Pool 4, and what a gauge at Red Wing counts
Pool 4 is the water between Lock and Dam 3 above Red Wing and Lock and Dam 4 at Alma, Wisconsin. Muddy Waters River Guiding, based at Red Wing, describes it as Lake Pepin, roughly 23 miles long, with about 12 miles of river above it and 12 below, 47 miles in all; Coulee Land Company's guide calls the same stretch 44 miles. Everything on this page is about that pool, not the Twin Cities pools or the river at Winona, which the hub's other Mississippi gauges cover. The page's gauge, USGS 05355250 at Red Wing, reads discharge below the dam with 46,900 square miles above it, which means it is counting the whole upper Mississippi plus the Minnesota and St. Croix rivers. It is a measure of how hard the current is running through the tailwater and over the wing dams, not of anything local.
The record at Red Wing since 1995 gives the shape of the year: monthly means of about 16,100 cfs in January, 16,600 in February, 29,100 in March, 62,900 in April, 52,300 in May, 39,100 in June, 35,500 in July, 20,600 in August, 18,900 in September, 29,500 in October, 26,800 in November and 22,300 in December. Coulee Land Company's fishing guide draws the line that matters: when flow tops 25,000 cfs the main channel becomes a treadmill and the fish and the boats move to the edges. That line and the late-summer and winter means set the 10,000 to 25,000 cfs band on this page. The April and May numbers show why the tailwater run is fished in March, before the snowmelt arrives.
The five miles below Lock and Dam 3, and the 300 feet you cannot fish
Coulee's guide puts the March and April fishing in the five-mile stretch below Lock and Dam 3, where walleye stack as water temperatures climb from 34 to 42 degrees, and describes the technique as vertical jigging 1/4 to 3/8 ounce hair jigs in current the guide calls 3 mph, with riprap shorelines that warm the adjacent water a couple of degrees drawing bait and walleye in the afternoon. Muddy Waters adds why this water is open at all in February: a power plant above the dam discharges warm water into the bottom of Pool 3 that keeps the top of Pool 4 open through winter, and Everts Resort at Hager City, on the Wisconsin side below the dam, keeps its ramps plowed and open all winter, along with a year-round ramp on the Wisconsin back channel.
The closure is the rule to know. Minnesota's 2026 border-water pages make it a fish sanctuary: no fishing within 300 feet below Lock and Dam 3 near Red Wing, or below Lock and Dam 4 at Alma, from March 1 through April 30. Wisconsin's guide prints the same closure through April 29. Both states also prohibit any method but hook and line within 200 feet of any lock or dam on the Mississippi. Coulee's practical note is that the Red Wing public ramp can run three-hour waits at the peak of the run and that the Bay City ramp is the way around it.
June to October: wing dams, Lake Pepin and the mud line
When the water crosses 70 degrees in June, Coulee says the fish leave the deep dam water for the forty-plus wing dams between Red Wing and Lake City, holding on the tip where the current breaks in 12 to 18 feet, and the presentation becomes a three-way rig with a blade or a crawler harness. Each wing dam has a face, a tip and a scour hole off the tip, and the guide's boat control advice is to hold 30 feet above the dam and cast onto the rocks. Muddy Waters lists the rest of the structure: closing dams, miles of riprap, the Wisconsin back channel, sloughs and cuts, more wing dams down by Wabasha, and the mouths of Hay Creek, the Cannon, the Vermillion and the Rush.
Lake Pepin changes the game to volume. Coulee describes trolling the flats with lead core and looking for the mud line where the Chippewa River pushes silt into the pool, and in October a numbers game trolling crankbaits through the deep main-channel transitions as shad move into backwaters and side channels. The tailrace rarely freezes, so December and January are jigging blade baits and jigging Raps in the slack eddies below the dam. Smallmouth are the summer bonus on the same wing dams and riprap, and the border rule keeps them open all year.
The border table: four walleye, one over 20, all year
Because Pool 4 is Wisconsin-Minnesota border water, either state's license is good from shore to shore, though residents of each state must carry their own state's license and everyone must carry a paper copy. New in Minnesota's 2026 regulations, and matched in Wisconsin's 2026-2027 guide: on Mississippi River Pools 3 through 8 including Lake Pepin, walleye and sauger are open continuously with four combined, a 15-inch minimum for walleye and only one walleye or sauger over 20 inches. Minnesota's inland portions of Pool 3 now follow the same rule. Largemouth and smallmouth bass are open all year, five at 14 inches. Northern pike are three with only one over 30 inches. Muskellunge run May 23 through November 30 with one fish at 50 inches.
Catfish are ten combined with only one over 30 inches, flatheads from April 1 through November 30. Lake sturgeon below the Red Wing dam and in Lake Pepin are catch and release from June 16 through April 14 with no tag needed; above the dam to the St. Croix mouth the window is June 16 through March 1. Shovelnose sturgeon below the Red Wing dam are open continuously with three fish. Two lines are allowed with a single bait on each, motor trolling is permitted, live rusty and native crayfish may be used for bait on the Mississippi but nowhere else on the border waters, and any fish hooked outside the mouth goes back immediately.
The season in bait, from hair jigs to lead core
No hatch chart exists for a pool this size, so the table on this page is the forage calendar the two guide services describe. Late winter and early spring are hair jigs and minnows in the tailwater; late spring and summer move to crawler harnesses, three-way rigs and crayfish and minnow imitations on the wing dams; fall is crankbaits pulled on lead core through Lake Pepin and the channel edges as shad school up; winter is blade baits in the open tailrace. Emerald shiners and gizzard shad are the bait Coulee names at the dams, which is what the minnow and shad rows stand for.