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Rating depth structure for lake trout.
Recent public catches load as you reach this section.
486-acre lake near Brûlé. The lake tops out around 90 ft. The depth chart comes from Alberta Geological Survey bathymetric survey data, so the contours are survey-derived rather than computer-modeled. Every species below gets its seasonal read from the same numbers driving the chart.
Drawn out, this is 485 acres of water rimmed by 5.6 miles of bank. The shoreline is moderately structured (index 1.8) — enough points and pockets to pattern. 35% of the surface is littoral (under ~15 ft) — cover, weeds and forage water. The basin spans about 2.1 mi end to end and 0.8 mi across at its widest. The water lies in Division No. 14. The nearest mapped water is Jarvis Lake, 19 mi to the east.
In spring, lake trout run shallow here, mostly 10 to 40 ft. Summer pushes them deeper, 27 to 90 ft, and winter fish settle into 20 to 80 ft. Deep basin is the standout, a deep basin at roughly 90 ft, rated prime for summer lake trout. Time it for early morning. You won't need more than a white tube jig (deep) or a magnum spoon on downrigger most summer days.
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) | Casting spoon over shoals, Jerkbait (shallow) |
| Summer | 27 to 90 ft chart-limited; documented 50 to 120 ft | dawn | Deep basin (90 ft) | White tube jig (deep), Magnum spoon on downrigger |
| Fall | 10 to 50 ft | dusk & dawn | Break off the point (40 ft) | Heavy casting spoon, Jigging rap over reefs |
| Winter | 20 to 80 ft | dawn | Break off the point (40 ft) | White tube jig, Airplane jig |
Spring lake whitefish on Rock Lake hold shallow, usually 15 to 45 ft. By summer they slide out to 40 to 90 ft, and by winter most fish are in 25 to 70 ft. The chart's best answer is Deep basin — deep basin, 90 ft, prime for summer. Prime time lands in early morning. The summer box starts with a blade bait vertical or a small jigging spoon.
| 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 | 40 to 90 ft | dawn | Deep basin (90 ft) | Blade bait vertical, Small jigging spoon |
| Fall | 8 to 30 ft | dusk | Main-lake point (3 ft) | Small spoon (gold), Jig + plastic larva |
| Winter | 25 to 70 ft | midday & dawn | Break off the point (40 ft) | Jigging spoon + bead chain, Tungsten jig + waxie |
The spring pattern is a shallow one: northern pike in 2 to 8 ft. As the season builds they drop to 8 to 20 ft, wintering in 5 to 15 ft. Top water on the chart: Shallow bay flat, a weed flat in the 6 ft range, prime in spring. Time it for early morning and the evening. Summer baits: a bucktail or a weedless spoon over cabbage gets it done.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 8 ft | midday & dawn | Shallow bay flat (6 ft) | #5 inline spinner, Spoon (red/white) |
| Summer | 8 to 20 ft | dawn & dusk | Shallow feeding flat 1 (13 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Shallow bay flat (6 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Shallow bay flat (6 ft) | Tip-ups, Large jigging spoon |
Spring puts bull trout in skinny water — 10 to 40 ft is the zone. As the season builds they drop to 30 to 90 ft, wintering in 20 to 70 ft. Summer bull trout concentrate at Deep basin, a prime-rated deep basin around 90 ft. Warm-month bites cluster around early morning and the evening. A trolled plug on downrigger or a heavy jigging spoon covers the summer program.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 10 to 40 ft | dawn & dusk | Break off the point (40 ft) | Large jointed plug, 6" swimbait (kokanee/trout pattern) |
| Summer | 30 to 90 ft | dawn & dusk | Deep basin (90 ft) | Trolled plug on downrigger, Heavy jigging spoon |
| Fall | 5 to 35 ft | dawn & dusk | Main-lake point (3 ft) | Large glide bait, Jointed plug |
| Winter | 20 to 70 ft | dawn | Break off the point (40 ft) | Heavy spoon (slow lift), Large soft swimbait |
Count 8 structure marks on this chart. The deepest, Deep basin, sits near 90 ft.
Season dates, license requirements, and size and bag limits for Alberta waters are set by the Alberta fishing regulations — and special regulations can apply to Rock Lake specifically, so confirm the current rules before you fish.
Check the official Alberta fishing regulations →
Rock Lake is about 90 ft (27 m) deep at its deepest point. The depth chart comes from Alberta Geological Survey bathymetric survey data, so the contours are survey-derived rather than computer-modeled.
Anglers target lake trout, lake whitefish, northern pike, bull trout on Rock Lake.
Deep basin is the top-rated area: a deep basin in about 90 ft of water that rates prime for lake trout in summer. The map above holds the full rated-spot list for every species and season.
For lake trout, 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 Rock Lake is regulated by the Alberta fishing regulations. Check the official Alberta regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.
Jarvis Lake 19 mi · Graveyard/Cache Lakes 19 mi · Gregg Lake 20 mi · Kinky Lake 23 mi · Wildhorse Lakes 23 mi · Pierre Greys Lakes 34 mi · Portal Lake 40 mi, BC/AB · Mary Gregg Lake 41 mi · Yellowhead Lake 43 mi, BC · Witney Lake 43 mi, BC · Moose Lake 44 mi, BC · Grande Cache Lake 44 mi
See how Rock Lake stacks up: best northern pike lakes in Alberta · best lake trout lakes in Alberta · best lake whitefish lakes in Alberta
More water nearby: Division No. 14 fishing maps (13 charts). Browse all Alberta fishing maps. See every water on DepthScout. Depth data: Alberta Geological Survey, Lake bathymetry. 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.