Off-grid site report
Medina County, TX
29.3454, -99.1277 · 876 ft elevationRead this before you act on anything below. This is my researched starting point for Medina 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 rulesMedina County, TX
Zoning & raw-land occupancy
Varies locallyMedina County has no countywide use-zoning ordinance for unincorporated land, per the Commissioners Court, but it does regulate platting/subdivision, and land near city limits can fall under that city's extraterritorial jurisdiction. A claim that the county doesn't regulate land use at all could not be confirmed officially. source
Dwellings, tiny homes & RVs
Unclear - verifyNo official Medina County page was found addressing tiny homes, RVs, or minimum dwelling size; the state default of limited county authority likely applies outside city limits. Cities like Hondo or Castroville may have their own rules, so check with city hall.
Building permits & codes
Varies locallyThe county's own permit guidance lists OSSF and driveway/utility permits as required, but no general residential building-code permit is mentioned on that page. Confirm with the county directly whether a building permit applies to your project. source
Septic & composting toilets
Generally allowedMedina County Environmental Health administers septic (OSSF) permitting under TCEQ authorization, requiring a licensed design and 911 address, with extra Edwards Aquifer standards in parts of the county. Aerobic systems need a maintenance agreement and a notarized affidavit filed at the courthouse. source
Greywater reuse
Unclear - verifyNo standalone Medina County or TCEQ greywater page was found; it appears to be handled within general OSSF design rules rather than as its own permit category.
Rainwater harvesting
Generally allowedNo Medina County ordinance restricting rainwater harvesting was found, and Texas generally encourages it at the state level; the Edwards Aquifer Authority has jurisdiction here but no found rule against catchment.
Private wells & water rights
Varies locallyThe Medina County Groundwater Conservation District requires a well construction application and payment before drilling, plus registration even for exempt domestic wells, and wells over the Edwards Aquifer need separate registration with the Edwards Aquifer Authority. source
Living disconnected from utilities
Unclear - verifyNo official Medina County ordinance requiring connection to electric, water, or sewer was found for unincorporated land; incorporated cities like Hondo or Castroville may set their own connection rules.
Sun30-year normals
- Peak-sun hours, annual average
- 5.5 hrs/day
- Worst month (sizes an off-grid array)
- 4.2 hrs/day
- Yearly output per 1 kW of panels
- 1,531 kWh
JFMAMJJASOND
Weather1991-2020
- Precipitation
- 30 in/yr
- Snowfall
- 0 in/yr
- Heating degree days
- 1,482 (mild)
How far help isstraight-line
- Hospital
Medina Community Hospital - 0.8 mi
- Fire station
Castroville Volunteer Fire Company - 14.9 mi
- Hardware store
South Texas Hardware - 15.0 mi
- Grocery
Walmart Supercenter - 0.1 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 78861).
Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt
Looking at a specific parcel in Medina 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.