Off-grid site report
Frio County, TX
28.8886, -99.0937 · 650 ft elevationRead this before you act on anything below. This is my researched starting point for Frio County, TX, not legal advice and not a guarantee. Rules change, and the deciding facts on any specific parcel (setbacks, perc results, overlay districts, deed restrictions, road frontage) live at the county or town office, not in any database. Before you buy land or build, confirm the current rules directly with the local zoning and health offices - the sources on this page tell you exactly who to call.
The local rulesFrio County, TX
Zoning & raw-land occupancy
Unclear - verifyNo countywide zoning ordinance was found on Frio County's official site; Texas counties generally lack zoning authority outside cities. The county does have Subdivision Regulations for platting land, administered by the County Engineer.
Dwellings, tiny homes & RVs
Unclear - verifyNo Frio County ordinance on minimum dwelling size, tiny homes, or RV occupancy was located. Texas law lets counties adopt such standards in unincorporated areas, but whether Frio County has done so is not confirmed; ask the county directly.
Building permits & codes
Varies locallyFrio County's Engineer's office handles subdivision-related development standards, and Texas counties in flood zones typically run floodplain development permits to stay in the NFIP, but a specific Frio County floodplain ordinance page was not found. Confirm with the County Engineer's office. source
Septic & composting toilets
Generally allowedFrio County runs its own OSSF (septic) permit program under state TCEQ rules (30 TAC 285). A state rule also sets a 75-foot septic setback from the Frio and other named rivers, and a 10+ acre exemption may apply under state rule if specific conditions are met. source
Greywater reuse
Unclear - verifyNo standalone Frio County or state greywater program was found; greywater is likely handled under the same OSSF/septic permitting framework. Confirm with the county's OSSF office.
Rainwater harvesting
Generally allowedNo Frio County restriction on rainwater harvesting was found; this follows the state's general encouragement of rainwater collection, with backflow-prevention rules applying only if connected to a public water system.
Private wells & water rights
RestrictedWells in Frio County fall under the Evergreen Underground Water Conservation District, a multi-county regional authority. State law also bars drilling within 100 feet of the Frio River and several other named rivers unless the well is an exempt domestic or livestock well on a tract over 10 acres. source
Living disconnected from utilities
Unclear - verifyNo Frio County ordinance was found requiring hookup to electric, water, or sewer utilities in unincorporated areas; this kind of requirement is typically a city matter (e.g., Pearsall or Dilley) rather than countywide. Not confirmed either way for unincorporated land.
Sun30-year normals
- Peak-sun hours, annual average
- 5.6 hrs/day
- Worst month (sizes an off-grid array)
- 4.4 hrs/day
- Yearly output per 1 kW of panels
- 1,541 kWh
JFMAMJJASOND
Weather1991-2020
- Precipitation
- 25 in/yr
- Snowfall
- 0 in/yr
- Heating degree days
- 1,664 (mild)
How far help isstraight-line
- Hospital
Frio Regional Hospital - 1.5 mi
- Fire station
Pearsall Fire Station - 0.1 mi
- Hardware store
Ace Hardware - 1.1 mi
- Grocery
H-E-B - 1.4 mi
From OpenStreetMap. Road miles will be longer, often much longer in hill country.
Plan this spot
These open with this location's real numbers already filled in (ZIP 78061).
Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt
Looking at a specific parcel in Frio County, TX?The rules above are the jurisdiction. The land check runs the parcel itself: flood zone, soils and septic suitability, wetlands, slope, access, climate, and these verdicts, from a parcel number or coordinates.
Check a parcel →Share or save this report:New report
Sources: US Census Bureau geocoder; NLR PVWatts v8 (solar); NOAA NCEI 1991-2020 climate normals (nearest station) or Open-Meteo (ZIP-centroid) for weather; Open-Elevation; OpenStreetMap contributors. Public data retrieved Aug 21, 2026; agencies update their layers on their own schedules. Planning data, not a survey or legal advice.
New here, or not sure where this fits? Start here walks through the whole thing in order.