Grass Lake Depth Map & Fishing Spots (Rock County, WI)

Lake depth chart

Grass Lake, WI

Max 6 ft

Today's read

Where to start

Fall shiner run window is on — see the hatch outlook

Target species

Species from state lake data, resolved by location. These species come from the Wisconsin DNR's own per-lake fish listing. Where the DNR reports a group rather than a species — “panfish”, “catfish”, “trout” — the specific species are resolved from Wisconsin's fish distribution by this lake's location, depth and habitat, so those are an informed estimate, not a per-species survey. The named gamefish (walleye, musky, bass, pike, sturgeon…) are the DNR's own listing. (The depth chart is a computer-generated estimate from the lake's real shoreline and the DNR's maximum depth — not measured contours.) How we estimate species →

Hatch outlook

Fall shiner runActive window

Typical here: Sep 1 – Oct 31 · colder nights and shortening days start the push in early September — shiners slide out of open water toward warmer shallows and run up the rivers; the Rainy River run off Lake of the Woods is the marquee version

adultdaylight for the jig bite; after dark the shiners stack under dock lights with walleyes and pike mixed right in — follow the bait, not the spot — millions of shiners move together and the predators ride with them; silver profile and flash matter

Concentrates hard but travels — the school (and the walleyes under it) can be off a river mouth one week and miles upriver the next.

Jig-and-minnow is the event's signature — a frozen emerald shiner on a 1/4 oz jig drifted along the run; silver jerkbaits and trolled crankbaits take the roaming fish; blade baits under the schools.

The event happens over river mouths and the first miles upriver, warming shallow shorelines, and rocky points where the displaced bait stacks

Next on this water

Hex (giant mayfly) · mayflyJun 15 – Aug 15 · in ~10 months

Recommendations come from depth structure and seasonal species behavior. Treat them as a starting point, not a guarantee. Contours on this water are approximations. Never use for navigation. Always check local regulations.

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Recent catches at Grass 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 Grass Lake on the board.

Fishing Grass Lake: what the data says

16-acre lake in Rock County, Wisconsin. The lake tops out around 6 ft. The depth picture is modeled, anchored to the true shoreline and the water's published max depth — a scouting aid, never a chart to run a boat by. The rest of this page walks each species through its year, using the map's own scoring.

Drawn out, this is 16 acres of water rimmed by 0.7 miles of bank. At index 1.3 the outline is almost a bowl — read the depth changes, not the shoreline. Nothing on this chart breaks 15 ft, which makes the whole surface littoral: weeds, bait and ambush cover everywhere. End to end it runs roughly 0.3 mi. You'll find it in Rock County. For a second option, Leota Lake lies 3 mi west.

Yellow Perch fishing at Grass Lake

Early season yellow perch use the shallows, holding in 2 to 6 ft. Even in summer they hold at 2 to 6 ft; winter keeps them in 2 to 6 ft. The chart's best answer is Shallow bay flat — weed flat, 3 ft, prime for spring. Best bite is early morning. Tie on a drop-shot micro plastics or a small spoon tipped with worm and you're in the game.

Season	Depth	Best window	Start at	Go-to baits
Spring	2 to 6 ft	midday & dawn	Shallow bay flat (3 ft)	Small jig + curly tail, Perch-pattern micro crank
Summer	2 to 6 ft	dawn	Deep basin (5 ft)	Drop-shot micro plastics, Small spoon tipped with worm
Fall	2 to 6 ft	midday	Deep basin (5 ft)	Jigging spoon (small), Perch rig / spreader
Winter	2 to 6 ft	midday & dawn	Deep basin (5 ft)	Tungsten jig + spikes, Rattle spoon (small)

Crappie fishing at Grass Lake

In spring, crappie run shallow here, mostly 2 to 6 ft. Summer keeps them at 2 to 6 ft, and they winter in 2 to 6 ft. Winter crappie concentrate at Deep basin, a prime-rated deep basin around 5 ft. Fish it in early morning and the evening and you'll meet the bite. You won't need more than a jig trolled/spider-rigged or a small crankbait (trolled) most summer days.

Season	Depth	Best window	Start at	Go-to baits
Spring	2 to 6 ft	midday & dawn	Shallow bay flat (3 ft)	1/16 oz jig + tube, Curly-tail grub
Summer	2 to 6 ft	dawn & dusk	Shallow bay flat (3 ft)	Jig trolled/spider-rigged, Small crankbait (trolled)
Fall	2 to 6 ft	dawn	Shallow bay flat (3 ft)	Jig + minnow combo, Small swimbait (1.5-2")
Winter	2 to 6 ft	midday	Deep basin (5 ft)	Tungsten jig + soft plastic, Tiny jigging spoon

Bluegill fishing at Grass Lake

Start shallow in spring: bluegill sit in 1 to 6 ft that time of year. They don't go far with the seasons — 2 to 6 ft covers summer, 2 to 6 ft covers winter. Top water on the chart: Shallow bay flat, a weed flat in the 3 ft range, prime in spring. Fish it in early morning and the evening and you'll meet the bite. Throw a small sponge spider (fly) or a micro tube jig until the fish tell you otherwise.

Season	Depth	Best window	Start at	Go-to baits
Spring	1 to 6 ft	midday & dusk	Shallow bay flat (3 ft)	1/32 oz jig + micro plastic, Tiny popper (evenings)
Summer	2 to 6 ft	dawn & dusk	Shallow bay flat (3 ft)	Small sponge spider (fly), Micro tube jig
Fall	2 to 6 ft	midday	Shallow bay flat (3 ft)	Micro jig + waxworm, Small spoon tipped
Winter	2 to 6 ft	midday	Deep basin (5 ft)	Tungsten ice jig + plastic, Tiny spoon

Notable structure

Count 4 structure marks on this chart. The deepest, Deep basin, sits near 5 ft.

Deep basin: deep basin, around 5 ft
Shallow bay flat: weed flat, around 3 ft
Back-bay flat: weed flat, around 3 ft
Shoreline break: drop-off, around 3 ft

Grass Lake fishing regulations

Season dates, license requirements, and size and bag limits for Wisconsin waters are set by the Wisconsin DNR — and special regulations can apply to Grass Lake specifically, so confirm the current rules before you fish.

Check the official Wisconsin fishing regulations →

Common questions

How deep is Grass Lake?

Grass Lake is about 6 ft (2 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.

What fish are in Grass Lake?

Anglers target yellow perch, crappie, bluegill on Grass Lake. These come from the Wisconsin DNR's per-lake fish listing; where the DNR lists a group (panfish, catfish, trout) the specific species are resolved from Wisconsin's fish distribution by the lake's location, depth and habitat.

Where is the best fishing spot on Grass Lake?

Shallow bay flat is the top-rated area: a weed flat in about 3 ft of water that rates prime for yellow perch in spring. The map above holds the full rated-spot list for every species and season.

When is the best time to fish Grass Lake?

For yellow perch, 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.

What are the fishing regulations for Grass Lake?

Fishing on Grass Lake is regulated by the Wisconsin DNR. Check the official Wisconsin regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.

Nearby waters

Leota Lake 3 mi · Gibbs Lake 3 mi · Little Gibbs Lake 3 mi · Stoughton Millpond 429 8 mi · Willies Pond 9 mi · Lake Kegonsa 12 mi · Rock River (WI) 13 mi · Rice Lake 13 mi · Decatur Lake 13 mi · Clear Lake 13 mi · Mud Lake 14 mi · Lions Park Pond 15 mi

See how Grass Lake stacks up: best crappie lakes in Wisconsin · best bluegill lakes in Wisconsin · best yellow perch lakes in Wisconsin

More water nearby: Rock County fishing maps (12 charts). Browse all Wisconsin 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.

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