Off-grid site report

Benton County, WA

46.2119, -119.1718 · 505 ft elevation

Read this before you act on anything below. This is my researched starting point for Benton County, WA, 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 rulesBenton County, WA

Zoning & raw-land occupancy

Varies locallyBenton County Planning Division administers countywide zoning, but permitted uses, lot sizes, and setbacks vary by district, so you must check the map for your specific parcel. source

Dwellings, tiny homes & RVs

Unclear - verifyA third-party source claims tiny homes are restricted to a manufactured-home-park zoning district and RVs only allowed temporary occupancy, but this isn't confirmed on an official Benton County page. Contact the Building Division directly. source

Building permits & codes

Generally allowedBenton County Building Division enforces the State Building Code Act and county code; the 2021 IBC/IRC and energy codes took effect March 2024, with added third-party plan review for commercial/tenant-improvement energy compliance since September 2024. source

Septic & composting toilets

Generally allowedBenton-Franklin Health District permits and inspects septic systems under WAC 246-272A and its own local standards; approval is generally needed before other permits are submitted. Composting toilets aren't separately addressed, so treat as unconfirmed beyond the state baseline. source

Greywater reuse

Unclear - verifyNo Benton County or health district page specifically addresses greywater reuse; the state WAC 246-274 baseline applies by default, administered locally by the Health District.

Rainwater harvesting

Unclear - verifyNo Benton County-specific rainwater harvesting rule was found; the state Department of Ecology's general policy on non-potable use is the presumed baseline.

Private wells & water rights

Varies locallyOutside the Yakima River Mitigation Area, standard state exempt-well rules apply, but within it Benton County's Rural Water Supply Program can limit new well usage based on a required mitigation package due to hydraulic ties to the Yakima River. source

Living disconnected from utilities

Unclear - verifyNo standalone county ordinance bans off-grid utility disconnection, but a legal dwelling still must clear Building Division permitting, Health District septic approval, and, in mitigation areas, water-supply requirements.

Open the full county page with sources →

Sun30-year normals

Peak-sun hours, annual average: 4.8 hrs/day
Worst month (sizes an off-grid array): 2.0 hrs/day
Yearly output per 1 kW of panels: 1,369 kWh

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Weather1991-2020

Precipitation: 8 in/yr
Snowfall: 1 in/yr
Heating degree days: 4,695 (moderate)
Frost-free season: Mar 30 to Oct 27

How far help isstraight-line

Hospital Trios Southridge Hospital: 2.5 mi
Fire station City of Kennewick Fire Station Number 2: 0.2 mi
Hardware store Harbor Freight Tools: 0.6 mi
Grocery WinCo Foods: 0.5 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 99336).

Size a solar system Heat loss & insulation Firewood per winter Rainwater harvest Garden size Panel tilt

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.