Appleton in figures, and where each one comes from
Census QuickFacts puts the population estimate for Appleton, WI at 75,452 on July 1, 2025 (V2025). The Census of April 1, 2020 counted 75,644. QuickFacts also gives the city a land area of 24.79 square miles in 2020, with a 2020 population per square mile of 3,051.5.
The closest NOAA engineering weather station to Appleton is at Green Bay, about 21 miles northeast of Appleton, at an elevation of 702 feet. For Green Bay, NOAA's engineering weather data lists:
- a 1% summer design temperature of 85°F, with a mean coincident wet-bulb temperature of 72°F;
- a 99% winter design temperature of -7°F;
- a 50-year basic wind speed of 90 mph, as a 3-second gust at 33 feet;
- a 100-year rainfall rate of 2.5 inches per hour;
- about 66 freeze-thaw cycles in an average year.
All five belong to the Green Bay station, about 21 miles from Appleton. They are not measurements taken in Appleton or at your foundation.
Find out what kind of wet you have
A damp basement can be wet for very different reasons, and each one has a different fix. Before you call anyone, spend a few weeks writing down what you see:
- the date, and whether it had rained, snow had been melting, or the air was simply warm and sticky;
- exactly where the water shows: one corner, a line along the floor edge, a single crack, under a window, or spread across a whole wall;
- whether it appears as drips, a trickle, a puddle, or a film of droplets;
- any white, chalky crust on the concrete, which is mineral left behind as water dries on the surface.
A simple test helps separate condensation from water moving through the wall. Tape a square of plastic sheeting, roughly a foot on each side, tight to the bare wall and leave it two days. Droplets on the room side point to moisture in the air settling on a cool surface. Dampness under the plastic means water is coming through the concrete itself. Bring that notebook to every site visit. A contractor who reads it and asks follow-up questions is giving you a diagnosis, not just a product.
Start outside the house
Water that ends up in a basement often began on the roof or in the yard. Walk the outside of your house during a hard rain and again on a day when snow is melting:
- Do the gutters overflow, sag between hangers, or drip at the seams?
- Does each downspout carry water several feet away from the wall, onto ground that keeps it moving?
- Does the soil next to the foundation slope away from the house, or has it settled into a dip that holds water?
- Are window wells full of leaves or standing water, and is there a drain at the bottom?
- Do a driveway, patio or stoop pitch back toward the wall?
Fixing these is ordinary work: clean and re-hang gutters, add downspout extensions, rebuild the slope with compacted soil, and keep mulch and planting beds from piling up against the siding. Snow shoveled off a walk and stacked against the foundation melts right where you least want it, so pile it out in the yard instead. Ask any waterproofing company you meet whether it looked at the outside before recommending work inside.
What a crack can and cannot tell you
Poured concrete shrinks as it cures, so thin vertical cracks in a basement wall are common and are often sealable from the inside with an injected product. Watch for signs of something more serious: a crack that is wider at one end than the other, a stair-step crack through block, one side of a crack sitting out past the other, or a wall that bows inward. Those point to movement, and a structural engineer should see the wall before anyone covers it with a membrane or panel. Pencil a mark at each end of a crack and date it, then check it each season to see whether it has grown.
Inside systems, in plain terms
When outside fixes are done and water still comes in, interior work is the next thing to weigh:
- Perimeter drain. The crew cuts a channel along the floor edge, lays perforated pipe in gravel, and patches the concrete. Water that reaches the wall is led to a sump.
- Sump and pump. A basin set below the floor collects that water and a pump lifts it out. Ask about the pump's capacity, the check valve, a sealed lid, and whether a battery backup is included.
- Wall membranes or dimple board. These guide water down the wall into the drain rather than stopping it at the surface.
- Exterior excavation. Digging to the footing to apply a membrane and drain on the outside. It is the largest job on this list and sometimes the right one.
Where the discharge goes
Every sump needs somewhere to send its water. Ask where the discharge line will end, how far from the house, whether it will stay clear of your neighbor's lot, and how the outlet is kept from freezing shut in winter. Also ask whether the city has any rules about connecting a sump line to a storm or sanitary sewer.
Paperwork questions
Ask each company what state license, if any, covers this work, and what the number is. Ask which city permits the job needs and who pulls them. Get proof of liability coverage and workers' compensation in writing, and call your insurer if you are unsure what your homeowner's policy covers for basement water.
Lining up proposals
When the written proposals arrive, set them next to one another and look for:
- the cause each company named, and the evidence it used;
- outside drainage work recommended before anything inside;
- feet of interior drain, the sump basin, pump model and backup;
- the discharge route and outlet;
- crack repairs, counted one by one, and any referral to an engineer;
- dehumidification if condensation turned up;
- the warranty, what it excludes, and whether it transfers to a buyer.