Off-Grid Living in Clark County, Washington

I've been digging into what it actually takes to live off-grid in Clark County, Washington, and here's the honest picture based on official sources.

Zoning runs countywide under Title 40, the Unified Development Code, administered by Clark County Community Planning. Unlike some counties, there's no "unzoned" loophole here. Rural zones (Rural 5, 10, 20) are meant for rural residential living with small-scale farming or forestry as accessory uses. Resource zones like AG-20 and FR-40 carry large minimum lot sizes and tighter restrictions on dividing land. Which zone your parcel sits in changes what you can do, so this is a "call the county first" situation.

Dwellings, tiny homes, and RVs are workable but with real limits. Tiny houses on foundations generally follow the state building code baseline. I found secondary references to a county code section restricting detached accessory dwelling units in rural zones (attached only, with a hardship/caretaker exception process), but I could not confirm that specific code citation on an official Clark County or Municode page, so treat it as unverified until Community Development confirms it directly. Living in an RV as a permanent residence outside an approved park follows the state's baseline classification rules; no county-specific override turned up.

Building permits are mandatory and follow the International Residential Code with Washington state amendments and energy code requirements. Clark County's own residential permit packet requires plot plans showing septic lines, drainfields, and reserve drainfield areas.

Septic is closely regulated by Clark County Public Health under county code (Chapter 24.17), which requires any property not on municipal sewer to have an approved, functioning on-site system. Anyone servicing or installing a system must be certified by the county. A septic evaluation and release is required before certain building permits can even be issued.

Greywater reuse for subsurface irrigation is allowed under state rule (WAC 246-274), administered locally, but I couldn't confirm Clark County's specific implementation details or whether tier-one systems are locally allowed, so check with Public Health directly.

Rainwater harvesting for non-potable use doesn't require a water right permit from the state Department of Ecology if collected from an existing structure and used on-site. Using rainwater as your primary drinking water source for new construction needs county sign-off, and I didn't find a Clark County-specific policy confirming that process.

Wells rely on the state's exempt-well provisions, but Clark County requires a Water Availability Verification (WAVE) tied to septic release applications when a well serves a new dwelling. I found the WAVE process documented on the county's own septic form but couldn't locate the underlying ordinance number.

Full utility disconnection isn't explicitly addressed one way or the other. In practice, going off-grid means satisfying building code, septic compliance, and verified water supply, since no standalone prohibition was found.

Bottom line: Clark County lets you build off-grid, but nearly every piece routes through Community Planning, Community Development, or Public Health, and several specifics need a direct call to confirm.