Lake depth chart
Today's read
Rating depth structure for largemouth bass.
Shared by DepthScout anglers. Exact spots stay private, always.
145-acre lake in Iron County, Wisconsin. The lake tops out around 55 ft. The contours are modeled from the water's real shoreline and maximum depth. Treat them as a rough guide, and never use them for navigation. Every species below gets its seasonal read from the same numbers driving the chart.
Martha Lake maps at 146 acres behind 3.1 miles of shoreline. With a 1.8 development index there's bank structure worth casting at, in moderation. Roughly 54% of the water is 15 ft or less as modeled, the band where the food chain lives. Tip to tip the water measures near 1 mi with a 0.5-mi widest point. It sits in Iron County. Grand Portage Lake sits 1 mi west — the closest neighbouring chart.
Spring puts walleye in skinny water — 4 to 15 ft is the zone. Warm water sends them out to 15 to 35 ft; cold water stacks them in 20 to 40 ft. Break off the point is the standout, a drop-off at roughly 25 ft, rated prime for fall walleye. Plan around the evening and early morning in the warm months. A crawler harness on bottom bouncer or a deep crankbait (trolled) covers the summer program.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 4 to 15 ft | dusk & dawn | Main-lake point (14 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 15 to 35 ft | dusk & dawn | Break off the point (25 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 12 to 40 ft | dusk & night | Break off the point (25 ft) | Jigging rap, Jig + big minnow |
| Winter | 20 to 40 ft | dusk & dawn | Break off the point (25 ft) | Jigging spoon + minnow head, Rattle bait |
Start shallow in spring: yellow perch sit in 3 to 12 ft that time of year. Warm water sends them out to 10 to 30 ft; cold water stacks them in 15 to 35 ft. Top water on the chart: Shallow bay flat, a weed flat in the 6 ft range, prime in spring. Fish it in early morning and you'll meet the bite. Throw a drop-shot micro plastics or a small spoon tipped with worm until the fish tell you otherwise.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | midday & dawn | Shallow bay flat (6 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 10 to 30 ft | dawn | Break off the point (25 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 12 to 35 ft | midday | Break off the point (25 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 15 to 35 ft | midday & dawn | Break off the point (25 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Come spring, look for northern pike tight to the bank in 2 to 8 ft. They move out to 8 to 20 ft in summer and finish the year down in 5 to 15 ft. If you only fish one area, make it Shallow bay flat: a weed flat around 6 ft that scores prime in spring. Best bite is early morning and the evening. A bucktail or a weedless spoon over cabbage is the honest summer answer here.
| 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 bay flat (6 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 |
When the water first warms, muskellunge slide up into 3 to 12 ft. By summer they slide out to 8 to 25 ft, and by winter most fish are in 15 to 35 ft. If you only fish one area, make it Break off the point: a drop-off around 25 ft that scores prime in fall. In summer the feeding windows fall in the evening and early morning. Keep a double-10 bucktail or a topwater (walk-the-dog / creeper) rigged through the warm months.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dusk | Shallow bay flat (6 ft) | Smaller bucktail (#8 blades), 6" glide bait |
| Summer | 8 to 25 ft | dusk & dawn | Main-lake point (14 ft) | Double-10 bucktail, Topwater (walk-the-dog / creeper) |
| Fall | 8 to 30 ft | midday & dusk | Break off the point (25 ft) | Big rubber (Bull Dawg style), 10"+ glide bait |
| Winter | 15 to 35 ft | midday | Break off the point (25 ft) | Large rubber, crawled slow |
Come spring, look for smallmouth bass tight to the bank in 3 to 12 ft. They move out to 10 to 30 ft in summer and finish the year down in 20 to 45 ft. If you only fish one area, make it Main-lake point: a point around 14 ft that scores prime in fall. Best bite is early morning and the evening. A drop shot (goby/minnow) or a ned rig is the honest summer answer here.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dawn & dusk | Main-lake point (14 ft) | Ned rig, Tube jig |
| Summer | 10 to 30 ft | dawn & dusk | Break off the point (25 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 8 to 25 ft | midday & dawn | Main-lake point (14 ft) | Jerkbait, Blade bait |
| Winter | 20 to 45 ft | midday | Break off the point (25 ft) | Blade bait, Hair jig |
When the water first warms, largemouth bass slide up into 2 to 10 ft. Summer is an 8 to 20 ft game here, winter a 15 to 35 ft one. Start at Shallow bay flat. It's a weed flat holding about 6 ft of water and rates prime come spring. The feeding windows run early morning and the evening. Keep a texas-rigged 10" worm or a deep-diving crankbait rigged through the warm months.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 10 ft | dawn & dusk | Shallow bay flat (6 ft) | Spinnerbait, Chatterbait |
| Summer | 8 to 20 ft | dawn & dusk | Main-lake point (14 ft) | Texas-rigged 10" worm, Deep-diving crankbait |
| Fall | 4 to 15 ft | midday & dawn | Main-lake point (14 ft) | Squarebill crankbait (shad), Spinnerbait |
| Winter | 15 to 35 ft | midday | Break off the point (25 ft) | Blade bait, Jigging spoon |
Martha Lake also holds crappie (10 to 25 ft in summer), bluegill (4 to 15 ft in summer), pumpkinseed (2 to 10 ft in summer). Pick any of them on the map above for rated spots and bait picks.
Martha Lake carries 6 mapped structure features, topping out (or rather bottoming out) at Deep basin, about 47 ft down.
Season dates, license requirements, and size and bag limits for Wisconsin waters are set by the Wisconsin DNR — and special regulations can apply to Martha Lake specifically, so confirm the current rules before you fish.
Check the official Wisconsin fishing regulations →
Martha Lake is about 55 ft (17 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, muskellunge, smallmouth bass, largemouth bass, crappie, bluegill, pumpkinseed on Martha 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.
Break off the point is the top-rated area: a drop-off in about 25 ft of water that rates prime for walleye in fall. Every other rated spot, per species and season, is on the map above.
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 Martha 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.
Grand Portage Lake 1 mi · Little Martha Lake 1 mi · San Domingo Lake 1 mi · Brush Lake 1 mi · Echo Lake 1 mi · Payment Lake 2 mi · Tamarack Lake 2 mi · Net Lake 2 mi · Wallace Lake 2 mi · Margaret Lake 2 mi · Mercer Lake 2 mi · Allen Lake 2 mi
See how Martha Lake stacks up: best largemouth bass lakes in Wisconsin · best smallmouth bass lakes in Wisconsin · best walleye lakes in Wisconsin · best northern pike lakes in Wisconsin
More water nearby: Iron County fishing maps (158 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.