Pool 9 fishing, from Genoa down to Lynxville

What is Pool 9, exactly?

The water held back by Lock and Dam 9, which sits at river mile 647.9, about three river miles below Lynxville and thirteen above Prairie du Chien. It runs upstream 31.3 miles to Lock and Dam 8 at Genoa. The dam opened in 1937 and was rehabilitated between 1989 and 2006. The Corps operates the pool against a primary control point at Lansing, Iowa rather than at the dam itself, which is why the Lansing stage is the number local anglers quote.

One major tributary feeds it: the Upper Iowa River, draining 1,060 square miles, entering at river mile 671. Everything else is small creeks. Compared with Pool 8 upstream, which takes both the Root and the La Crosse, that makes Pool 9 slower to muddy after a regional rain — the water you find on a Saturday is more likely to resemble what you found on the Thursday.

The pool is bordered by Crawford County, Wisconsin and Allamakee County, Iowa, and like Pool 8 it lies inside the Upper Mississippi River National Wildlife and Fish Refuge, which publishes maps marking sanctuaries and closed areas pool by pool.

Why do the limits change in the middle of the pool?

Because Wisconsin regulates boundary water by which state is on the other bank, and on Pool 9 that answer changes partway down. Above roughly river mile 673.8 the far bank is Minnesota, so chapter NR 21 applies. Below it the far bank is Iowa, so chapter NR 22 applies. Both chapters list Pool 9 in their tables, which is the tell — the pool genuinely sits under both.

Walleye, sauger and bass are the same throughout: six walleye and sauger in aggregate, fifteen-inch minimum on walleye, nothing from twenty to twenty-seven inches kept and only one fish over twenty-seven; five bass in aggregate at fourteen inches. Lake sturgeon and paddlefish have no open season under either chapter. It is catfish, pike and panfish that shift, and they shift by a lot.

Which license covers you on Pool 9?

Three states touch this pool, which sounds worse than it is. Reciprocity means a valid license from an adjoining state covers the boundary waters, defined by the railroad tracks that parallel both banks. The exception that trips people is the resident rule: residents must hold their own state's resident license when fishing their own state's boundary water.

Because Pool 9 borders Minnesota at the top and Iowa at the bottom, an Iowa resident fishing the upper pool and a Minnesota resident fishing the lower pool are in genuinely different positions. OurMississippi River license findertakes residency, where you are fishing, your age and the trip length and returns the license to buy with the current price. The same two free weekends apply here as elsewhere on the boundary waters: the first in June and the third in January.

Where can you get a boat in the water?

Blackhawk Park is the main one — Three miles north of De Soto off Wisconsin State Highway 35, on the main channel, at E590 County Road BI, De Soto, Wisconsin 54624. The Corps of Engineers runs it and calls it the largest recreation area in Pool 9 and the only Corps-staffed campground on the Upper Mississippi in the St. Paul District. Two ramps: one on the main channel, one on Green Lake for the backwaters. There is an accessible fishing dock and fish cleaning stations on site.

Ferryville, Lynxville and the Iowa towns down the west bank all have landings as well. For anything beyond Blackhawk, theWisconsin boat access inventory is the maintained list, and therefuge pool maps show which backwaters are closed before you commit to a run.

What should you target on Pool 9?

The walleye structure here rewards a different plan than Pool 8. Six fish instead of four, but a protected slot from twenty to twenty-seven inches, which means the pool is managed to grow big fish and you cannot keep the mid-size ones. Fill the bag with fish under twenty and put the rest back. For a length-to-weight check on a legal fish, use thewalleye weight calculator.

Channel catfish are the other headline, and in the lower half there is no bag limit on them at all. Whether that is a reason to keep a boatful is a separate question from whether it is legal. Ourchannel catfish weight calculator will give you a weight from a length measurement, which is the more useful thing to do with most of them.

Largemouth bass hold in the backwaters off Green Lake and the sloughs behind the islands; thelargemouth bass calculator answers the five-pound question as a length window rather than a single number. Panfish limits are the generous ones below the Iowa line and the tight ones above it, so check which half you are in before you start counting.

When is Pool 9 worth the drive?

Every headline species on this pool has a continuous season, so the calendar rarely locks you out — the drive and the water do. From La Crosse or Prairie du Chien you are committing an hour-plus for a pool that rewards low light on the dam face and patience in the Green Lake backwaters. Midday behind a rising high is when we stay home; a falling barometer into dawn against current is when the protected-slot walleye fishery is worth the fuel.

Blackhawk Park is the default put-in for the lower half: main-channel ramp for the dam and current seams, Green Lake ramp when you are hunting largemouth in the flooded timber. Ferryville and Lynxville landings cover the Wisconsin bank farther south. The gauge panel at the top of this page and thebest fishing time calculator cover the two halves of the decision: what the river is doing, and whether the hour is worth taking.

Questions anglers ask about Pool 9

How big is Pool 9?

Pool 9 covers 29,125 acres at its project pool elevation of 620.0 feet, with 90 miles of shoreline, and runs 31.3 river miles from Lock and Dam 8 at Genoa down to Lock and Dam 9 near Lynxville. That makes it both longer and larger than Pool 8 upstream.

Why do catfish limits change partway down Pool 9?

Because the Iowa-Minnesota state line crosses the pool at about river mile 673.8, near New Albin, Iowa. Above that point the water is Wisconsin-Minnesota boundary water under chapter NR 21, which caps catfish at ten in aggregate. Below it the water is Wisconsin-Iowa boundary water under chapter NR 22, which sets no catfish bag limit at all.

How many walleye can you keep on Pool 9?

Six walleye and sauger in aggregate under Wisconsin rules, with a 15-inch minimum on walleye. Walleye between 20 and 27 inches must be released and only one fish longer than 27 inches may be kept. Both boundary-water chapters agree on this one, so it holds for the whole pool.

Is there a live gauge inside Pool 9?

No working one. The United States Geological Survey site at Lock and Dam 9 near Lynxville is registered but publishes no real-time data, so this page uses site 05389500 at McGregor, Iowa, which sits below Lock and Dam 9 in Pool 10. It tracks the river rising and falling but it is not Pool 9 pool stage, and we would rather say so than present it as something it is not.

Which tributary feeds Pool 9?

The Upper Iowa River, draining 1,060 square miles, entering at river mile 671. Apart from several small creeks it is the only major tributary in the pool, which makes Pool 9 less prone to sudden tributary-driven colour changes than Pool 8 with its two.

Fishing upstream of the dam at Genoa instead? The bag limits tighten. OurPool 8 fishing guide covers the 23.3 miles up to La Crosse, where walleye drop to four fish and only one may be longer than twenty inches.