GIS Map

Louisa County, Iowa GIS Map

This GIS map of Louisa County, Iowa (IA) shows the official Census county boundary (FIPS 19115), with federal layers you can switch on for FEMA flood zones, USGS elevation contours and hillshade, NLCD land cover, and school district lines.

Louisa County has a population of about 10,678 (U.S. Census Bureau, 2020-2024 ACS 5-year estimate) and a land area of 401.8 square miles. Use the inspect tool to read coordinates, elevation and the layers under any point.

State
Iowa (IA)
Population
10,678
Land area
401.8 sq mi
Density
27 / sq mi
Coordinates
41.2182, -91.2570
FIPS code
19115

Louisa County is not the only one — there is 1 other state with a county of the same name. Compare every Louisa County.

Louisa County Demographics

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

Population

10,678

Households

4,237

Median household income

$77,354

Median age

41.9 years

Median home value

$150,100

Median gross rent

$775/mo

Owner-occupied homes

80.3%

Bachelor's degree or higher

16.8%

Below poverty level

9.8%

Land area

401.8 sq mi

Population density

27 / sq mi

Louisa 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

11,387

April 2020 (estimates base)

10,839

July 2024 estimate

10,630

Change 2010-2020

-4.8%

Change 2020-2024

-1.9%

Natural Hazard Risk in Louisa County

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

Overall risk

Very Low

Score 17.5 of 100

Expected annual loss

$8,447,215

Buildings, population & agriculture

Social vulnerability

Very Low

Susceptibility to hazard impacts

Community resilience

Relatively Moderate

Ability to prepare & recover

Risk by Hazard

  • DroughtRelatively Moderate
  • Strong WindRelatively Moderate
  • HailRelatively Low
  • LandslideRelatively Low
  • Heat WaveRelatively Low
  • Ice StormRelatively Low
  • WildfireVery Low
  • TornadoRelatively Low
  • EarthquakeVery Low
  • LightningRelatively Low
  • Winter WeatherVery Low
  • Inland FloodingVery Low
  • Cold WaveVery Low
  • HurricaneVery 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 Louisa County, Iowa

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

Radon potential

Zone 1

highest radon potential

EPA predicts an average indoor level at or above 4 pCi/L, so the EPA recommends a radon test for every home in this zone, and a mitigation system for new construction.

Drought status

No drought

Drought Severity and Coverage Index 0 of 500.

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 Iowa.

GIS Data for Louisa County, IA

The Louisa 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 Louisa County without a separate GIS login. All of the Louisa 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 Louisa County

Most people who look up Louisa 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. Louisa 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.

Louisa County FAQ

What state is Louisa County in?

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Louisa County is a county in Iowa (IA).

What is the population of Louisa County?

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Louisa County, Iowa has a population of about 10,678, according to the U.S. Census Bureau American Community Survey.

How big is Louisa County?

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Louisa County covers about 401.8 square miles of land, with a population density of roughly 27 people per square mile.

What is the FIPS code for Louisa County?

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The FIPS county code for Louisa County, Iowa is 19115. 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 Louisa County?

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The median household income in Louisa County, Iowa is about $77,354 per year.

What is the radon zone for Louisa County?

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Louisa County is in EPA radon Zone 1, meaning the EPA predicts an average indoor radon level at or above 4 pCi/L. In this zone the EPA recommends a radon test for every home in this zone, and a mitigation system for new construction. The EPA is clear that a radon zone is a regional planning tool and not a prediction for any individual home.

Is Louisa County in a drought?

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As of the 13 October 2026 U.S. Drought Monitor map, no part of Louisa County is in drought.

What is Louisa GIS?

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Louisa GIS usually refers to the county's own parcel and zoning mapping system, which Louisa 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 Louisa County boundary, with no login required.

What GIS data is available for Louisa County?

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The Louisa 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 Louisa County?

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Open the Louisa 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 Louisa County?

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Use the inspect tool on the Louisa 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 Louisa County, Iowa

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, “Louisa County, Iowa GIS Map”, https://gismap.land/county/iowa/louisa. Figures from the datasets listed above.

How GIS Map sources and labels its data

Local notes for Louisa County, IA

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