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.
17-acre lake near Monona County. The lake tops out around 18 ft. The depth chart comes from published agency bathymetric survey data, so the contours are survey-derived rather than computer-modeled. The rest of this page walks each species through its year, using the map's own scoring.
The outline encloses 17 acres, worked by 0.8 miles of shoreline. Nearly circular (index 1.4), so the story is the bottom, not the bank. Littoral water — the productive band under ~15 ft — makes up 97% of this chart. End to end it runs roughly 0.4 mi. It sits in Monona County. Nelson Park Lake sits 11 mi southeast — the closest neighbouring chart.
When the water first warms, crappie slide up into 2 to 8 ft. Summer is a 5 to 18 ft game here, winter a 5 to 18 ft one. Start at Deep basin. It's a deep basin holding about 17 ft of water and rates prime come winter. The feeding windows run early morning and the evening. Keep a jig trolled/spider-rigged or a small crankbait (trolled) 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 | 2 to 8 ft | midday & dawn | Shallow bay flat (2 ft) | 1/16 oz jig + tube, Curly-tail grub |
| Summer | 5 to 18 ft chart-limited; documented 10 to 25 ft | dawn & dusk | Break off the point (6 ft) | Jig trolled/spider-rigged, Small crankbait (trolled) |
| Fall | 5 to 18 ft chart-limited; documented 8 to 20 ft | dawn | Break off the point (6 ft) | Jig + minnow combo, Small swimbait (1.5-2") |
| Winter | 5 to 18 ft chart-limited; documented 15 to 35 ft | midday | Deep basin (17 ft) | Tungsten jig + soft plastic, Tiny jigging spoon |
Come spring, look for bluegill tight to the bank in 1 to 6 ft. Expect a summer slide to 4 to 15 ft, then a winter hold in 5 to 18 ft. Start at Shallow bay flat. It's a weed flat holding about 2 ft of water and rates prime come spring. Prime time lands in early morning and the evening. A small sponge spider (fly) or a micro tube jig is the honest summer answer here.
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 | 1 to 6 ft | midday & dusk | Shallow bay flat (2 ft) | 1/32 oz jig + micro plastic, Tiny popper (evenings) |
| Summer | 4 to 15 ft | dawn & dusk | Shallow bay flat (2 ft) | Small sponge spider (fly), Micro tube jig |
| Fall | 6 to 18 ft | midday | Break off the point (6 ft) | Micro jig + waxworm, Small spoon tipped |
| Winter | 5 to 18 ft chart-limited; documented 10 to 25 ft | midday | Deep basin (17 ft) | Tungsten ice jig + plastic, Tiny spoon |
Come spring, look for largemouth bass tight to the bank in 2 to 10 ft. They move out to 5 to 18 ft in summer and finish the year down in 5 to 18 ft. If you only fish one area, make it Shallow bay flat: a weed flat around 2 ft that scores prime in spring. Best bite is early morning and the evening. A texas-rigged 10" worm or a deep-diving crankbait is the honest summer answer here.
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 | 2 to 10 ft | dawn & dusk | Shallow bay flat (2 ft) | Spinnerbait, Chatterbait |
| Summer | 5 to 18 ft chart-limited; documented 8 to 20 ft | dawn & dusk | Break off the point (6 ft) | Texas-rigged 10" worm, Deep-diving crankbait |
| Fall | 4 to 15 ft | midday & dawn | Main-lake point (3 ft) | Squarebill crankbait (shad), Spinnerbait |
| Winter | 5 to 18 ft chart-limited; documented 15 to 35 ft | midday | Break off the point (6 ft) | Blade bait, Jigging spoon |
Come spring, look for channel catfish tight to the bank in 3 to 12 ft. They move out to 5 to 18 ft in summer and finish the year down in 5 to 18 ft. If you only fish one area, make it Deep basin: a deep basin around 17 ft that scores prime in winter. Best bite is after dark and the evening.
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 | dusk | Shallow bay flat (2 ft) | |
| Summer | 5 to 18 ft chart-limited; documented 8 to 25 ft | night & dusk | Deep basin (17 ft) | |
| Fall | 5 to 18 ft chart-limited; documented 10 to 30 ft | dusk | Deep basin (17 ft) | |
| Winter | 5 to 18 ft chart-limited; documented 20 to 40 ft | midday | Deep basin (17 ft) |
The spring pattern is a shallow one: yellow perch in 3 to 12 ft. Midsummer fish sit out in 5 to 18 ft before dropping to 5 to 18 ft for winter. The spot to know is Deep basin, a deep basin in about 17 ft of water that rates prime for yellow perch in fall. Plan around early morning in the warm months. Summer baits: a drop-shot micro plastics or a small spoon tipped with worm gets it done.
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 (2 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 5 to 18 ft chart-limited; documented 10 to 30 ft | dawn | Deep basin (17 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 5 to 18 ft chart-limited; documented 12 to 35 ft | midday | Deep basin (17 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 5 to 18 ft chart-limited; documented 15 to 35 ft | midday & dawn | Deep basin (17 ft) | Tungsten jig + spikes, Rattle spoon (small) |
In spring, walleye run shallow here, mostly 4 to 15 ft. Midsummer fish sit out in 5 to 18 ft before dropping to 5 to 18 ft for winter. Fall walleye concentrate at Break off the point, a prime-rated drop-off around 6 ft. Fish it in the evening and early morning and you'll meet the bite. You won't need more than a crawler harness on bottom bouncer or a deep crankbait (trolled) 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 | 4 to 15 ft | dusk & dawn | Main-lake point (3 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 5 to 18 ft chart-limited; documented 15 to 35 ft | dusk & dawn | Break off the point (6 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 5 to 18 ft chart-limited; documented 12 to 40 ft | dusk & night | Break off the point (6 ft) | Jigging rap, Jig + big minnow |
| Winter | 5 to 18 ft chart-limited; documented 20 to 40 ft | dusk & dawn | Deep basin (17 ft) | Jigging spoon + minnow head, Rattle bait |
The chart marks 4 structure features on Oldham Lake; the deepest is Deep basin at about 17 ft.
Season dates, license requirements, and size and bag limits for Iowa waters are set by the Iowa DNR — and special regulations can apply to Oldham Lake specifically, so confirm the current rules before you fish.
Check the official Iowa fishing regulations →
Oldham Lake is about 18 ft (5 m) deep at its deepest point. The depth chart comes from published agency bathymetric survey data, so the contours are survey-derived rather than computer-modeled.
Anglers target crappie, bluegill, largemouth bass, channel catfish, yellow perch, walleye on Oldham Lake. This isn't a survey of the water — none is published for it — but an informed estimate from the species common to the region, narrowed by this water's depth, size and each species' range.
Deep basin is the top-rated area: a deep basin in about 17 ft of water that rates prime for crappie in winter. Open the map above to see every rated spot for each species and season.
For crappie, 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.
Fishing on Oldham Lake is regulated by the Iowa DNR. Check the official Iowa regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.
Nelson Park Lake 11 mi · Loess Hills State Forest - Jones Creek 12 mi · Willow Lake 16 mi · Blue Lake 19 mi · Manteno Park Pond 20 mi · Crawford Creek Impoundment 20 mi · Yellow Smoke Park Lake 24 mi · Moorehead Park Pond 29 mi · Little Sioux Park Lake 30 mi · Summit Lake 31 mi, NE · Snyder Bend Lake 34 mi · Browns Lake 35 mi
See how Oldham Lake stacks up: best largemouth bass lakes in Iowa · best walleye lakes in Iowa · best crappie lakes in Iowa · best bluegill lakes in Iowa
Browse all Iowa fishing maps. See every water on DepthScout. Bathymetry: published agency survey data. 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.