Off-grid site report
Washington County, TX
30.1407, -96.3955 · 351 ft elevationRead this before you act on anything below. This is my researched starting point for Washington 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 rulesWashington County, TX
Zoning & raw-land occupancy
Varies locallyWashington County has no general zoning authority over unincorporated land, that power comes from the state and the county hasn't been granted it broadly. However, the county does enforce Subdivision Regulations if you divide land, and ETJ areas near cities may involve shared review. source
Dwellings, tiny homes & RVs
Unclear - verifyNo official county page specifically addresses tiny homes, minimum dwelling size, or RV occupancy standards. Confirm directly with Washington County Engineering and Development Services. source
Building permits & codes
Varies locallyEngineering and Development Services administers permits tied to subdivision/platted development, but I could not confirm a specific adopted building code for unincorporated areas. Ask EDS directly. source
Septic & composting toilets
Generally allowedWashington County Environmental Health, under Engineering and Development Services, issues OSSF permits as an agent authorized by the state agency TCEQ, following state rules under 30 TAC Chapter 285. source
Greywater reuse
Unclear - verifyNo standalone county or TCEQ greywater rule was found; it appears to fall under the general OSSF septic framework. Confirm with Washington County Environmental Health before installing a separate system.
Rainwater harvesting
Generally allowedRainwater harvesting for domestic use is encouraged at the state level in Texas, and no Washington County restriction was found.
Private wells & water rights
Varies locallyIt's not confirmed whether Washington County lies within a groundwater conservation district; absent one, the state's default rule of capture applies. Well drillers must be TDLR-licensed statewide regardless. source
Living disconnected from utilities
Unclear - verifyNo state or Washington County law was found requiring utility hookups in unincorporated areas. Any such mandate would come from a city like Brenham if the property is within city limits or ETJ.
Sun30-year normals
- Peak-sun hours, annual average
- 5.3 hrs/day
- Worst month (sizes an off-grid array)
- 3.7 hrs/day
- Yearly output per 1 kW of panels
- 1,470 kWh
JFMAMJJASOND
Weather1991-2020
- Precipitation
- 45 in/yr
- Heating degree days
- 1,820 (mild)
- Frost-free season
- Mar 2 to Dec 1
How far help isstraight-line
- Hospital
Baylor Scott & White Medical Center - Brenham - 0.4 mi
- Fire station
City of Brenham Fire Department - 2.0 mi
- Hardware store
Lowe's - 0.2 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 77834).
Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt
Looking at a specific parcel in Washington 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.