Frio County, TX zoning map, flood zone and property lines by address
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Towns in Frio County: Pearsall, Dilley.
Flood zone by address
ParcelSheet reads FEMA's National Flood Hazard Layer at the lot: the zone, whether it is a high risk area where lenders ask for flood insurance, and the base flood elevation where FEMA lists one. FEMA has 11 FIRM panels covering Frio County, the newest effective April 2012; no coastal V zones are mapped in it.
The official panel and any Letter of Map Amendment are at FEMA's Map Service Center. An elevation certificate for a Frio house comes from a licensed surveyor and is often on file with the county or city building office.
Property lines
The parcel outline, parcel number and mapped size come from the Texas statewide parcel layer (StratMap Land Parcels, Texas Geographic Information Office, from each county appraisal district), so a Frio lot shows the same lines the appraisal district draws. Frio County covers about 725,440 acres of land and 542 acres of water.
Mapped lines are approximate. The Frio County appraisal district keeps the parcel record; every county's office is on the state's Comptroller county directory; a licensed surveyor sets the true corners.
Zoning
Texas counties cannot zone land. Under Texas Local Government Code chapter 211 only cities zone: in Frio County, Pearsall, Dilley each zone the land inside their limits. Land in Frio County outside city limits has no zoning district; deed restrictions, the county's subdivision rules (Local Government Code chapter 232), the septic permit and the floodplain rules still apply.
So check city limits first. ParcelSheet shows the use the appraisal district lists for the lot and the town it sits in; the city planning office has the district for land inside a city. What you can build outside city limits in Texas.
ADU and guest houses
Outside city limits in Frio County no county zoning limits a guest house or second home on a lot; deed restrictions and the septic permit, which must cover both homes, decide it. Inside a city, the city's zoning code sets the rule. ParcelSheet shows the mapped lot size and the ground's slope, the first two things the question turns on.
Septic and soil
ParcelSheet reads the USDA soil survey at the lot: the soil's name, its septic absorption rating and whether it is prime farmland. Frio County is soil survey area TX163, Frio County, Texas, last updated September 2026, on Web Soil Survey.
A new or changed septic system in Frio County needs a permit from the Frio County authorized agent of the TCEQ on-site sewage facility program, or the TCEQ region office where the county has none, which tests the soil on the lot itself.
Setbacks
Outside city limits in Frio County there are no county zoning setbacks; deed restrictions and the county's subdivision rules can still set distances. Inside a city such as Pearsall or Dilley, the city's zoning code sets the front, side and rear setbacks for the lot's district. ParcelSheet does not draw setback lines.
Hazards that apply
- Wetlands and wildfire. ParcelSheet shows the National Wetlands Inventory near a Frio lot and the Forest Service wildfire hazard rating at it.
Questions
Is my house in a flood zone in Frio County?
Type the address in the box above and ParcelSheet reads FEMA's flood zone at the lot's center. FEMA has 11 flood map panels covering Frio County, the newest effective April 2012. A lender or insurer uses the official FIRM panel; FEMA's Map Service Center has it.
How do I find property lines in Frio County?
Open the Texas map, type the address, and the parcel outline from the Frio County appraisal district shows on the map with its parcel number and mapped size. Mapped lines are approximate; only a licensed surveyor sets the true corners.
What is my property zoned in Frio County?
Zoning in Frio County is set only inside city limits, by each city (such as Pearsall, Dilley); Texas counties cannot zone, so land outside city limits has no zoning district. ParcelSheet shows the use code on the parcel record and names the municipality; the city planning office has the final word.
Can I build an ADU in Frio County?
Outside city limits in Frio County there is no county zoning, so no zoning rule limits a guest house; deed restrictions, the septic permit and the floodplain rules still apply. Inside a city, the city's zoning code under Texas Local Government Code chapter 211 sets the rule. ParcelSheet shows the lot size as mapped so you can see the room you have.
Do I need a septic permit in Frio County?
Yes. A new or changed septic system in Frio County needs a permit from the Frio County authorized agent of the TCEQ on-site sewage facility program, or the TCEQ region office where the county has none. ParcelSheet shows the USDA soil survey's septic rating at the lot, from survey area TX163 (Frio County, Texas).
What can I build on 5 acres in Frio County?
Texas counties cannot zone land, so check city limits first. If the 5 acres are inside a city (such as Pearsall, Dilley), that city's zoning sets what can go on them; outside city limits there is no county zoning, and deed restrictions, the county's subdivision and septic rules and the floodplain rules still apply. See the Frio County appraisal district.
What are the residential setbacks in Frio County (2026)?
Texas counties do not zone, so outside city limits there are no county zoning setbacks; deed restrictions and the county's subdivision rules can still set distances. Inside a city such as Pearsall or Dilley, the city's zoning code sets the front, side and rear setbacks for the lot's district. ParcelSheet does not draw setback lines. See the Frio County appraisal district.
Next to Frio County: Atascosa County, Dimmit County, La Salle County, Medina County, Zavala County.
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