GIS Map

Trempealeau County, Wisconsin GIS Map

This GIS map of Trempealeau County, Wisconsin (WI) shows the official Census county boundary (FIPS 55121), with federal layers you can switch on for FEMA flood zones, USGS elevation contours and hillshade, NLCD land cover, and school district lines.

Trempealeau County has a population of about 30,839 (U.S. Census Bureau, 2020-2024 ACS 5-year estimate) and a land area of 733 square miles. Use the inspect tool to read coordinates, elevation and the layers under any point.

State
Wisconsin (WI)
Population
30,839
Land area
733 sq mi
Density
42 / sq mi
Coordinates
44.3030, -91.3589
FIPS code
55121

Trempealeau County Demographics

Source: U.S. Census Bureau, American Community Survey 2020-2024 5-year estimates.

Population

30,839

Households

12,533

Median household income

$76,313

Median age

39.9 years

Median home value

$216,700

Median gross rent

$949/mo

Owner-occupied homes

74%

Bachelor's degree or higher

20.9%

Below poverty level

9.9%

Land area

733 sq mi

Population density

42 / sq mi

Trempealeau County Population Growth

Source: U.S. Census Bureau, 2010 Census and Population Estimates Program (Vintage 2024: April 2020 estimates base and July 1, 2024 estimate).

2010 Census

28,816

April 2020 (estimates base)

30,755

July 2024 estimate

30,801

Change 2010-2020

+6.7%

Change 2020-2024

+0.1%

Natural Hazard Risk in Trempealeau County

FEMA National Risk Index ratings for Trempealeau County, compared with all U.S. counties.

Overall risk

Relatively Low

Score 58.7 of 100

Expected annual loss

$20,088,131

Buildings, population & agriculture

Social vulnerability

Relatively Moderate

Susceptibility to hazard impacts

Community resilience

Relatively High

Ability to prepare & recover

Risk by Hazard

  • LandslideRelatively Moderate
  • HailRelatively Moderate
  • Cold WaveRelatively Moderate
  • LightningRelatively Moderate
  • Inland FloodingRelatively Low
  • Strong WindRelatively Moderate
  • Heat WaveRelatively Low
  • TornadoRelatively Low
  • Ice StormRelatively Low
  • Winter WeatherRelatively Low
  • DroughtRelatively Low
  • WildfireVery Low
  • EarthquakeVery Low

Source: FEMA National Risk Index (December 2025 release). County-level ratings are relative to other U.S. counties and are not a property-specific assessment.

Environmental Conditions in Trempealeau County, Wisconsin

Radon potential, monitored air quality and current drought status for Trempealeau County, Wisconsin, from the Environmental Protection Agency and the U.S. Drought Monitor.

Radon potential

Zone 2

moderate radon potential

EPA predicts an average indoor level between 2 and 4 pCi/L, so the EPA recommends testing, because elevated levels are still found in some homes here.

Drought status

Moderate drought in 6.2% of the county

Drought Severity and Coverage Index 33.4 of 500.

  • D0 Abnormally dry21%
  • D1 Moderate drought6.2%

Map of 13 October 2026.

Sources: EPA Map of Radon Zones (September 2025), EPA Air Quality Index (2024) and the U.S. Drought Monitor. A radon zone is a regional planning tool, not a prediction for any individual home — the EPA recommends testing every home regardless of zone. Air quality is shown only for counties that host an EPA monitor. Drought figures describe one weekly map, not a long-term climate average. Compare counties in Wisconsin.

GIS Data for Trempealeau County, WI

The Trempealeau County GIS map on this page loads live federal layers in your browser, so you can check flood zones, terrain, land cover and district boundaries anywhere in Trempealeau County without a separate GIS login. All of the Trempealeau GIS data below is drawn from public U.S. government sources.

Layers you can turn on

  • FEMA flood zones

    National Flood Hazard Layer — flood insurance rate map zones and floodways.

  • Elevation contours and hillshade

    USGS 3DEP terrain, so you can read slope and relief across the county.

  • Land cover

    NLCD land cover classes — forest, developed, wetland and water.

  • School districts

    Census TIGER unified and elementary school district boundaries.

  • ZIP code and county boundaries

    Census TIGER ZCTA and county boundary lines.

Map tools

  • Measure distance and area

    Draw a line or polygon to get length in miles or area in acres.

  • Sketch and annotate

    Add points, lines and shapes on top of the map.

  • Inspect any point

    Click the map to read coordinates, elevation and the layers under your cursor.

  • Download the map

    Save the current view as a PNG image.

Where the data comes from

County boundaries come from the U.S. Census Bureau TIGER/Line program, flood zones from FEMA's National Flood Hazard Layer, terrain from the USGS 3D Elevation Program, land cover from the Multi-Resolution Land Characteristics Consortium, and demographics from the American Community Survey.

Property records and tax maps in Trempealeau County

Most people who look up Trempealeau County GIS data are after parcel-level records: who owns a property, what it last sold for, and what it is assessed at. Those records are kept locally, not federally, so they are not part of this map. Trempealeau County property and tax map data lives with the county's own records office, and what that office is called varies by state — Texas counties run an appraisal district (usually searched as a “CAD”), Kentucky uses a Property Valuation Administrator (PVA), and most other states use a county assessor, auditor or tax office. Start with that office for a deed, a tax map number or a parcel boundary; use the map above for flood zones, elevation and land cover on the same land.

Trempealeau County FAQ

What state is Trempealeau County in?

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Trempealeau County is a county in Wisconsin (WI).

What is the population of Trempealeau County?

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Trempealeau County, Wisconsin has a population of about 30,839, according to the U.S. Census Bureau American Community Survey.

How big is Trempealeau County?

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Trempealeau County covers about 733 square miles of land, with a population density of roughly 42 people per square mile.

What is the FIPS code for Trempealeau County?

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The FIPS county code for Trempealeau County, Wisconsin is 55121. It is used to identify the county in federal datasets such as Census TIGER and FEMA flood maps.

What is the median household income in Trempealeau County?

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The median household income in Trempealeau County, Wisconsin is about $76,313 per year.

What is the radon zone for Trempealeau County?

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Trempealeau County is in EPA radon Zone 2, meaning the EPA predicts an average indoor radon level between 2 and 4 pCi/L. In this zone the EPA recommends testing, because elevated levels are still found in some homes here. The EPA is clear that a radon zone is a regional planning tool and not a prediction for any individual home.

Is Trempealeau County in a drought?

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As of the 13 October 2026 U.S. Drought Monitor map, moderate drought covers 6.2% of Trempealeau County, and the county's Drought Severity and Coverage Index is 33.4 out of 500.

What is Trempealeau GIS?

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Trempealeau GIS usually refers to the county's own parcel and zoning mapping system, which Trempealeau County publishes itself. This page is a separate, free viewer: it draws federal GIS layers — FEMA flood zones, USGS elevation, NLCD land cover and Census boundaries — over the Trempealeau County boundary, with no login required.

What GIS data is available for Trempealeau County?

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The Trempealeau County map loads federal GIS layers directly in your browser: FEMA National Flood Hazard Layer flood zones, USGS 3DEP elevation contours and hillshade, NLCD land cover, Census TIGER school district boundaries, and TIGER ZIP code and county boundary lines.

How do I check flood zones in Trempealeau County?

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Open the Trempealeau County map, turn on the FEMA flood zones layer, and zoom in. The National Flood Hazard Layer shows flood insurance rate map zones and floodways. Flood zones only draw once you are zoomed in far enough.

How do I find the coordinates or elevation of a spot in Trempealeau County?

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Use the inspect tool on the Trempealeau County map and click any point. It reads back the coordinates, elevation and the layers under your cursor. You can also measure distance and area by drawing a line or polygon.

Data sources for Trempealeau County, Wisconsin

Every figure on this page comes from a published government dataset. Each source is listed with its release date so you can check the number or cite it directly.

  • American Community Survey 5-year estimates

    U.S. Census Bureau · 2020-2024 · population, income, housing, education and poverty figures

  • Gazetteer Files

    U.S. Census Bureau · 2024 · place coordinates, land area and the county/place/ZIP crosswalk

  • TIGER/Line Shapefiles

    U.S. Census Bureau · 2024 · county, ZIP Code Tabulation Area and school district boundaries

  • National Flood Hazard Layer

    Federal Emergency Management Agency · current effective Flood Insurance Rate Maps · flood zones, floodways and base flood elevations

  • National Risk Index

    Federal Emergency Management Agency · v1.20, December 2025 · county natural hazard risk, expected annual loss, social vulnerability and resilience

  • 3D Elevation Program (3DEP)

    U.S. Geological Survey · current · elevation contours, shaded relief and point elevations

  • National Land Cover Database

    Multi-Resolution Land Characteristics Consortium · NLCD 2021 · land cover classes such as developed, forest, crop and water

  • Map of Radon Zones

    U.S. Environmental Protection Agency · September 2025 · the county radon zone (1, 2 or 3) and its predicted indoor radon potential

  • Air Quality Index annual summary by county

    U.S. Environmental Protection Agency · 2024 · median, 90th percentile and peak AQI, and days at unhealthy levels, for counties with an EPA monitor

  • U.S. Drought Monitor

    National Drought Mitigation Center, USDA and NOAA · weekly, current map · the share of county area in each drought category and the Drought Severity and Coverage Index

  • ArcGIS basemaps

    Esri · current · streets, satellite, topographic and dark gray basemap tiles

Citing this page

GIS Map, “Trempealeau County, Wisconsin GIS Map”, https://gismap.land/county/wisconsin/trempealeau. Figures from the datasets listed above.

How GIS Map sources and labels its data

Local notes for Trempealeau County, WI

Questions and local knowledge from people who know the area. Every note is read before it appears here.