 Firth Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Firth 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, lake whitefish on Firth 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. Open the map above to see every rated 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.
Fishing on Firth 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.
Serpentine Lake 1 mi · Lett Lake 2 mi · North Gamble Lake 2 mi · Gorman Lake 2 mi · Logan Lake 3 mi · Diabase Lake 3 mi · Metikemedo L. 3 mi · Margueratt Lake 4 mi · Milner L. 4 mi · Edith Lake 4 mi · Burk Lake 4 mi · Boyd L. 4 mi
See how Firth 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: Timiskaming District fishing maps (515 charts). Browse all Ontario fishing maps. See every water on DepthScout. Shoreline: OpenStreetMap contributors (ODbL). This is a shoreline guide. Modeled depth contours have been retired. 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.