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Rating depth structure for walleye.
Recent public catches load as you reach this section.
Marshalltown to Iowa City (Coralville tailwater) The river tops out around 8 ft. This chart interpolates between a real shoreline and a known maximum depth. It will point you at likely water, but it is not a navigation product. Species by species, here's what the data says the year looks like.
The drawn water covers 12,253 acres wrapped in 215.6 miles of bank. With a shoreline index of 13.9, this water is all arms and coves — edge habitat well beyond its acreage. There is no deep basin to speak of — the entire surface is under ~15 ft, prime weed water end to end. Tip to tip the water measures near 76.4 mi with a 9.2-mi widest point. It sits in Benton County. If the bite dies, Hannen Lake is 6 mi to the east.
Early season channel catfish use the shallows, holding in 2 to 8 ft. Even in summer they hold at 2 to 8 ft; winter keeps them in 2 to 8 ft. The chart's best answer is Outside-bend hole (mile 6.2) — creek channel, 6 ft, prime for summer. 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 | 2 to 8 ft chart-limited; documented 3 to 12 ft | dusk | Outside-bend hole (mile 6.2) (6 ft) | |
| Summer | 2 to 8 ft chart-limited; documented 8 to 25 ft | night & dusk | Outside-bend hole (mile 6.2) (6 ft) | |
| Fall | 2 to 8 ft chart-limited; documented 10 to 30 ft | dusk | Outside-bend hole (mile 6.2) (6 ft) | |
| Winter | 2 to 8 ft chart-limited; documented 20 to 40 ft | midday | Outside-bend hole (mile 6.2) (6 ft) |
Start shallow in spring: walleye sit in 2 to 8 ft that time of year. They don't go far with the seasons — 2 to 8 ft covers summer, 2 to 8 ft covers winter. Top water on the chart: Riffle & run (mile 2.5), a rock pile in the 3 ft range, prime in spring. Fish it in the evening and early morning and you'll meet the bite. Throw a crawler harness on bottom bouncer or a deep crankbait (trolled) until the fish tell you otherwise.
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 chart-limited; documented 4 to 15 ft | dusk & dawn | Riffle & run (mile 2.5) (3 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 2 to 8 ft chart-limited; documented 15 to 35 ft | dusk & dawn | Current seam (mile 0.6) (4 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 2 to 8 ft chart-limited; documented 12 to 40 ft | dusk & night | Outside-bend hole (mile 6.2) (6 ft) | Jigging rap, Jig + big minnow |
| Winter | 2 to 8 ft chart-limited; documented 20 to 40 ft | dusk & dawn | Outside-bend hole (mile 6.2) (6 ft) | Jigging spoon + minnow head, Rattle bait |
Early season flathead catfish use the shallows, holding in 2 to 8 ft. Even in summer they hold at 2 to 8 ft; winter keeps them in 2 to 8 ft. Put Outside-bend hole (mile 6.2) first on the milk run — a creek channel near 6 ft that grades prime for summer. In summer the feeding windows fall in 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 | 2 to 8 ft chart-limited; documented 5 to 20 ft | night & dusk | Outside-bend hole (mile 6.2) (6 ft) | |
| Summer | 2 to 8 ft chart-limited; documented 8 to 30 ft | night & dusk | Outside-bend hole (mile 6.2) (6 ft) | |
| Fall | 2 to 8 ft chart-limited; documented 10 to 35 ft | night & dusk | Outside-bend hole (mile 6.2) (6 ft) | |
| Winter | 2 to 8 ft chart-limited; documented 20 to 45 ft | midday | Outside-bend hole (mile 6.2) (6 ft) |
Come spring, look for common carp tight to the bank in 2 to 8 ft. Through summer count on 2 to 8 ft; the winter hold is 2 to 8 ft. Start at Outside-bend hole (mile 6.2). It's a creek channel holding about 6 ft of water and rates prime come fall. Prime time lands in early morning 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 | 2 to 8 ft chart-limited; documented 2 to 10 ft | midday & dawn | open water | |
| Summer | 2 to 8 ft chart-limited; documented 3 to 15 ft | dawn & dusk | open water | |
| Fall | 2 to 8 ft chart-limited; documented 5 to 18 ft | midday | Outside-bend hole (mile 6.2) (6 ft) | |
| Winter | 2 to 8 ft chart-limited; documented 10 to 30 ft | midday | Outside-bend hole (mile 6.2) (6 ft) |
When the water first warms, freshwater drum slide up into 2 to 8 ft. There's no big seasonal slide here — summer means 2 to 8 ft, winter 2 to 8 ft. If you only fish one area, make it Outside-bend hole (mile 6.2): a creek channel around 6 ft that scores prime in summer. In summer the feeding windows fall in the evening. Keep a jig + crawler combo or a small crankbait (slow) 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 chart-limited; documented 5 to 20 ft | midday & dawn | Outside-bend hole (mile 6.2) (6 ft) | Jig + curly tail (bounced), Small blade bait |
| Summer | 2 to 8 ft chart-limited; documented 8 to 30 ft | dusk | Outside-bend hole (mile 6.2) (6 ft) | Jig + crawler combo, Small crankbait (slow) |
| Fall | 2 to 8 ft chart-limited; documented 10 to 35 ft | midday | Outside-bend hole (mile 6.2) (6 ft) | Blade bait (vertical), Jigging spoon |
| Winter | 2 to 8 ft chart-limited; documented 15 to 45 ft | midday | Outside-bend hole (mile 6.2) (6 ft) | Jigging spoon (slow) |
Count 49 structure marks on this chart. The deepest, Outside-bend hole (mile 6.2), sits near 6 ft.
Access data: Iowa DNR — Boat Ramps. Confirm conditions and fees locally before you launch.
Season dates, license requirements, and size and bag limits for Iowa waters are set by the Iowa DNR — and special regulations can apply to Iowa River specifically, so confirm the current rules before you fish.
Check the official Iowa fishing regulations →
Iowa River is about 8 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.
Anglers target channel catfish, walleye, flathead catfish, common carp, freshwater drum on Iowa River.
Outside-bend hole (mile 6.2) is the top-rated area: a creek channel in about 6 ft of water that rates prime for channel catfish in summer. Open the map above to see every rated spot for each species and season.
For channel catfish, the summer bite is best in after dark 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 Iowa River 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.
Hannen Lake 6 mi · Iowa Lake (Iowa Co.) 16 mi · Otter Creek Lake 20 mi · Rodgers Park Lake 24 mi · Diamond Lake 26 mi · Kent Park Lake 27 mi · Pleasant Creek Lake 27 mi · Arbor Lake 28 mi · Casey Lake (aka Hickory Hills Lake) 28 mi · Cedar River 28 mi · Hawthorn Lake 29 mi · Prairie Park Fishery 31 mi
See how Iowa River stacks up: best walleye lakes in Iowa · best channel catfish lakes in Iowa · best flathead catfish lakes in Iowa · best freshwater drum lakes in Iowa
Browse all Iowa fishing maps. 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.