Off-Grid Living in Oregon County, Missouri

I dug into Oregon County, Missouri for this brief, and I want to be upfront: I could not find an official county planning/zoning page, building department page, or county-hosted code on Municode, eCode360, American Legal, or a county GIS/government site. That absence is itself useful information, so let me walk through what I did and didn't confirm.

Zoning and raw land. Missouri's Chapter 64 RSMo requires voters in a second- or third-class county (which Oregon County is) to approve county-wide planning and zoning before it exists. Many rural Ozark counties have never taken that vote. I couldn't confirm one way or the other for Oregon County from an official source, so treat this as unclear at the county level, and remember the three incorporated towns, Alton, Thayer, and Koshkonong, could each have their own municipal zoning that would apply inside city limits.

Dwellings, tiny homes, RVs. Same story: no confirmed county ordinance. If the county hasn't adopted zoning or a residential code, this is likely unregulated outside city limits, but that's an inference, not a confirmed fact. Check with the county commission directly.

Building permits. Missouri has no mandatory statewide building code; each county decides whether to adopt something like the IRC. I found no evidence of an Oregon County building department or permit process, but that doesn't mean one doesn't exist, only that it isn't visible online. Call the courthouse.

Septic. This one is regulated, no ambiguity there. The authority comes from state law, RSMo 701.025 through 701.059 and the state's onsite wastewater treatment rules (19 CSR 20-3.060, 3.070, 3.080), administered by the Missouri Department of Health and Senior Services (DHSS). Locally, the Oregon County Health Department is the county's listed public health agency and is the most likely permitting contact, though I could not independently confirm on a county-branded page that they're the exact administering office for septic permits here. Composting toilets specifically aren't addressed separately that I could find.

Greywater. No state statute or Oregon County rule found. Ask the health department before installing anything.

Rainwater harvesting. Missouri state law protects a landowner's right to collect and use rainwater, and I found no Oregon County restriction on top of that.

Wells. Statewide Missouri Well Construction Rules (10 CSR 23), enforced by the Missouri Department of Natural Resources (DNR), govern well drilling and repair in every county including Oregon County. No separate county well ordinance turned up. The county health department does offer well-water testing as a service.

Off-grid utilities. Missouri protects a landowner's choice to rely on a private water system rather than hook up to public utilities, and I found no Oregon County ordinance mandating utility connection.

Bottom line: septic and wells are clearly state-regulated with a likely local health department touchpoint; zoning, dwellings, and building permits are genuinely uncertain here because I couldn't find county documentation, so a phone call to the courthouse is your best next step.