Population from U.S. Census ACS 5-year tract estimates aggregated to county · flood from FEMA NFHL · contamination from EPA Superfund and state brownfields · generated 2026-10-07.
What the numbers mean for a buyer
Population is essentially flat (+11.4% since 2010). Physical constraints — access, water, soil suitability for septic — usually matter more to value here than growth-driven demand, because there is no rising tide to cover a bad parcel.
TerraIQs carries 24,942 scored parcels across Gillespie County's 1,058 square miles — about 24 per square mile. That profile is large working tracts rather than subdivided lots, so soil, water and legal access carry most of the value.
Flood risk in Gillespie County
Our current FEMA extract shows no mapped Special Flood Hazard Areas in Gillespie County. Read that precisely: it means detailed DFIRM flood mapping has not been published for this area, which is common in sparsely populated counties — it is not a finding that the land doesn't flood. For an unmapped county a report leans on terrain and slope analysis instead, and a local floodplain administrator is worth a call.
See how to check whether a Texas parcel is in a flood zone for what each zone letter obligates you to do.
Contamination and environmental records
No known contamination sites are recorded in Gillespie County in our source layers (EPA Superfund and state brownfields). That is a clean result for the datasets we carry, but these layers only cover reported sites — an unrecorded former dip vat, fuel tank or dump won't appear in any public layer.
Run a report on a Gillespie County parcel
Search by parcel ID, owner name or address. The report covers flood, pipelines, contamination, wells, soil, slope, zoning, infrastructure, protected areas, habitat and road access in one document. First report free.
What due diligence in Gillespie County involves
The county-level numbers above tell you what to expect; they don't settle any individual parcel. The checks that decide a deal — legal access, title exceptions, mineral severance, septic suitability, agricultural valuation rollback — are parcel-specific and partly document-based. Our Texas land due diligence checklist walks the full sequence in the order we'd run it, including which steps are free and which are worth paying for.
In Gillespie County specifically, note that pipeline crossings are common across Texas and are invisible from the road — pipeline easements restrict where you can build permanently.
Frequently asked
TerraIQs carries 24,942 scored parcels in Gillespie County. Statewide the dataset covers 14.3M+ parcels across all 254 counties; the scored subset is the rural-shard parcels, while urban and residential lots have full dossiers without a quality score.
Our current FEMA extract shows no mapped Special Flood Hazard Areas in Gillespie County, which means detailed DFIRM mapping has not been published there — not that the land doesn't flood. A parcel report falls back to terrain and slope analysis.
Flood zones, pipeline and utility proximity, contamination site distance, water well records, NRCS soil and septic suitability, slope and terrain, zoning where it exists, infrastructure, protected areas, critical habitat, road access with traffic counts, and population growth context — each with its source dataset version and retrieval date.