Buying land in Valley County, Idaho: what to check

Valley County covers 3,665 square miles of land and 68 of water in Idaho, with about 12,777 residents in 2024 (up 8.8% since 2020). The 2020 Census counted 100% of its land as rural and 32% of residents as living in urban areas. Farms operate 1.9% of the county's land. Below: how much of Valley County floods, what its soils allow, what farmland is worth and how often it's in drought, from free public data with every source linked.

Valley County at a glance

In the 100-year floodplain

under 1%

Below the state's county median (1.3%)

FEMA National Risk Index

Hydric (wetland-type) soils

2.3%

Above the state's county median (1.6%)

USDA NRCS Web Soil Survey (SSURGO)

Soils very limited for septic

100%

USDA NRCS Web Soil Survey (SSURGO)

Farm land value, 2022

$3,900/acre

Above the state's county median ($3,845)

USDA NASS, 2022 Census of Agriculture

Weeks in severe drought

9.9%

Share of weekly maps, 2021–2026

U.S. Drought Monitor county statistics

What to check before buying land in Valley County

Ordered by what Valley County's numbers point to. Every parcel differs, so treat this as where to look first.

  1. 1.Check slope where you'd build and where the driveway goes

    88% of Valley County's mapped soils have an average slope over 15% (USDA SSURGO).

    Steep ground means grading, retaining walls, longer driveways and erosion control. Compare the slope at the house site and along the access route, not just the parcel average.

    Guide: Terrain and slope

  2. 2.Budget for a perc test and maybe an engineered septic

    USDA rates 100% of Valley County's mapped soils "very limited" for conventional septic absorption fields and 0% "not limited".

    Without city sewer you need a septic permit from the county or state health department. Make the offer contingent on a passing soil or perc test; mound and aerobic systems can cost several times a conventional one.

    Guide: Perc tests and septic systems

  3. 3.Confirm legal road access and power

    The 2020 Census classified 100% of Valley County's land area as rural.

    Rural tracts are often sold without recorded access or a power line nearby. Get the title company to confirm a recorded easement or public road frontage, and ask the electric co-op what a line extension costs.

    Guide: Road access and landlocked land

  4. 4.Find out where the water comes from

    At least half of Valley County was in severe drought (D2) or worse in 9.9% of the 262 weekly U.S. Drought Monitor maps from 2021 to 2026. Idaho allocates water by permit or water right, so a well or pond isn't automatic.

    Ask whether the land has a public water connection, an existing well (and its log and yield), or neighbors' well depths from the state well database. For a new well, check permits and typical depth with the state agency first.

    Guide: Wells, public water and water rights

  5. 5.Check wildfire exposure and insurance

    FEMA rates Valley County's wildfire risk relatively moderate, and under 1% of the county's area is in the wildfire exposure zone the National Risk Index uses.

    Ask an insurer for a quote early; some carriers won't write new policies in high-hazard areas. Check access for fire trucks, nearby fire stations and the vegetation around the building site.

    Guide: Wildfire risk for rural land

  6. 6.Sanity-check the price per acre

    Farm real estate in Valley County averaged $3,900 an acre including buildings in the 2022 Census of Agriculture, and 2.4% of its mapped soils are prime or of statewide importance.

    Compare the asking price with recent sales of similar tracts, not the county average, which mixes cropland, pasture, timber and homesites. If an ag tax valuation applies, ask what the rollback taxes would be if you change the use.

    Guide: Land due diligence checklist

Flood zones, wetlands and water in Valley County

Area in the 1%-annual-chance (100-year) floodplain
under 1%, 6th lowest of 44 in Idaho FEMA National Risk Index
Mapped soils that flood occasionally or frequently
2.3% USDA NRCS Web Soil Survey (SSURGO)
Hydric soils (a federal wetland indicator)
2.3% USDA NRCS Web Soil Survey (SSURGO)
Poorly or very poorly drained soils
2.6% USDA NRCS Web Soil Survey (SSURGO)
Surface water (lakes, rivers, reservoirs)
68 sq mi Census 2024 Gazetteer Files
Drought on 2026-10-27
1.9% moderate or worse, 0% severe or worse U.S. Drought Monitor county statistics

The floodplain share is the area FEMA's National Risk Index counts as exposed to inland flooding, mostly mapped 100-year flood zones. It says how common flood-prone land is in Valley County, not whether a given parcel floods. For that, look up the zone at your exact point on the FEMA Flood Map Service Center or run the free check.

Soils and terrain

Prime only if drained, irrigated or protected
under 1% USDA NRCS Web Soil Survey (SSURGO)
Farmland of statewide importance
2.4% USDA NRCS Web Soil Survey (SSURGO)
Average slope over 15%
88% USDA NRCS Web Soil Survey (SSURGO)
Very limited for septic absorption fields
100% USDA NRCS Web Soil Survey (SSURGO)
Not limited for septic absorption fields
0% USDA NRCS Web Soil Survey (SSURGO)

Shares of Valley County's soil-surveyed land (about 2,355,512 acres, open water excluded), using each map unit's dominant condition in USDA's SSURGO soil survey. Soils change within a few hundred feet, so the soil at your building site is what matters.

Farms and land use

Share of the county's land in farms
1.9% USDA NASS, 2022 Census of Agriculture
Average farm size
319 acres (median 40) USDA NASS, 2022 Census of Agriculture
Average value of land and buildings
$3,900 per acre, 22nd highest of 44 in Idaho USDA NASS, 2022 Census of Agriculture
Pasture and rangeland
38,809 acres USDA NASS, 2022 Census of Agriculture
Woodland on farms
10,777 acres USDA NASS, 2022 Census of Agriculture
Irrigated land
15,245 acres USDA NASS, 2022 Census of Agriculture

Natural hazard ratings

FEMA's National Risk Index rates each hazard for Valley County relative to every other U.S. county. Overall risk: Relatively Low.

  • LandslideRelatively Moderate
  • WildfireRelatively Moderate
  • EarthquakeRelatively Low
  • River and inland floodingRelatively Low
  • LightningRelatively Low
  • Winter weatherRelatively Low
  • DroughtVery Low
  • HailVery Low
  • Heat waveVery Low
  • Strong windVery Low
  • TornadoVery Low

FEMA National Risk Index, December 2025

Questions about buying land in Valley County

How much of Valley County, ID is in a flood zone?

About under 1% of Valley County's area is in the 1%-annual-chance (100-year) floodplain used by FEMA's National Risk Index (December 2025), 6th lowest of 44 counties in Idaho. Whether a given parcel is in a flood zone depends on its exact location, so check the FEMA map at your pin.

How much does land cost per acre in Valley County?

The 2022 Census of Agriculture put the average value of farm land and buildings in Valley County at $3,900 an acre, 22nd highest of 44 counties in Idaho (the median Idaho county was $3,845). It's a self-reported average across farms, so small homesites and recreational tracts often sell for more per acre.

Will a septic system work on land in Valley County?

Often, but test first. USDA soil surveys rate 100% of Valley County's mapped soils very limited for conventional septic absorption fields, usually because of wetness, slow permeability, shallow rock or flooding. A perc or soil test on the parcel decides what system the health department will permit.

Is there good farmland in Valley County?

0% of Valley County's mapped soils are prime farmland, under 1% are prime only if drained, irrigated or protected from flooding, and 2.4% are farmland of statewide importance (USDA SSURGO). The 2022 Census of Agriculture counted 142 farms averaging 319 acres.

How often is Valley County in drought?

Since 2021, at least half of the county was in severe drought or worse in 9.9% of weekly U.S. Drought Monitor maps, and in extreme drought in 3.4%. On 2026-10-27, 1.9% of the county was in moderate drought or worse.

Can I check a specific property in Valley County?

Yes. Enter the address or drop a pin anywhere in Valley County on the free check. It shows which checks return data at that exact point, and the full report costs $29: flood zone, slope, soils, wetlands, roads, power lines, wildfire and more, each with its source. It is a screen of public maps, not a survey, title search or perc test.

Check the parcel, not just the county

County numbers tell you what to look for. The free check looks at your exact point in Valley County: flood zone, slope, soils, wetlands, roads, power and more. The full report is $29.

What these numbers can't tell you

  • County shares describe Valley County as a whole; a parcel can be entirely in or out of a flood zone, wetland or poor soil.
  • It doesn't look at the whole parcel, its boundaries, title, easements, zoning or permits.
  • It isn't a survey, appraisal, elevation certificate, soil or perc test, or Phase I environmental site assessment.
  • It can't see local distribution power lines, driveways, legal access, wells or mineral rights.
  • Maps lag behind the ground, and distances are straight-line, not driving distance.

Sources and vintages

Summarized per county by our build script on 2026-10-31. County figures cover the whole county; checks on the report are at your point.