Off-grid site report
Willacy County, TX
26.4527, -97.7816 · 39 ft elevationRead this before you act on anything below. This is my researched starting point for Willacy 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 rulesWillacy County, TX
Zoning & raw-land occupancy
Unclear - verifyNo countywide zoning ordinance was found on Willacy County's official site; Texas counties generally lack broad zoning power over unincorporated land, though the county's permits page mentions zoning processes and fees. Confirm with the Building Inspector's office. source
Dwellings, tiny homes & RVs
Unclear - verifyNo county rule on minimum dwelling size, tiny homes, or RV occupancy was found for existing tracts; the only related requirement is a groundwater adequacy test required when platting a new subdivision, per the county's plat checklist. source
Building permits & codes
RestrictedWillacy County requires building permits through its Building Inspector office, which also handles permit searches and zoning questions; the specific code edition adopted was not confirmed. source
Septic & composting toilets
Generally allowedSeptic (OSSF) systems are permitted under Texas TCEQ rules; Willacy County does not appear to be a TCEQ-authorized local permitting agent, so the TCEQ regional office (Region 15, Harlingen) is likely the permitting authority for individual systems, confirm by phone. source
Greywater reuse
Generally allowedWillacy County has no standalone greywater ordinance; its subdivision checklist simply requires compliance with the state's TCEQ greywater rules, so greywater reuse follows the state framework. source
Rainwater harvesting
Generally allowedNo Willacy County restriction on rainwater harvesting was found; the state's general allowance for domestic rainwater collection applies by default.
Private wells & water rights
Varies locallyNo Groundwater Conservation District covering Willacy County was confirmed, so the state's default rule of capture likely applies; new subdivisions must document well water quality and quantity per county and TCEQ/TWDB standards. source
Living disconnected from utilities
Unclear - verifyNo blanket utility-connection requirement was found for unincorporated Willacy County; the subdivision checklist allows individual wells and non-public water systems for new developments, but this wasn't confirmed for a single existing rural tract. source
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
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Weather1991-2020
- Precipitation
- 26 in/yr
- Snowfall
- 0 in/yr
- Heating degree days
- 753 (mild)
- Frost-free season
- Jan 31 to Dec 22
How far help isstraight-line
- Hospital
Valley Baptist Medical Center - 20.4 mi
- Fire station
Raymondville Fire Department - 2.0 mi
- Hardware store
The Visoria - 18.6 mi
- Grocery
H-E-B - 1.9 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 78580).
Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt
Looking at a specific parcel in Willacy 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.