Coopers Lake Depth Map & Fishing Spots (MT)

Hatch outlook

Grasshoppers (east-side summer)Active window

Typical here: Jul 1 – Oct 15 · until the hard frosts of mid-October; on the Missouri, August hoppers fish mid-river, not the banks

adultall day in high summer, best when afternoon wind knocks bugs onto the water

Pulls fish to the windward grassy banks and edges for months — fish the bank the wind blows ONTO.

The friendliest crossover of the summer: on lakes, drift the windward bank with a bubble-and-foam-hopper — the bubble's splash doesn't hurt a hopper presentation. On rivers, the same rig dead-drifted along the undercut grass banks, or small gold spinners under the banks between rises.

The event happens over grassy banks, undercut edges and windward shorelines

Spruce MothActive window

Typical here: Jul 20 – Aug 31 · a conifer-forest event — it needs fir and lodgepole on the banks, so it's a Rock Creek / Blackfoot / upper Bitterroot specialty

adultmorning through midday — moths don't enter the water willingly — landings are sporadic and near the conifer banks; fish the imitation LOW in the film with minimal floatant, even fully drowned, with a little movement

When the moths show, just about every run produces — large trout key on them so hard that one pattern carries the whole box for two weeks.

Honest limit: a small drowned-surface moth has no lure analog. The workable rig is a casting bubble with a drowned moth pattern along the timbered banks in the morning; otherwise fish spinners early and late and leave the moth window to the film.

2–3 weeks at best, and day-to-day — fish key on the moths when they show and vanish with them

The event happens over banks under conifers — the moths rarely reach mid-river

Recommendations come from depth structure and seasonal species behavior. Treat them as a starting point, not a guarantee. Contours here are interpolated from real agency depth surveys (state DNR / USACE). Never use for navigation. Always check local regulations.

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Recent catches at Coopers Lake

Shared by DepthScout anglers. Exact spots stay private, always.

No shared catches here yet — be the first.Log a catch from the map above and share it to put Coopers Lake on the board.

Fishing Coopers Lake: what the data says

280-acre lake in Powell County, Montana. The lake tops out around 70 ft. The depth chart is built from real state fisheries GPS surveys, so the humps, channels and drop-offs you see are measured, not guessed. What the data behind the map says about each species, season by season:

Drawn out, this is 280 acres of water rimmed by 3 miles of bank. A shoreline index of 1.3 says round and simple: fish relate to depth changes here, not shoreline features. 10% of the surface is littoral (under ~15 ft) — cover, weeds and forage water. End to end it runs roughly 1.3 mi, about 0.5 mi across. You'll find it in Powell County. Closest neighbour on DepthScout: Lake Otatsy, 8 mi northwest of here.

Brook Trout fishing at Coopers Lake

Spring puts brook trout in skinny water — 2 to 15 ft is the zone. As the season builds they drop to 10 to 30 ft, wintering in 3 to 20 ft. Spring brook trout concentrate at Main-lake point, a prime-rated point around 14 ft. Warm-month bites cluster around early morning and the evening. A small spoon fished deep or a trolled lake-clear wobbler + worm covers the summer program.

Season	Depth	Best window	Start at	Go-to baits
Spring	2 to 15 ft	dawn & dusk	Main-lake point (14 ft)	Small inline spinner (gold), Tiny spoon
Summer	10 to 30 ft	dawn & dusk	open water	Small spoon fished deep, Trolled lake-clear wobbler + worm
Fall	2 to 15 ft	midday & dawn	Main-lake point (14 ft)	Small spoon (orange), Spinner
Winter	3 to 20 ft	dawn	Shallow bay flat (15 ft)	Small jigging spoon, Tungsten jig + plastic

Cutthroat Trout fishing at Coopers Lake

When the water first warms, cutthroat trout slide up into 3 to 15 ft. By summer they slide out to 10 to 35 ft, and by winter most fish are in 10 to 40 ft. If you only fish one area, make it Main-lake point: a point around 14 ft that scores prime in fall. In summer the feeding windows fall in early morning and the evening. Keep a trolled spoon (small) or an inline spinner rigged through the warm months.

Season	Depth	Best window	Start at	Go-to baits
Spring	3 to 15 ft	dawn & dusk	Main-lake point (14 ft)	Inline spinner (silver/gold), Small spoon
Summer	10 to 35 ft	dawn & dusk	Main-lake point (14 ft)	Trolled spoon (small), Inline spinner
Fall	5 to 25 ft	dawn & dusk	Main-lake point (14 ft)	Casting spoon, Inline spinner
Winter	10 to 40 ft	dawn	Main-lake point (14 ft)	Small jigging spoon, Marabou jig

Notable structure

Structure-wise the chart holds 6 features, led in depth by Deep basin at roughly 68 ft.

Deep basin: deep basin, around 68 ft
Break off the point: drop-off, around 60 ft
Shallow bay flat: feeding flat, around 15 ft
Main-lake point: point, around 14 ft
Secondary point: point, around 13 ft
Back-bay flat: feeding flat, around 8 ft

Coopers Lake fishing regulations

Season dates, license requirements, and size and bag limits for Montana waters are set by the Montana Fish, Wildlife & Parks — and special regulations can apply to Coopers Lake specifically, so confirm the current rules before you fish.

Check the official Montana fishing regulations →

Common questions

How deep is Coopers Lake?

Coopers Lake is about 70 ft (21 m) deep at its deepest point. The depth chart here comes from real state fisheries GPS surveys, so the contours reflect measured depths.

What fish are in Coopers Lake?

Anglers target brook trout, cutthroat trout on Coopers Lake.

Where is the best fishing spot on Coopers Lake?

Main-lake point is the top-rated area: a point in about 14 ft of water that rates prime for cutthroat trout in fall. Open the map above to see every rated spot for each species and season.

When is the best time to fish Coopers Lake?

For brook trout, the summer bite is best in early morning and the evening. Each species page section below lists the seasonal windows, and the map shows a live NOW badge when you're inside one.

What are the fishing regulations for Coopers Lake?

Fishing on Coopers Lake is regulated by the Montana Fish, Wildlife & Parks. Check the official Montana regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.

Nearby waters

Lake Otatsy 8 mi · Canyon Lake (Lewis and Clark) 9 mi · Camp Lake (Lewis and Clark) 9 mi · Browns Lake 10 mi · Parker Lake 10 mi · Blackfoot River 13 mi · Heart Lake (Lewis and Clark) 13 mi · Upsata Lake 14 mi · Nevada Reservoir 21 mi · Cottonwood Lake, Middle 21 mi · Harpers Lake 22 mi · Salmon Lake 23 mi

See how Coopers Lake stacks up: best brook trout lakes in Montana · best cutthroat trout lakes in Montana

More water nearby: Powell County fishing maps (8 charts). Browse all Montana fishing maps or see every water on DepthScout. Bathymetry credit: state fisheries survey programs. 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.